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AQA GCSE GEOGRAPHY
REVISION
Paper 1: Living with the physical environment
(1hr 30mins)
The Challenge of Natural Hazards – Natural hazards, Tectonic
hazards, Weather hazards and Climate change
The Living World – Ecosystems, Tropical Rainforests and Hot
deserts
NOT COLD ENVIRONMENTS
Physical Landscapes in the UK – UK landscapes, River
Landscapes and Coastal Landscapes
NOT GLACIAL LANDSCAPES
Unit 1: Challenges in the Physical Environment – Natural Hazards PLC
Spec Key Idea Theme Red Amber Green
1. Natural Hazards
Natural hazards pose
major risks to people and
property
What are natural hazards?
Name the different types of hazard
What is hazard risk?
2. Tectonic Hazards
Earthquakes and volcanic
eruptions are the result of
physical processes
Distribution of earthquakes and volcanoes – are
there any patterns?
Physical processes at plate margins –
constructive, destructive and conservative
The effects of, and
responses to, tectonic
hazards vary between
areas of contrasting levels
of wealth
The effects of earthquakes – Nepal and Italy
case studies
Responses to earthquakes – Nepal and Italy
case studies
Management can reduce
the effects of tectonic
hazards
Living with the risk from tectonic hazards –
include examples of places living with the risk
Reducing the risk from tectonic hazards –
monitoring, prediction, protection and planning
3. Weather Hazards
Global atmospheric
circulation helps to
determine patterns of
weather and climate
Global atmospheric circulation model – How
does it work? How does it affect the world’s
weather? Give examples.
Tropical storms
(hurricanes, cyclones,
typhoons) develop as a
result of particular physical
conditions
What is a tropical storm?
Where and how are tropical storms formed?
The structure and the features of tropical storms,
including frequency, distribution and intensity.
Tropical storms have
significant effects on
people and the
environment
Typhoon Haiyan – Primary and secondary
effects, Immediate and long-term responses.
Reducing the effects of tropical storms –
monitoring, protection, planning and prediction
The UK is affected by a
number of weather
hazards
Weather hazards in the UK – extreme weather –
thunderstorms, prolonged rainfall,
drought/extreme heat, heavy snow/extreme
cold and strong winds.
Extreme weather events in
the UK have impacts on
human activity
Beast from the East cause and effects – social,
economic and environmental
Beast from the East responses
Extreme weather in the UK – is it going to get
worse?
4. Climate Change
Climate change is the
result of natural and
human factors, and a
range of effects
What is the evidence for climate change?
What are the natural causes of climate
change?
What are the human causes of climate
change?
Managing climate
change involves both
mitigation (reducing
causes) and adaptation
(responding to change)
Managing the impacts of climate change -
mitigation
Managing the impacts of climate change -
adaptation
Definition of a natural hazard.
A natural hazard is a natural event which could cause death, injury or disruption to humans or
destroy property and possessions.
Types of natural hazard.
The Hazard can be …
Geological Hazards, these hazards can be split up in to two types; those that occur inside the earth
(tectonic/geophysical) processes e.g. earthquakes and volcanoes and those occurring on the
Earth’s surface (geomorphic) processes e.g. landslides and avalanches.
Hydrological Hazards, this is where there is either a harmful change in quality of earth's water or in
the distribution or movement of water e.g. (avalanches and floods),
Climatological Hazards, this is where there are changes in the earth’s climate e.g. extreme
temperatures (hot or cold), drought and wildfires.
Meteorological / Atmospheric Hazards, this is caused by extreme “one off” weather conditions e.g.
cyclones and storms/wave surges.
Biological Hazards, this is where living organisms are affected e.g. disease epidemics and forest fires
Factors affecting hazard risk.
Natural disasters frequently occur across the world, affecting both High Income Country (HIC) and
Low Income Country (LIC). However some populations are clearly more vulnerable than others.
Different communities and countries are more susceptible to the impact of these hazards especially
those in LICs.
Vulnerability
Poorer housing quality in LICs which causes higher death tolls, when the buildings collapse.
LICs have a poor economy so residents often have risky jobs in areas prone to natural events.
E.g. mining sulphur on volcanoes, farming on floodplains.
Increasing urban populations where natural events occur. The more people the higher the
death toll.
Capacity to cope
In HICs there are high quality buildings, using strong building materials and designs. E.g.
Earthquake proof buildings.
In HICs residents of areas prone to natural hazards have, better education, trained search
and rescue teams, action and evacuation plans.
In HICs more money is spent on technology to predict and protect the residents of the
country. E.g. In Japan, locals have texts warning them of approaching tsunamis.
Nature of the Natural Hazard
Duration: The length of time that a hazard lasts for. As a general rule the longer the hazard
the more severe it is likely to be.
Regularity: If hazards happen often and in quick succession e.g. a earthquake followed by
multiple aftershocks then the severity is likely to be greater.
Predictability: Some hazards are easier to predict than others. Generally speaking hazards
that hit with no warning are going to be more serious.
Magnitude: This is the strength of a hazard. Most hazards are measured on a scale. Generally
speaking, the stronger the hazard the more severe the hazard is.
Tectonic Hazards - Plate tectonics theory.
The Earth is made up of 4 layers. The crust, the mantle, the outer core and the inner core. The crust
and the upper mantle form the lithosphere. The lithosphere is broken into several major fragments
called tectonic plates, which either form the continents or the ocean floors.
Continental crust (lithosphere)
Land on top
Thick (30 – 100km)
Light in weight
Made of granite
Flexible
Will not subduct (Continental uplift.)
Older in age (3.8 billion years)
Oceanic crust (lithosphere)
Covered by ocean
Thin (5 – 10km)
Dense (heavy)
Made of basalt
Can be made to subduct. (Sunk and melted into the mantle.)
Younger in age (200 million years)
Global distribution of earthquakes and volcanic eruptions and their relationship to plate
margins.
Each plate has a different name. The
plates move in different directions; some
move towards each other, some
alongside each other and some away
from each other. Where plates meet it is
called a plate boundary/margin.
Convection currents occur when the core
heats the mantle. This creates a
convection current in the mantle. The
current drags the plates very slowly
moving them at the about the same
speed finger nails grow.
A ridge push occurs when the weight of an elevated ridge pushes an oceanic plate towards a
subduction zone.
A slab pull occurs as the weight of the subducting plate pulls the rest of the crust (lithosphere) into
the subduction zone.
Physical processes taking place at different types of plate
margin (constructive, destructive and conservative) that
lead to earthquakes and volcanic activity.
There are 3 different Plate Margins.
Constructive - When 2 plates move apart. Magma forces its way
to the surface and as it breaks through the overlying crust it
causes earthquakes. The magma is very hot and fluid. It will flow
a long way before cooling, resulting in a shield volcano.
E.g. North American and Eurasian Plates forming Iceland in the Atlantic Ocean.
Destructive - Where 2 plates move towards each other (this can
be either an oceanic plate or continental plate moving towards
each other or two continental plates which collide). Where an
oceanic and a continental plate meets the denser oceanic
plate subducts beneath the less dense continental plate. (It also
pulls the tip on the continental plate down too, forming a deep
ocean trench.) Friction between the plates causes strong
earthquakes. As the oceanic plate enters the mantle it starts to
melt, which creates more magma. The eruption are violent and
explosive due to the steam which is built up from the ocean water. Steep sided volcanoes called
composite volcanoes are formed here.
E.g. Pacific Oceanic Plate dipping under the South American Continental Plate.
Conservative - When 2 plates move alongside each other.
Friction between the plates builds up and can cause severe
earthquakes.
E.g. San Andreas Fault.
The effects of, and responses to, a tectonic hazard vary
between areas of contrasting levels of wealth.
Primary and secondary effects of a tectonic hazard - earthquakes.
Primary effects of an earthquake are the immediate impacts of the ground shaking e.g. buildings
and bridges collapsing, homes destroyed, people injured or killed by collapsed buildings or debris,
transport networks are damaged, power, water and communication networks cut off.
Secondary effects are what happen later on, often as a result of the primary effects e.g.
earthquakes can trigger landslides and tsunamis, leaking gas pipes can result in fires, people are
left homeless and could die from extreme weather conditions, shortage of clean water and poor
sanitation can lead to disease, destroyed transport networks results in difficulties getting emergency
vehicles in and trade, businesses destroyed which results in loss of income.
Immediate and long-term responses to a tectonic hazard.
Immediate responses are to stop loss of life e.g. rescue rapped people and treat injuries, recover
dead bodies to reduce spread of disease, put out fires, give shelter to homeless, provide water and
food, charities send aid workers.
Long term responses are where people are rehoused, repair buildings, transport and
communication networks, improve building regulations to prevent disaster occurring again.
Use named examples to show how the effects and responses to a tectonic hazard vary
between two areas of contrasting levels of wealth.
Reasons why people continue to live in areas at risk from a tectonic hazard.
People have deliberately chosen to risk all those hazards and live near them, even on the slopes of
active volcanoes that have erupted within living memory. They choose to live close to volcanoes
because they felt that the advantages outweighed the disadvantages. Most volcanoes are
perfectly safe for long periods in between eruptions, and those that do erupt more frequently are
usually thought of, by the people who live there, as being predictable.
Today, about 500 million people live on or close to volcanoes. We even have major cities close to
active volcanoes.
Farming
Volcanic rocks are rich in minerals, but when the rocks are fresh the minerals are not available to
plants. The rocks need thousands of years to become weathered and broken down before they
form rich soils. When they do become soils though, they form some of the richest ones on the planet.
(Volcanic soils are only found on less than 1% of the Earth’s surface). Ash from previous eruptions
provides very fertile soil. This is perfect for farmland. Today, the slopes of Vesuvius is intensively
cultivated and produces grapes, vegetables, orange and lemon trees, herbs, flowers and has
become a major tomato growing region.
Location Gorkha, Nepal –
LIC Case study
L’Aquila, Italy –
HIC Case Study
Date 28th April 2015 6th April 2009
Magnitude 7.8 6.3
Primary
Effects
8,841 deaths 308 deaths
16,000 injured 1,500 injured
one million made homeless 67,500 made homeless
Iconic historic buildings collapsed 15,000 buildings collapsed.
26 hospitals collapsed churches, medieval buildings, monuments
and museums
Secondary
Effects
Avalanche on Everest, swept through
base camp killing 19
Aftershocks caused landslides and rock fall
damage to housing and transport
The economy and employment in tourism
decreased considerably
Lack of housing in the area meant that
house prices and rents increased
Rice seeds kept in buildings which
collapsed during the earthquake, led to
food shortages.
Much of the city’s CBD (city centre) has
been cordoned off due to unsafe buildings
Short term
responses
Nepal could not cope requested
immediate international help
Within an hour the Italian Red Cross were
searching for survivors with 7 dog units.
Temporary shelters were set up by Red
Cross who provided tents for 225,000
people.
10,000 homeless people were put up in
hotels and 40,000 tents handed out
400,000 were unreachable by road or air.
The Sherpas were used to take supplies to
those stranded.
Water, hot meals, tents and blankets were
distributed. Mortgages, bills for Sky,
electricity, and gas were suspended.
Long term
responses
UN, EU and the World Bank reported that
23 areas needed to be rebuilt, including
homes, schools, roads, hospitals and
monuments
New settlements were built to
accommodate over 20,000 residents who
used to live in the damaged city centre.
$274 million had been promised for the
recovery of the country.
The EU granted $552.9 million.
Mount Everest was reopened for tourists
in August 2015, with alternative routes
planned
Students were exempt from paying
university fees for 3 years, had free public
transport and discount on equipment.
Geothermal Energy
Volcanoes can provide geothermal energy. Hot rocks beneath the volcano can provide a source
of cheap power for residents. Water is sent down into the volcanic rocks via a pipe. It returns to the
surface as steam. The steam turns a turbine, which is connected to a generator, which makes
electricity.
Countries such as Iceland make extensive use of geothermal power, with approximately two thirds
of Iceland's electricity coming from steam powered turbines, it is an excellent example of
renewable energy.
Tourism
Volcanoes attract more than 100 million visitors every year, for different reasons. As an example of
the wilder side of nature, there are few things that can beat seeing an erupting volcano. Even the
less active ones that are just puffing out steam and smoke are impressive sights and attract tourists
from around the world. Around the volcano may be warm bathing lakes, hot springs, bubbling mud
pools and steam vents. Tourism creates jobs in shops, restaurants, hotels and tourist centres /
national parks. Locals economies can profit from volcanism throughout the year, whereas skiing, for
example, has only a limited winter season.
Mining
Magma deep inside the earth contains a range of minerals. This means that minerals such as tin,
silver, gold, copper and even diamonds can be found in volcanic rocks. Most of the metallic
minerals mined around the world, particularly copper, gold, silver, lead and zinc are found in rocks
deep below extinct volcanoes. This makes the areas ideal for both large scale commercial mining
and smaller scale local activities by individuals and small groups of locals.
Families
Families have lived next to volcanoes for generations. They have a life there and do not want to
move away from their home. Many people do not take the threat particularly seriously or believe
they will have plenty warning to evacuate.
How monitoring, prediction, protection and planning can reduce the risks from a tectonic hazard.
There are four main management strategies for reducing the risk from tectonic hazards;
Monitoring (Using scientific equipment to detect warning signs of events.
Prediction – Using historical data, scientists can make predictions about when a tectonic hazard
may occur.
Protection – Designing buildings etc to withstand the tectonic hazards.
Planning – Train individuals as well as specialist teams on what to do in the event of a tectonic
hazard.
Weather Hazards - Global atmospheric circulation helps to determine patterns of
weather and climate.
General atmospheric circulation model: pressure belts and surface winds.
The atmosphere is the air above our heads. It contains gases, liquids and solids. E.g. water
vapour, carbon dioxide and oxygen. It is where our weather processes occur. A little like
the lithosphere where all the tectonic hazards occur. The atmosphere is where all the
weather /climate hazards occur.
Changes in climate is mainly due to latitude. At the equator
there is more insolation (amount of solar radiation received
in an area) than at the Polar Regions.
The air at the equator is heated strongly and has high
insolation (areas of high solar radiation). It becomes less
dense and rises towards the poles. This creates an area of
low pressure and causes poor weather e.g. cloud, rain and strong winds. It is known as a
depression.
At the poles there is low insolation (areas of low solar radiation) so the colder dense air
sinks towards the ground causing an area of high pressure. This causes fine dry and settled
weather known as anticyclones.
The Global Atmospheric Circulation Model
involves a number of circular air movements
called cells. These cells all join together to form
the overall circulation of the Earth’s atmosphere.
Convection cells are created where there are
differences in air temperature which lead to
areas of high and low air pressure.
There are three convection cells that operate;
Hadley cell – between the equator and the
tropics of cancer and Capricorn.
Ferrel cell – between the tropics and the polar fronts
Polar cell – between the poles and the polar fronts.
Not only is there the cells operating but there is also surface winds which affect the
weather and climate. The winds always travel from areas of high pressure to areas of low
pressure. These winds transfer heat and moisture from one place to another.
Global distribution of tropical storms (hurricanes, cyclones, typhoons).
A tropical storm is a huge storm that develops in the Tropics (Between the Tropic of
Cancer (30°N) and the Tropic of
Capricorn (30°S). They are an
intense low pressure weather
system. In different location in the
world tropical storms have different
names. In the USA and the
Caribbean they are called
hurricanes, in South-East Asia and
Australia they are called cyclones
and in Japan and the Philippine's
they are known as typhoons.
An understanding of the relationship between tropical storms and general atmospheric
circulation. Causes of tropical storms and the sequence of their formation and
development.
Tropical storms only develop over warm water when the sea temperature is 27°C or higher
and there is an atmospheric low, where air rises. When the warm, moist air rises due to the
condensation occurs and it releases huge amounts of energy, which makes these
powerful storm systems. All tropical storms move towards the west because of the easterly
winds near the equator. The Earth’s rotation (Coriolis Effect) deflects the paths of the
winds, which causes the storms to spin. The storm gets stronger due to energy from the
warm water, so wind speeds increase.
On average there are between 80-100
tropical storms a year.
Most tropical storms occur between 5 and
30°N/S of the Equator (depending on who you
ask!!) any further north or south the water isn’t
warm enough, however this is changing!!
They do not form exactly on the equator
though as there is not enough spin.
The majority of storms are in the northern hemisphere, especially in the Pacific. They
happen in late summer and autumn when the sea is at its highest temperature.
They lose strength as they move over land or cooler water as the energy from the
warm water is cut off, usually lasting7-14 days.
They only develop where there is good depth of warm water (70m).
They spin anticlockwise in the northern hemisphere, and clockwise in the southern
hemisphere
To record the intensity of the tropical storm the Saffir – Simpson Scale is used.
The sequence of their formation and development.
1. A strong upward movement of air draws water vapour up from the warm ocean
surface.
2. The evaporated air cools as it rises and condenses to form thunderstorm clouds.
3. As the air condenses it releases heat which powers the storm and draws up more
water from the ocean.
4. Several smaller thunderstorms join together to form a giant spinning storm. When the
wind speeds reach 120km/hr or 75 mph it is a tropical storm.
5. The storm develops an eye at its centre where air descends rapidly. The outer edge
of the eye, the eyewall is where there is the most intense weather conditions.
6. As the storm is carried across the ocean by the prevailing winds it continues to
gather strength.
7. On reaching land the storms energy is cut off. Friction with the land slows it down
and begins to weaken. If the storm reaches warm seas after crossing the land, it
may pick up strength again.
The structure and features of a tropical storm.
How climate change might affect the distribution, frequency and intensity of tropical
storms.
Climate change may affect tropical storms in 4 main ways…
Global temperatures are expected to rise as a result of climate change. This means
that most of the world’s oceans, sea surface temperatures (SST) could be above
27°C, so more places in the world may experience tropical storms. (Distribution)
Oceans will stay at 27°C or higher for more of the year, so the number of tropical
storms each year could increase. (Frequency)
Higher temperatures, will mean greater evaporation and higher wind speeds
making the tropical storms stronger, resulting in more destructive storms. (Intensity)
As temperatures increase, sea levels will rise due to thermal expansion. The impact
of rising sea levels will mean storm surges are expected to become higher.
(Intensity)
Data collection has improved through satellite monitoring, this may result in more
storms being recorded. As well as this the destruction may also seem to have
increased due to more people now living in expensive homes near the coast.
Primary and secondary effects of tropical storms.
Primary effects of tropical storms are:
The strong winds (upwards of 125 mph) can cause
widespread damage to buildings, infrastructure
(power lines, roads, and airports), trees and crops.
Storm surges, with the low air pressure sea levels are
very high, along with strong on-shore winds huge
waves are created causing extensive coastal flooding.
Heavy rainfall can cause widespread flooding.
Sometimes there are localised tornadoes.
Secondary effects of tropical storms are:
There may be landslides and mudslides as unstable slopes become saturated by
the heavy rain.
Polluted water supplies can cause diseases and further deaths.
People may be forced to make make-shift shelters due to the damage to their
homes.
Basic services affected as infrastructure awaits repair.
Immediate and long-term responses to tropical storms.
Immediate responses - When a tropical storm hits an area, the population and
government need to respond immediately e.g. putting the emergency services on
alert, evacuating the area, rescuing and treating victims of the storm.
In HICs detailed plans, forecasting and efficient communication means that damage
and loss of life will be kept to a minimum. The population will be alerted through the
media. The police and army will ensure that people evacuate from the area. However
in LICs infrastructure e.g. decent roads and poor communication make it difficult to
alert people to the dangers. Help from friendly governments will provide help.
Long term responses – When the danger is over rebuilding damaged housing and
infrastructure and improving protection systems e.g. levees. In HICs there is often less
damage and where there is damage governments respond quickly to make sure
bridges and roads are repaired quickly. In LICs it may be months if not years before
things return to normal. Normally there are long term health concerns with increasing
incidence of diseases such as cholera, typhoid and malaria.
Use a named example of a tropical storm to show its effects and responses.
Super Typhoon Haiyan hit the Philippines in November 2013.
It was classed as a category 5 with winds of 170 mph and
waves 15 metres high. There were also storm surges (wall of
water) of 5 metres high.
Primary Effects Secondary Effects
Approx. 6300 people died most through
drowning by the storm surge. 30,000
fishing boats destroyed by the surge
14 million people affected, many left
homeless and 6 million lost their income.
Over 600,000 people displaced due to
90% of Tacloban city destroyed.
Looting and violence broke out in
Tacloban city.
Tacloban airport and port badly
damaged.
Aid efforts were disrupted doe to
damage to the airport and port.
400mm of rain fell causing widespread
flooding.
Flooding and landslides blocked roads
cutting off aid to many remote places.
Buildings, bridges and power lines were
destroyed.
Power supplies cut off for months,
hindering people’s lives and businesses.
Water supplies contaminated and crops
destroyed.
Shortages of water and food led to
outbreaks of disease.
Immediate responses
International aid agencies responded quickly
with food, water and temporary shelters.
The Philippines Red Cross delivered basic food
aid e.g. rice & canned food.
Over 1200 evacuation centres set up for the
homeless. UK sent shelter kits to provide
emergency shelter for a family.
The French, Belgian and Israeli set up field hospitals to help the injured.
Long-term responses
The UN donated financial aid, supplies and
medical support.
Rebuilding of the airport, ports, roads and
bridges.
“Cash for Work” schemes where locals were paid
money to clear debris.
Oxfam helped finance replacement of fishing
boats.
More cyclone shelters have been made away from coastal areas.
How monitoring, prediction, protection and planning can reduce the effects of tropical
storms.
Monitoring and prediction
Satellite monitoring agencies can identify
the formation of tropical storms and track
their paths and strength (using the Saffir-
Simpson scale). Meteorologists can also
use the monitoring to provide warnings
with the use of a tracking cone. However
these are not 100% as the storm can
change its path and intensity very
quickly. The cone becomes larger with
time as the uncertainty of the storm increases.
Protection
In coastal areas buildings are often windproof and
storm proof, with reinforced windows, doors ad roofs.
In LICs there are often storm shelters designed for the
survival of whole villages. In some locations the
buildings are built on stilts, so the storm surge will pass
beneath. Sea walls also protect key properties along
the coast.
Planning
Tropical storm planning is mostly about raising awareness
both to individuals and communities. In the USA there is a
National Hurricane Preparedness Week, educating people
about the potential dangers. Governments produce posters,
leaflets ad information for the media and people are
encouraged to prepare disaster kits.
An overview of types of weather hazard experienced in the UK.
Weather hazards are extreme weather events. Even the UK experiences extreme weather, where
damage can be inflicted on communities. The main types of weather hazards are hydro-
meteorological hazards e.g. storms, flooding. Drought and extremes in cold weather.
Storm events
The UK is regularly hit by depressions which bring heavy rain to the
west coast of the UK. In October 2013 the St Jude storm had winds of
160km/hr killed 5 people, felled trees, toppled lorries, thousands lost
power and people were stranded at Gatwick airport as the planes
were grounded.
Flooding
Flooding often occurs due to depressions bringing persistent heavy
rainfall and strong waves. Storm surges can occur when strong winds
funnel coastal water into the mouth of a river e.g. In 1953 a storm
surge hit the Thames estuary killing 300 people. Flash flooding after
heavy rainfall can cause huge problems e.g. the village of Boscastle
in Cornwall was overwhelmed in 2004. After a period of heavy steady
rainfall the ground can become saturated causing slow onset river
flooding e.g. in 2014 the River Thames burst its banks. After intense rainfall water collects in valleys
causing surface water flooding e.g. in June 2007 thousands of homes flooded causing £3 billion in
damage.
Drought
Drought is an extended period of low or absent rainfall. In the UK this
means 15 consecutive days with less than 0.2 mm of rain. The longest
drought in the UK occurred over an 18 month period in 1975 and
1976. Temperatures exceeded 32°C for 7 consecutive days. Drought
conditions have also been recorded in 2003 (This drought affected
large areas of Europe as well and accounted for 20,000 deaths
across the continent, there was also the highest ever recorded
temperature in the UK 38°C), 2006 and 2012.
Heavy snow and extreme cold
Unusually cold winters occurred in 2010-11 and 2014-15. This caused
frost which destroyed crops and killed livestock with temperatures
plummeting to -10°C, over 17,000 trains were cancelled in 2014
because of freezing conditions and flights were hindered
considerably.
An example of a recent extreme weather event in the UK to illustrate: causes social, economic
and environmental impacts, how management strategies can reduce risk.
Beast from the East meets Storm Emma February – March 2018
Causes
The Beast from the East was caused by an event that occurred in
January when there was sudden stratospheric warming. This
involved a huge rise in air temperature of around 50°C in an area
around 18 miles above the Earth in the North Pole. This sudden
stratospheric warming caused a weakening of the jet stream (which usually brings in the warmer
air) and allowed the cold air from western Russia to "flood" over Europe.
Social Impacts
10 killed across the country
Hundreds trapped in their cars on roads and motorways
Gas supplies were running low and thousands without power
UK issued with a gas deficit warning
NHS cancelled non urgent operations
Schools across the country were closed for up to 3 days.
Economic
Trains stranded on tracks overnight causing delays to many
businesses
Thousands of businesses without or reduced power causing loss of
earnings
Road closures meant workers and materials needed to operate
some factories were unable to get where they were required forcing
some businesses to shut.
Shops, leisure facilities, theatres, cinemas and restaurants were
severely impacted as people were told to stay indoors and not
travel.
Farmers lost crops and livestock during the freezing conditions
The cost to the UK economy was estimated at least £1bn a day
Environmental impacts
15-20cm of snow fell over 3 days. There were snow drifts of up to 7m in rural areas.
Temperatures dropped to -10°C with wind chill of -22°C
Wind speeds exceeding 70mph
Management strategies
Armed forces deployed to rescue drivers and drive NHS workers to work to help the sick
and poorly
Greggs delivery van driver handed out food to those trapped in their cars to avoid hunger
Community centres were opened for those who are homeless to avoid further deaths from
exposure to the extreme temperatures
Taxi firms provided help to the elderly by bringing shopping and medicines to those in need
Met Office issued Red Waring to stop people travelling
Snow ploughs gritters and tractors out to clear roads to help people travel again
Government asked businesses to reduce their gas usage so the country didn’t run out
allowing people to have their heating on for longer
Red Cross issued blankets to people stranded in Glasgow Airport.
Evidence that weather is becoming more extreme in the UK.
The Intergovernmental Panel on Climate Change (IPCC) has warned that temperatures will
increase during this century. This will result in more evaporation and more rainfall. Scientists believe
that the UK will experience higher amounts of rainfall. Since the 1980s extreme winter rainfall has
increased. (Record rainfall amounts for the Lake District fell in Nov 2009, December 2015 was the
wettest month ever recorded in the UK)
UK temperatures have increased by about 1°C since 1980. (UKs highest ever recorded
temperature in Kent 38.5°C in 2003).
Climate Change - Evidence for climate change from the beginning of the quaternary
period to the present day
A geological timescale has been devised by those who have studied the history of the Earth. The
timescale has both Periods (Longer periods of time) and Epochs (Shorter periods of time within the
Periods).
Evidence of Climate change
Before reliable data records proxy data (natural recorders) have had to be used such as
tree rings, fossil pollen, ice cores and ocean sediments to estimate what the climate was
like. However these are not as reliable as they only indicate climate
change rather than specific accurate temperatures.
Scientists drill into the ice sheets of Antarctica to get cores of ice.
Within the ice there are gases trapped. They can tell what the
temperature would have been each year from these gases. Records
go back to 800,000 years.
As a tree grows it forms a new ring each year. The thicker
rings show that the year was warmer and wetter. Tree rings
are a reliable source of climate change over the last
10,000 years.
Pollen found in the bottom of lakes and peat bogs can help determine what
species were around at a particular time. If scientists know what conditions
those plants live in then they can tell what the climatic conditions were like.
Evidence of recent Climate change
Glaciers throughout the world are shrinking and retreating.
The average global sea level has risen between 10-20 cm due to thermal
expansion. As ocean water warms it expands in volume.
Tree flowering and bird migration is advancing.
The 134 billion tonnes of ice has melted in Antarctica since 2002.
The period of time we are currently in has been named
the Quaternary period or Ice Age which stretches back
to 2.6 million years. During this Quaternary period there
has been a global drop in temperature and is often
referred to as an ice age as there is permanent ice
sheets in Greenland and Antarctica.
The Quaternary Period has been split into the Pleistocene
Epoch where there were cold glacial episodes lasting
100,000 years, where the thick ice would expand over
continents but then also retreat, when there were
warmer interglacial periods.
The second part of the Quaternary Period is the
Holocene Epoch, the time we live in now, where the
climate has begun to get a lot warmer.
Possible causes of climate change – natural (orbital changes, volcanic activity and solar
output)
Orbital change
Milankovitch a Serbian geophysicist and astronomer studied the Earth’s
orbit and came up with three theories. Scientists now believe the cycles
Milankovitch came up with which occur every 100,000 years coincides
closely with the glacial and interglacial periods.
The Earth’s orbit changes from being circular to being elliptical
and then back to circular. As the Earth orbits closer to the sun, the
warmer the climate becomes.
The Earth spins on an axis causing night and day. This tilt alters
between 21.5° and 24.5° every 41,000 years causing differences in
the climate.
The Earth is not a perfect sphere so as the Earth spins it wobbles.
Solar output
The solar output of the sun is measured by observing the sunspots on
the Suns surface. The sun spots are caused by magnetic activity in the
sun. The number of sun spots increases over an 11 year period. When
sunspots are at their maximum the Sun gives off more heat resulting in
solar flares. When sunspot activity is at its minimum the solar output is
reduced.
Volcanic Activity
When large ash clouds are thrown vertically into the atmosphere
millions of tonnes of sulphur dioxide is released into the atmosphere.
When Sulphur dioxide mixes with water vapour it becomes a volcanic
aerosol. This can reflect the sunlight away and reduce the heat
entering the Earth’s atmosphere.
The greenhouse effect is a naturally
occurring phenomenon that keeps the
Earth warm enough for life to exist. It is
thought that without the greenhouse effect
the Earth would be approximately 33°C
colder and therefore life would not exist
how we know it today.
Scientists believe that the greenhouse
effect has been increased through the
actions of people. This action releases
greenhouse gases which increase the layer of gases already surrounding the Earth. This
traps more heat and is causing the planet to become warmer. It is like adding an extra
blanket around the Earth.
Possible human causes of climate change use of fossil fuels, agriculture and deforestation
Fossil fuels – Burning fossil fuels releases carbon dioxide into the
atmosphere and accounts for about 50% of greenhouse gas
emissions. Fossil fuels are used in transportation, heating homes and
manufacturing industry. They are also burnt in power stations to
generate electricity. As the world’s population increases and
become wealthier, people demand more and more energy.
Agriculture – Agriculture accounts for about 20% of greenhouse gas
emissions. It also produces large volumes of methane through cattle
and rice paddy fields.
Deforestation – Deforestation is the clearing of forests on a huge
scale. If trees are removed then carbon dioxide is not absorbed
during the process of photosynthesis, Also to remove the trees slash
and burn is often used, where the trees are burnt. The carbon stored
in the trees is the released.
How Climate change effects the environment
Warmer temperatures are causing the glaciers to shrink and ice sheets
to melt.
Sea ice is shrinking leading to the loss of polar habitats.
Sea levels are rising due to thermal expansion meaning areas like the
Maldives will be flooded more regularly.
Coral reefs are suffering from bleaching due to increasing ocean
temperatures.
How Climate change effects people
More extreme weather e.g. heat and cold waves have led to
deaths of the vulnerable.
Where areas are at risk of flooding people will migrate to other
areas causing possible overcrowding in some areas.
Agriculture will be affected in some areas, farmers will be able
to grow a greater range of crops, whilst other areas will suffer
and not be able to grow as much e.g. maize yields have got
smaller.
If crop yields decrease there may be malnutrition, ill health
and possibly even death.
Managing climate change through mitigation (reducing the causes) e.g. alternative
energy (renewable), carbon capture, planting trees and international agreements.
Mitigation looks at the cause of the problem, so looks to see how to reduce and prevent
greenhouse gases which causes the climate change.
Renewable Energy Sources – Wind, solar, geothermal, wave,
tidal and biomass forms of energy are being developed and
used more frequently as world population grows and incomes
grow and with it an increased demand for electrical products.
In 2010 new investments in renewable energies reached a high
of US$211 billion. By 2020 the UK aims to produce 15% of its
energy from renewable energies.
Carbon Capture and Storage – Coal is the most polluting
fossil fuel and countries rely heavily on it to produce
energy e.g. 80% of China's energy, 70% of India and 50%
of the USAs energy come from coal. Carbon capture is a
process where 90% of the carbon produced is captured
and returned underground via an injection well.
Planting trees (afforestation) – Trees act like carbon sinks,
removing CO² from the atmosphere through the process of
photosynthesis. They also release moisture into the
atmosphere producing clouds, which reduces the incoming
radiation.
International Agreements
Climate change is a global issue and requires global solutions. Carbon emissions spread
across the world and affect everyone.
Kyoto Agreement 2005
Over 170 countries agreed to reduce carbon emissions by 2012.
Copenhagen Accord 2009
Pledge to give LICs financial support to lower their impacts on climate change.
Paris Agreement 2015
195 countries signed the first universal and legal global climate deal. Reach a balance
between sources and sinks of greenhouse gases, keep global temperatures increase
below 2°C.
Managing climate change through adaptation e.g. changing agricultural systems,
managing water supply, reducing risk from rising sea levels.
This looks at responding to the impacts of climate change and tries to make populations
less vulnerable to climate change. These strategies are more local than global.
Changing agriculture – Agriculture needs to become
more “climate smart”. In some areas where there is less
rainfall, irrigation systems may need to be introduced.
Drought resistant crops may also need to be developed
through biotechnology.
Managing water supply – Climate change is already
causing more frequent droughts and floods. Vulnerable
area in rural areas of LICs are going to be hit hardest. In Asia,
millions of people rely on the water from the melting glaciers
in the Himalayas, water security is threatened. Artificial
glaciers have been formed in India where water is collected
during the summer, is frozen in the winter and as it melts in
spring it provides water for the villagers.
Reducing the risk of coastal flooding - Since 1900 sea levels have risen by 20cm. By 2100
sea levels are expected to rise a further 26-82cm. This could flood important agricultural
land in countries like Bangladesh, India and Vietnam. As sea levels rise rates of coastal
erosion will increase. Fresh water supplies will become contaminated with sea water.
The Maldives are going to be severely
threatened with future sea level predictions.
Some believe the islands will be inhabitable by
2030. In response to this 3 metre sea walls have
been constructed around the capital using sand
bags, buildings are raised off the ground on stilts,
3m high artificial islands have been constructed.
The worst case scenario is that all the inhabitants
will need to relocate to Sri Lanka or India.
Natural Hazards
1) What is a natural hazard? ___________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
2) Give two factors affecting hazard risk. _______________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
Tectonic Plates
3a) Name the type of plate margin where two plates are moving towards each other.
_______________________________________________________________________________________
Draw a simple diagram of the plate margin in the box below
3b) Name the type of plate margin where two plates are moving sideways against each
other.
_______________________________________________________________________________________
Draw a simple diagram of the plate margin in the box below
3c) Name the type of plate margin where two plates are moving away from each other.
_______________________________________________________________________________________
Draw a simple diagram of the plate margin in the box below
4) Why do volcanoes form at destructive plate margins? (Remember to use the following
key words in your answer; convection currents, oceanic, continental, subduct, mantle,
pressure, friction, weakness, crust)
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
5) At which types of plate margins can earthquakes occur?
_______________________________________________________________________________________
_______________________________________________________________________________________
6) Why do earthquakes occur at plate margins?
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
Effects of Tectonic Hazards
7) Give two primary and two secondary effects of a volcanic eruption.
Primary________________________________________________________________________________
_______________________________________________________________________________________
Secondary ____________________________________________________________________________
_______________________________________________________________________________________
8a) Give an example of an earthquake in a HIC.
_______________________________________________________________________________________
8b) Describe two primary effects of the earthquake and two secondary effects of the
earthquake.
Primary________________________________________________________________________________
_______________________________________________________________________________________
Secondary ____________________________________________________________________________
_______________________________________________________________________________________
8c) Give two immediate responses to the earthquake
_______________________________________________________________________________________
_______________________________________________________________________________________
8d) Give two long term responses to the earthquake
_______________________________________________________________________________________
_______________________________________________________________________________________
9a) Give an example of an earthquake in a LIC.
_______________________________________________________________________________________
9b) Describe two primary effects of the earthquake and two secondary effects of the
earthquake.
Primary________________________________________________________________________________
_______________________________________________________________________________________
Secondary ____________________________________________________________________________
_______________________________________________________________________________________
9c) Give two immediate responses to the earthquake
_______________________________________________________________________________________
_______________________________________________________________________________________
9d) Give two long term responses to the earthquake
_______________________________________________________________________________________
_______________________________________________________________________________________
10) Explain why do people live in areas prone to tectonic hazards?
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
11) Describe how management can reduce the effects of tectonic hazards. (Include at
least one method from Monitoring, Prediction, Protection and Planning)
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
Global Atmospheric Circulation and Tropical Storms
12) Fill in the blank model of the Global Atmospheric Circulation Model with the following;
The cells; Ferrell, Hadley and Polar Cells, Low and high Pressure and the direction of the
surface winds.
13) Describe the distribution of tropical storms. (Give latitude lines and the name of the
zone)
_______________________________________________________________________________________
_______________________________________________________________________________________
14) Name 3 conditions which are required for a tropical storm to develop?
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
15) In what direction does a tropical storm move?
_______________________________________________________________________________________
16) Which way do tropical storms rotate in the northern hemisphere?
______________________________________________________________________________________
17) What can cause a tropical storm to lose strength?
_______________________________________________________________________________________
_______________________________________________________________________________________
18) Describe two characteristics of the eye of a tropical storm.
_______________________________________________________________________________________
_______________________________________________________________________________________
19) How might climate change affect tropical storms?
_______________________________________________________________________________________
_______________________________________________________________________________________
20) Using an example describe two primary and two secondary effects of tropical storms.
Primary________________________________________________________________________________
_______________________________________________________________________________________
Secondary ____________________________________________________________________________
_______________________________________________________________________________________
21) Using an example, describe the immediate and long-term responses to a tropical
storm.
22a) Give two immediate responses to the tropical storm
_______________________________________________________________________________________
_______________________________________________________________________________________
22b) Give two long term responses to the tropical storm
_______________________________________________________________________________________
_______________________________________________________________________________________
Extreme Weather in the UK
23) List four types of extreme weather that can be experienced in the UK.
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
24) Give two pieces of evidence for the weather becoming more extreme in the UK.
_______________________________________________________________________________________
_______________________________________________________________________________________
25a) Give an example of one extreme UK weather event and explain what caused it.
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
25b) Describe two social, economic and environmental impacts of the extreme weather
event.
Social impacts
_______________________________________________________________________________________
_______________________________________________________________________________________
Economic impacts
_______________________________________________________________________________________
_______________________________________________________________________________________
Environmental impacts
_______________________________________________________________________________________
_______________________________________________________________________________________
26) What is the Quaternary period?
_______________________________________________________________________________________
_______________________________________________________________________________________
27) Give four sources of evidence for climate change over the Quaternary period.
1. ________________________________________________________________________________
2. ________________________________________________________________________________
3. ________________________________________________________________________________
4. ________________________________________________________________________________
28) Describe and explain the three main natural factors that can cause climate change?
1. _________________________________________________________________________________
_________________________________________________________________________________
2. _________________________________________________________________________________
_________________________________________________________________________________
3. _________________________________________________________________________________
_________________________________________________________________________________
29) What is the greenhouse effect?
_______________________________________________________________________________________
_______________________________________________________________________________________
30) What is the enhanced greenhouse effect?
_______________________________________________________________________________________
_______________________________________________________________________________________
31) How can human activities increase the concentration of greenhouse gases in the
atmosphere? (Give 4 activities and explain how they cause greenhouse gases).
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
32) Describe three mitigation strategies in which to reduce climate change.
1. _________________________________________________________________________________
_________________________________________________________________________________
2. _________________________________________________________________________________
_________________________________________________________________________________
3. _________________________________________________________________________________
_________________________________________________________________________________
33) Why are international agreements on climate change so important?
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
34) Name two international agreements designed to help tackle climate change
_______________________________________________________________________________________
_______________________________________________________________________________________
35) Describe three adaptation strategies in which to reduce climate change.
1. _________________________________________________________________________________
_________________________________________________________________________________
2. _________________________________________________________________________________
_________________________________________________________________________________
3. _________________________________________________________________________________
_________________________________________________________________________________
Unit 1: Challenges in the Physical Environment
Section B: The Living World Personalised Learning Checklist
Spec Key Idea Theme Red Amber Green
1. Ecosystems
Ecosystems exist at a
range of scales and
involve the interaction
between living and
non-living components
Introducing a small-scale ecosystem – tropic
levels within an ecosystem, food chains and
food webs.
How does change affect ecosystems?
Natural changes and human activity.
Global ecosystems – distribution and
characteristics of eight global ecosystems.
2. Tropical Rainforests
Tropical rainforests
have distinctive
environmental
characteristics
Environmental characteristics of rainforests –
location, climate, soil, plant and animal
adaptations.
Deforestation has
economic and
environmental impacts
Causes of deforestation in Malaysia –
logging, mineral extraction, population
pressure, commercial farming and
subsistence farming.
Impacts of deforestation in Malaysia –
social, economic, and environmental.
Tropical rainforests
need to be managed
to be sustainable
Managing tropical rainforests.
Sustainable management of tropical
rainforests.
3. Hot Deserts
Hot desert ecosystems
have distinctive
environmental
characteristics
Environmental characteristics of hot deserts
– location, climate, soil, plant and animal
adaptations.
Development of hot
desert environments
creates opportunities
and challenges
Opportunities for development of hot
deserts – Mojave, USA.
Challenges of development in hot deserts –
Mojave, USA.
Areas on the fringe of
hot deserts are at risk of
desertification
Causes of desertification in hot deserts –
The Sahel Region.
Reducing desertification in the Sahel.
The Living World – Ecosystems - An example of a small scale UK ecosystem to illustrate the
concept of interrelationships within a natural system, an understanding of producers, consumers,
decomposers, food chain, food web and nutrient cycling.
An ecosystem is a community of plants, animals, soils and the climate. There are complex
relationships between these 4 components. Biotic components are the living parts of the ecosystem.
(Plants and animals.)Abiotic components are the non-living pars of the ecosystem. (Climate, soils,
water and light.)
Ecosystems can be small scale (e.g. a garden) or a global scale (e.g. a rainforest or desert). These
are called biomes.
Keyword Definition
Producers Producers convert energy from the environment (mainly sunlight) into glucose.
E.g. plants convert energy from the sun by photosynthesis.
Consumers Consumers get energy from the sugars produced by the producers.
Decomposers Decomposers break down plant and animal material and return the nutrients
to the soil. E.g. Bacteria and fungi.
Food Chain Shows the direct link between producers and consumers in the form of a
simple line.
Food Web Shows all the connections between producers and consumers in a rather more
complex way.
Nutrient
Cycling
Nutrients are foods that are used by plant and animals to grow. Decomposers
help recycle the nutrients making them available for the growth of plants and
animals.
A small scale UK ecosystem – Birkacre woodland
Animals found in the
woodland include
insects, birds, rabbits,
squirrels and foxes.
Plants include trees, wild
flowers, grasses and
mosses. They provide food
and shelter for animals.
Soils store water and contain
nutrients which plants can
use. Soils are home to
insects and decomposers.
Sunshine and rain are
needed for photosynthesis.
Wind is also important for
seed dispersal.
Micro-organisms e.g. fungi and
bacteria are decomposers.
They release nutrients back into
the ecosystem.
A woodland food chain A woodland food web
At each of the trophic levels the amount of biomass and energy is lost this is because:
Many parts of the plants are not eaten by animals e.g. the roots and carnivores do not eat
all their prey e.g. the bones. Also most of what the animal eats is also excreted.
Energy is lost at each level when animals are chasing their prey, and also through
respiration.
Decomposers are organisms which break down dead organic matter and animal excretions.
Decomposers like bacteria and fungi help return the nutrients to the soil in the form of an organic
substance called humus.
Nutrient Cycling
Plants and animals rely on nutrients in
food for their health and vitality.
Nutrients occur naturally in the
environment and are constantly
recycled. See below.
The balance between components. The
impact on the ecosystem of changing
one component.
Physical events can disturb ecosystems for example an extreme
weather event or climate change. In the years 1976-77 southern
England had a drought of 18 months that killed many trees. A
further 15 million trees were felled in the Great Storm of 1987. As
a result population numbers declined.
Sometimes ecosystems can be damaged permanently through
deforestation. The removal of the canopy resulted in the soil
beneath getting washed away making it impossible for the
ecosystem to recover.
An overview of the distribution and characteristics of large scale natural global ecosystems.
Tundra or cold desert.
These are found at the
Arctic Circle where the
Sun’s rays have little
strength. Temperatures
are below freezing for
most of the year. Only
tough grasses can
survive.
Coniferous Forests
Found at 60°north where
winter temperatures are
extremely cold due to a lack
of insolation. The trees have
adapted by having needs to
reduce moisture and heat loss
in the cold dark months
Deciduous Forests
These grow in places
of higher latitudes e.g.
the UK and Western
Europe, east coast of
Asia, North America
and New Zealand
where rain is plentiful.
Mediterranean
Drought resistant small
trees and evergreen
shrubs grow between
30° and 40° north and
south of the equator but
only on the west coast
of continents.
Tropical grasslands /
Savannah
Sandwiched between
the rainforest and the
desert. These areas
experience dry and wet
seasons. Think
Madagascar!
Hot deserts
Found close to the
Tropics of Cancer and
Capricorn. These are
areas of high pressure
where air sinks causing
calm dry conditions. E.g.
Sahara and Australia.
Tropical Rainforests
These lie along the equator in Asia,
Africa and South America. There is
high insolation here as the sun is
directly overhead. The warm moist air
rises here which leads to heavy
rainfall. These are perfect conditions
for plant growth and high biodiversity.
Tropical Rainforests - The physical characteristics of a tropical rainforest.
Location
Climate
Tropical rainforests occur close to the equator, the
climate is warm and wet. Annual temperatures
average around 26°C and show little variation from
day to day and month to month. Annual rainfall usually
exceeds 2500 mm.
Line = temperature
Bars = rainfall
Soil
The soils in the rainforest are mainly thin and poor. This is the opposite to what you would think as
there is such an abundance of vegetation. The nutrients come from nutrient cycling. The warm
humid conditions cause the litter to decompose very quickly. The rainfall washes away the litter
nutrients making the soils infertile.
The interdependence of climate, water, soils, plants, animals and people.
See nutrient cycle diagram
Biodiversity
There is a high level of biodiversity in the rainforest. There are two-thirds of the world’s plant species
found in the forests and half of the known animal species. This rich biodiversity is getting
threatened by human activity, the challenge is to use the rainforest in a sustainable way and not
threaten the biodiversity.
How plants and animals adapt to
the physical conditions.
A rapid cycling of nutrients
through the ecosystem.
The absorption of sunlight,
leading to photosynthesis.
The warm, humid climate
which is ideal for plant
growth.
The ability to adapt to
adapt as they compete
for sunlight and nutrients.
The water cycle
Water is constantly recycled every day. The leaves of the trees are waxy and have
drip tip leaves to allow the water to run off them. The leaves also follow the sunlight.
The canopy intercepts the heavy rainfall before it hits the ground. Some of the
water is evaporated back into the atmosphere. The canopy acts like an umbrella
to prevent too much hitting the ground causing soil erosion. The smooth bark allows
the water to flow down to the forest floor easily.
Most rainforest plants have shallow huge roots called buttress roots that take rainwater and
dissolved nutrients directly from the decomposing leaf litter.
Competition for sunlight
There is a definite structure to the rainforest with four distinct layers. In each layer they have
adapted to the physical conditions. The forest floor receives very little sunlight so plants have huge
leaves to try and intercept the sunlight. Other plants (epiphytes) attach themselves to the tall trees
to enable them to receive more sunlight.
How have animals learnt to compete for food
There is a great deal of competition for food. Some animals are specialised and live off a
particular plant. E.g. toucans have strong beaks to crack open the hard nuts. There are
relationships between plants and animals as they rely on them to spread seeds. The birds eat the
fruit and then they fly some distance before they excrete dispersing the seeds.
Some animals use camouflage to hide from their prey, other animals use bright colours to warn
predators to leave them alone.
A case study of a tropical rainforest to illustrate: Malaysia
Causes of deforestation – subsistence and
commercial farming, logging, road building,
mineral extraction, energy development,
settlement, population growth
Malaysia is a country in South East Asia. It is
made up of Peninsular Malaysia and Eastern
Malaysia, which is part of the island of Borneo.
Deforestation is the cutting down of trees, often
on a very large scale. The timber is a highly
valued export, but also the land beneath the
forest is in high demand.
The rate of deforestation in Malaysia is increasing faster than in any other tropical country in the
world. Between 2000 and 2013 Malaysia’s total forest loss was an area larger than Denmark!
Commercial farming
Malaysia is the largest exporter of palm oil in the world. During the 1970s
large areas of land were covered to palm oil plantations. Plantations were
given a 10 year tax incentive so increasing amounts of land has been
converted to oil palm plantations.
Logging
Malaysia became the world’s largest exporter of tropical wood in the
1980s. Clear felling where all trees are chopped down in an area was
common. This led to total destruction of forests.
Road building
Roads are being constructed to provide access to mining areas, new
settlements and energy projects. Logging companies require roads to be
constructed to bring in machinery and take timber away.
Mineral extraction
Mining (mainly tin) is common in Peninsular Malaysia. Drilling for oil and gas
has recently started on Borneo.
Energy Development
In 2011 the Bakun Dam started to produce electricity. The dam supplies
energy for industrialised Peninsular Malaysia. The dam’s reservoir flooded
over 700km² of forest and farmland.
Impacts of deforestation – economic development, soil erosion, contribution to climate change
Economic development
Deforestation in many parts of the world is driven by profit. However whilst deforestation may result
in short term economic gains it may lead to long term loses too.
Economic gains
Development of land for mining and farming and energy will provide jobs both directly and
indirectly.
Companies will pay taxes to the government which can be used to improve services e.g.
education and water and energy supplies.
Improved transport infrastructure opens up new areas for industrial development and
tourism.
HEP will provide cheap and plentiful energy.
Economic loses
Fires can cause pollution. They can be burnt out of control destroying valuable forest.
The number of tourists attracted by rainforests could decrease.
Global warming can occur as trees absorb CO² (carbon dioxide) and emit O². CO² is a
greenhouse gas which can lead to global warming. If the trees are burned they also emit
CO².
Gold mining can release mercury into the ground as it is used to separate the gold from the
rock. This causes pollution of water supplies.
Without the canopy, soil erosion can occur which results in the soil becoming even more
infertile preventing crops from growing. Deforestation and the removal of the tree roots
prevents the soil binding together,
Indigenous tribes can experience conflict with the different economic activities as they are
forced off their land.
Value of tropical rainforests to people and the environment.
Value to people
Native food crops e.g. cocoa, sugar, bananas or products such as rubber or chemicals
from the plants are used to make perfumes, soaps, polishes and chewing gum.
Wild meat and fish
Building materials (timber)
Energy from HEP
Water supplies
Medicines. Pharmaceutical companies are finding new ingredients to treat and cure
diseases. Currently over 120 prescriptions drugs come from plants. 25% of our cancer-
fighting drugs come from the rainforest.
Value to the environment
Air purification (The trees absorb the CO²)
Water and nutrient recycling as shown previously in the booklet.
Protection from soil erosion.
Wildlife habitats for the abundant number of creatures which live in the forest.
Strategies used to manage the rainforest sustainably – selective logging and replanting, conservation
and education, ecotourism and international agreements about the use of tropical hardwoods, debt
reduction
To protect the world’s tropical rainforests they need to be managed sustainably. There are two main
reasons for this a) to ensure that rainforests remain a lasting resource for future generations b) to allow
valuable rainforest resources to be used without causing long term damage to the environment.
Selective logging and replanting
Malaysia set up a Selective Management System in 1977.
1. Firstly they study the areas prior to felling any trees
2. Trees which are suitable for economic gain are marked. Arrows are
drawn on so that they are cut in a particular way to avoid
unnecessary damage to surrounding trees.
3. Only licence holders are allowed to fell the trees.
4. Afterwards felling a survey is carried out on the site to ensure no illegal logging has taken place.
5. Plan drawn up to restore the forest.
6. Replacement trees planted
7. After 30-40 years cycle begins again.
Conservation and Education
Rainforests can be protected by having areas turned into national parks or nature reserves this ensures
that no illegal activity can take place in them. The areas can be used for education, scientific
research and tourism.
Some large international companies want to protect the rainforests so that they can keep on
extracting raw materials from the rainforest for the products they are making so they help protect large
areas so that they are not destroyed.
Ecotourism
Ecotourism aims to introduce people to the natural world, to benefit
local communities and protect the environment for the future. Through
income generated by ecotourism local people and governments
benefit from retaining and protecting their rainforest trees. This is more
sustainable than cutting them down for short term profit.
International and National Strategies for managing tropical rainforests sustainably.
In order to protect the rainforests of the world and prevent them from being lost forever, action needs
to be taken on a global, national and local level.
Global Level
Inter government agreements on hardwood trees and endangered species.
The International Tropical Timber Agreement (2006) and The Forest Stewardship
Council (FSC) restricts the trade in hardwood trees. The very high prices paid for
tropical hardwoods like mahogany has encouraged a huge amount of illegal
felling. This illegal felling usually occurs in more remote areas of the forest away from forestry officials.
However in the 2006 agreement hardwood timber must be felled in sustainably managed forests. This is
monitored by having each log marked with a registration number. Without the number the trees
cannot be sold for money.
The CITES (Convention on International Trade in Endangered Species 1973) treaty blocks the illegal
trade in rare and endangered animals and plants. However it is very difficult to monitor illegal trade
and it is still worth millions of pounds.
Debt Reduction by HICs
Most of the countries with tropical rainforests are Newly Emerging Economies
(NEE) or Low Income Countries (LIC). They may also have large debts from
HICs in the form of loans to help with the development of their country.
Different schemes have been created such as “Debt-for-Nature Swaps” have been arranged. In 2010
the USA signed an agreement with Brazil to convert the £13.5 million debt into a fund to protect large
areas of tropical rainforest. These swaps are known as debt reduction schemes. This is where HICs
agree to wipe out the debts of LICs so there isn’t as much pressure to cut down the rainforest for
economic activities so as to pay back the debts owed.
Conservation and Education by NGOs
Non-Governmental Organisations (NGOs) such as WWF & World Land Trust are charities that rely on
volunteers and donations. NGOs are not just bothered about rainforests they will operate anywhere
there they think ecosystems are being severely threatened. The work the NGOs do is as follows:
• Promote conservation through education programmes in schools and colleges.
• Provide training for conservation workers.
• Provide practical help with sustainable schemes.
• Buy up threatened areas and create nature reserves.
The organisations believe it is essential that these people and organisations which are exploiting the
rainforest are made to understand the consequences of their actions.
National Level
National Governments
Many countries with tropical rainforests have set up national parks and reserves within the rainforest to
help protect their rainforests. This restricts the damaging activities that can take place in the area e.g.
tin mining or logging. However there are huge problems in this strategy; a) few governments want to
slow down their economic activity and have a nature reserve instead, b) some governments seem
unwilling to enforce and monitor laws aimed at protecting or conserving the rainforest as they have
more immediate problems, c) there is a lot of corruption in the countries for e.g. illegal loggers and
developers will pay bribes to officials to allow them to log illegally.
As a result HICs are now paying money in exchange for rainforest conservation; Norway has paid $1
billion into Brazils Amazon Fund to help pay for conservation in the rainforest.
Hot Deserts
The physical characteristics of a hot desert.
Location
Hot deserts are found between 15° and 30° north and south of the Equator, along the Tropic of Cancer
and the Tropic of Capricorn. Large areas of the Earth’s surface are covered by hot deserts including
the Australian, Thar, Arabian, Gobi, Kalahari ,SW USA e.g. Mojave desert in The USA / Mexico and the
largest of all the Sahara.
Climate
In this area the climate is hot and dry. The area is extremely arid with less than
250mm of rain fall annually. This is because air around the Tropics of Capricorn
and Cancer is dry. This is a zone of high air pressure where the air sinks. Air at the
equator rises and cools - condensation then forms rain. The air then moves north
and south until it gets to about 30° north and south of the equator, where it sinks.
This air is dry and no condensation can form, so there is no rain. This is known as
the Hadley Cell.
There is also a big variation in temperature between day and night – the diurnal ranges. This is the
difference between the lowest temperature at night and the highest temperature during the day.
Sometimes during the day, temperatures can reach 50°C, however by night they can drop to 0°C.
Soils
Desert soils tend to be sandy or stony with little organic matter due to the general lack of leafy
vegetation, making them mostly infertile. Soils are dry but can soak up water rapidly after rainfall.
Evaporation draws salts to the surface (salinization) often leaving a white powder on the surface.
In some areas, calcium is present in the soils which is important for plant growth as it has not been
leached away. Once irrigated the land can be very productive for agriculture.
Issues related to biodiversity.
Desert biodiversity is far lower than other global ecosystems due to the dry conditions, hot climatic
conditions. Plants that survive the dry conditions are called xerophytic.
How plants and animals adapt to the physical
conditions
Drought tolerant trees – Acacia trees have
developed short fat trunks that act as reservoirs for
water. They are fire resistant in the intense heat and
can spread up to 50m in search of water.
Cacti e.g. Saguaro and Prickly Pear are called
succulents they store water in their tissue. The cacti
spikes deter consumers and their spikes minimise
transpiration.
Flowering plants like the Yellow Daisy only germinate after heavy rains. The bright flowers help attract
insects for pollination to occur.
Lichen using their own acids. They grow on bare rock surfaces. They break down the rock chemically
to get nutrients.
Animal adaption
In the hottest desert regions few animals can cope with the harsh
environment apart from a scorpions and small reptiles. In areas with some
water supply levels of biodiversity increases meaning in more vegetation
which allows mammals like foxes and coyotes to survive along with
buzzards and hawks.
Desert foxes / coyotes along with hawks are usually the top carnivores.
Kangaroo rats do not need to drink water, they
get it from their food. They live in burrows during
the day to avoid the extreme heat. They do not
perspire and have highly efficient kidneys that produce little urine. Their back
legs are a lot longer to allow them to jump away from predators and kick
sand at them.
Desert foxes have thick fur on the soles of their feet, protecting them from the hot
ground. The light coloured fur reflects sunlight and keeps them cool. They have big
ears that help cool the fox down and very good eyesight to see in the dark.
The interdependence of climate, water, soils, plants, animals and people
The biotic and abiotic components of an ecosystem are interdependent. Within the food web animals
eating plants have gained nutrients from the soil and water. The vegetation helps to bind and stabilise
the soil/sand to prevent erosion and desertification. Increasing human use of the deserts especially the
fringes threatens the environment.
A case study of a hot desert to illustrate: development opportunities in hot desert environments: mineral
extraction, energy, farming, tourism and the challenges of developing hot desert environments:
extreme temperatures, water supply, and inaccessibility.
SW USA Desert
Despite the barren nature of the desert a lot of different economic activities occurs. There are the
huge tourist attractions of Las Vegas and Grand Canyon, farming, mining, residential complexes and
energy production. All these activities bring wealth to the USA, however due to the delicate nature of
the ecosystem, it has to be managed carefully and sustainably.
Development opportunity 1 - Farming
Despite the harsh desert climate, in Southern California there are lots of farms growing fruit (e.g. lemons
and grapes) and cotton for the neighbouring big cities e.g. Los Angeles. To have successful farms
there needs to be efficient irrigation.
Challenge of water supply 1
Irrigation of crops (supply of water to dry areas) is a big problem in the south
of the USA and uses a huge amount of water. This can be either by using
aquifers (large stores of water underneath the ground) which can be
brought to the surface or from the River Colorado. Nearly, 80 percent of the
River Colorado's flow goes to farming. Much of it to low-valued crops, such as
fruit, cotton and potatoes that require lots of water. To ensure farming can continue in years to come
and so the sparse water from the River Colorado is not wasted, direct watering to the roots is being
trialled to prevent transpiration instead of spraying.
Development opportunity 2 - Tourism in Las Vegas
Guaranteed dry weather and sunshine attracts huge numbers of tourists
each year to the west coast of the USA which has led to tourism becoming
the Western Deserts most important source of income. There are a number of
tourist’s attractions in the desert in Western USA such as Death Valley, Grand Canyon, Colorado
River, Hoover Dam, Las Vegas and Route 66. The entire economy of Las Vegas is built around
entertainment and attracts 37 million visitors a year. To cater for these tourists Las Vegas has a
number of hotels, many with fountains and pools outside them. One such hotel/casino is the
iconic Treasure Island Casino.
The challenge of inaccessibility 1 – Due to the low population density of the desert there is a lack
of surfaced roads. However accessibility has improved as cities in the desert have developed e.g.
Las Vegas has an airport which receives over 40 million people each year. Surfaced roads have
been laid along with railroads.
The Challenge of water supply 2
The huge hotels consume large quantities of water with their fountains and hotel rooms with their
toilets and showers. The basement of the Treasure Island casino in Las Vegas is home to a water
recycling plant that cleans 100,000 gallons of water from its rooms and restaurants every day and
reuses it for outdoor landscaping. The hotels also have low flush toilets and water efficient showers.
Economic Activity 3 – Mineral Extraction
The west of the USA has a huge quantity of minerals below the surface
of the ground and is one of the USA’s most important mining areas. In
the past gold and silver attracted early settlers to the area. Today
copper, lead, uranium and coal are more economically important. Bingham copper mine near
Salt Lake City is the largest open-pit mine in the world. The mine is 2½ miles across, and ¾ mile
deep. To extract the minerals and resources high powered hoses are used to remove the topsoil,
thus wasting thousands of gallons of water a year. A plan for uranium mining near the Grand
Canyon was halted due to a campaign from the indigenous people who were concerned about
the risk to wildlife and possible contamination of the water supply.
Economic Activity 4 – Energy
The strong insolation in the desert regions provides fantastic
opportunities for solar power. The Sonoran Solar Project in Arizona is a
new solar plant project which will eventually produce energy for
100,000 homes and requires 360 people to build it.
Hydroelectric Power (HEP) also supplies western communities with energy. Water leaving Lake
Mead over the Hoover Dam helps provide locals not only with energy but also employment too. In
the mid-1930s the Hoover Dam employed over 5000 people.
There are also large reserves of fossil fuels in the Western Desert. Since 1905 people have been
drilling for oil in Arizona. Today there are 25 working oil sites in the area.
Challenge of extreme heat / water supply
Residents in the hot desert have adapted their homes by having air
conditioning, small homes which are whitewashed to reflect the heat
and to keep the building cool. Some residents have opted for fake
grass in their gardens to avoid the water wastage required to keep
grass alive. They have also opted for xeroscaping where they use
stones and flags instead of grass for their gardens.
Causes of desertification – climate change, population growth,
removal of fuel wood, overgrazing, over-cultivation and soil
erosion.
On the borders of hot deserts there are the world’s semi-arid areas
also known as desert fringes. An example of a desert fringe is the
Sahel which is to the south of the Sahara.
In these desert fringes rainfall is slightly higher than in the desert areas so agriculture is possible.
However despite the higher rainfall the desert fringes are very fragile environments, especially due
to climate change and poor land management. As a result desert fringes are at constant risk of
desertification. (This is where the land slowly loses nutrients and becomes more desert like and
unable to support a variety of plant and animal life). This is a major problem in some locations, for
example The Sahel, as 50 million poor and vulnerable people live there. The main causes of this
desertification are…
An increasing population growth and
migration from other less fertile areas puts
more pressure on the semi desert areas as
more people try and grow food to support
themselves (over cultivation) and rear
grazing animals on (overgrazing). This takes
the nutrients out of the soil and results in the
soils becoming infertile and unable to
support life.
Climate data shows that the Sahel has had a
long term reduction in rainfall in recent
decades. Scientists are certain that global
temperatures will rise but they are unsure
about rainfall patterns and some believe that rainfall will in fact increase “greening” the
Sahel, or it may become drier destroying valuable crop land.
Strategies used to reduce the risk of desertification – water and soil management, tree planting
and use of appropriate technology.
The majority of the 50 million people who live in the Sahel region suffer from poverty. Niger is losing
250,000 hectares of farmland every year through desertification. Millet crops have failed resulting
in a loss of both food and also money. Women often have to walk as 25 km a day to fetch water
for their families to use.
A range of water and soil management measures can help preserve soil quality and water
supplies;
• Tree planting schemes to bind and protect the soil
• Planting grass on slopes to stabile the topsoil so it doesn’t get blown away
• Building small rock dams to trap rainwater in gullies
• Collecting rainwater on roofs by designing a flat roof with a surrounding lip
• Building terraces (flattened sections with a retaining wall) on slopes.
Tree planting
Tree roots help to stabilise the soil, and the decomposing leaf
litter adds valuable nutrients into the soil. The African Union
proposes to plant a wall of trees (Great Green Wall) across the
entire Sahel region. It will be decades until the trees reach
maturity but it offers hope for a sustainable future for the
communities who live there. The planting of the trees also
provides work for some of the desperately poor in the region. Finally it has brought political
cooperation in the area, which will hopefully reduce conflict and the need for refugee camps
which adds further pressures to the fragile environment.
Appropriate Technology
In the past the removal of trees has been one of the biggest contributors of desertification. People
have used wood as a cooking fuel for thousands of years and as population increases this has put
further pressure on the area. Recently however an alternative ay of cooking has been introduced
using appropriate technology called “efficient stoves”. The stoves can be made locally using
materials like clay and small amounts of wood and charcoal and some have also been designed
to generate enough electricity to charge a mobile phone! Also in the desert fringe areas solar
power is being introduced. As well as providing energy for cooking, money made from the solar
power could help tackle the problem of desertification in the desert fringe areas.
Ecosystems Revision Questions
Ecosystems
1) What is an ecosystem?
_______________________________________________________________________________________
_______________________________________________________________________________________
2) Give two biotic features of ecosystems.
_______________________________________________________________________________________
3) Give two abiotic features of ecosystems
______________________________________________________________________________________
4) What is a producer and give an example.
_______________________________________________________________________________________
5) Describe the role of decomposers in ecosystems.
_______________________________________________________________________________________
_______________________________________________________________________________________
6) What is transferred in a food chain from each trophic level?
_______________________________________________________________________________________
7) Why is some energy lost at each trophic level?
_______________________________________________________________________________________
_______________________________________________________________________________________
8) What is the difference between a food chain and a food web?
_______________________________________________________________________________________
_______________________________________________________________________________________
9) Which biome is found between 15° and 35° north and south of the equator?
_______________________________________________________________________________________
10) Which biome is found above 60° north of the equator?
_______________________________________________________________________________________
Tropical Rainforests
11) Describe the climate of tropical rainforests. (Include rainfall and temperature)
_______________________________________________________________________________________
_______________________________________________________________________________________
12) Give an example of an interdependent relationship in the tropical rainforest
ecosystem.
_______________________________________________________________________________________
_______________________________________________________________________________________
13) Describe and explain three ways that plants are adapted to living in tropical
rainforests.
1. _________________________________________________________________________________
_________________________________________________________________________________
2. _________________________________________________________________________________
_________________________________________________________________________________
3. _________________________________________________________________________________
_________________________________________________________________________________
14) What is biodiversity?
_______________________________________________________________________________________
_______________________________________________________________________________________
15) Describe and explain three ways that animals are adapted to living in tropical
rainforests.
1. _________________________________________________________________________________
_________________________________________________________________________________
2. _________________________________________________________________________________
_________________________________________________________________________________
3. _________________________________________________________________________________
_________________________________________________________________________________
16) Give four causes of deforestation in tropical rainforests.
1. _________________________________________________________________________________
2. _________________________________________________________________________________
3. _________________________________________________________________________________
4. _________________________________________________________________________________
17a) Give an example of a tropical rainforest you have studied.
________________________________________________________________________________
17b) Describe three causes of deforestation in the rainforest you have studied.
1. _________________________________________________________________________________
_________________________________________________________________________________
2. _________________________________________________________________________________
_________________________________________________________________________________
3. _________________________________________________________________________________
_________________________________________________________________________________
17c) Describe the environmental impacts of deforestation in that rainforest.
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
17d) Describe the economic impacts of deforestation in that rainforest.
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
18) Why is it important to protect tropical rainforests?
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
19) What is sustainable management?
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
20) What is selective logging? How does it help protect the tropical rainforest?
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
21) What is ecotourism? How does it help protect the tropical rainforests?
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
22) How do international hardwood agreements help in the sustainable management of
rainforests?
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
23) Explain how reducing debt can be used in the sustainable management of rainforests.
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
Hot Deserts
24) Describe the climate of hot deserts. (include rainfall and temperature)
_______________________________________________________________________________________
_______________________________________________________________________________________
25) Describe and explain three ways that plants are adapted to living in hot deserts.
1.__________________________________________________________________________________
____________________________________________________________________________________
2.__________________________________________________________________________________
____________________________________________________________________________________
3.__________________________________________________________________________________
____________________________________________________________________________________
26) Describe and explain three ways that animals are adapted to living in hot desert.
1. _________________________________________________________________________________
_________________________________________________________________________________
2. _________________________________________________________________________________
_________________________________________________________________________________
3. _________________________________________________________________________________
_________________________________________________________________________________
27) Describe two ways that people cope with the lack of water in hot deserts.
_______________________________________________________________________________________
_______________________________________________________________________________________
_______________________________________________________________________________________
28) Name four development opportunities available in the hot desert you have studied.
1. _________________________________________________________________________________
_________________________________________________________________________________
2. _________________________________________________________________________________
_________________________________________________________________________________
3. _________________________________________________________________________________
_________________________________________________________________________________
4. _________________________________________________________________________________
_________________________________________________________________________________
29) Describe how inaccessibility can make development challenging in hot desert
environments that you have studied.
_______________________________________________________________________________________
_______________________________________________________________________________________
30) Describe how extreme temperature can make development challenging in hot desert
environments that you have studied.
_______________________________________________________________________________________
_______________________________________________________________________________________
31) Describe how water supply can make development challenging in hot desert
environments that you have studied.
_______________________________________________________________________________________
_______________________________________________________________________________________
32) What is desertification?
_______________________________________________________________________________________
_______________________________________________________________________________________
33) How is climate change affecting desertification?
_______________________________________________________________________________________
_______________________________________________________________________________________
34) How is human activity affecting desertification?
_______________________________________________________________________________________
_______________________________________________________________________________________
35) Explain how tree planting can reduce the risk of desertification.
_______________________________________________________________________________________
_______________________________________________________________________________________
36) What is appropriate technology?
_______________________________________________________________________________________
_______________________________________________________________________________________
37) How can appropriate technology reduce the risk of desertification?
_______________________________________________________________________________________
_______________________________________________________________________________________
Spec Key Idea Theme Red Amber Green
1. UK Physical Landscapes
The UK has a range of
diverse landscapes
The UK’s relief and landscapes – what is relief?
Where are the main upland areas and the
main rivers in the UK?
2. Coastal landscapes in the UK
The coast is shaped by
a number of physical
processes
Waves types and their characteristics –
constructive and destructive.
Weathering and mass movement
Coastal erosion processes – hydraulic power,
abrasion, corrasion, solution and attrition.
Distinctive coastal
landforms are the
result of rock type,
structure and physical
processes
Coastal erosion landforms – wave cut platform,
headland and bays, cave, arch, stack and
stump.
Coastal deposition landforms – beaches, spits,
bars and sand dunes.
Coastal landforms at Swanage – location and
type of coastline
Coastal landforms feature’s at Swanage
Different
management
strategies can be used
to protect coastlines
from the effects of
physical processes
Managing coasts – hard engineering – groynes,
rock armour, gabions and seawall.
Managing coasts – soft engineering – beach
nourishment, dune regeneration and dune
fencing.
Managing coasts – managed retreat – costs
and benefits.
Coastal management at Mappleton
3. River landscapes in the UK
The shape of river
valleys changes as
rivers flow downstream
Changes in the rivers and their valleys
Changes in the rivers and their valleys – long
and cross profile.
Fluvial (River) Processes – processes of erosion
and transportation.
Distinctive fluvial (river)
landforms result from
different physical
processes
River erosion landforms – waterfalls, interlocking
spurs and gorges
River erosion and depositional landforms –
meanders and oxbow lakes
River landforms on the River Tees
Different
management
strategies can be used
to protect river
landscapes from the
effects of flooding
Factors increasing flood risk – human and
physical factors
Managing floods – hard engineering
Managing floods – soft engineering
Managing floods – Banbury Case Study
Physical landscapes in the UK
In this section, students are required to study UK physical landscapes and two from Coastal
landscapes in the UK, River landscapes in the UK and Glacial landscapes in the UK.
An overview of the location of major upland/lowland areas and river systems.
Coastal Landscapes - Wave types and characteristics.
Waves are formed from wind blowing over the sea, the friction causes ripples to form which
develop into waves. The distance the wind blows over the surface is called the fetch. The longer
the fetch the more powerful the waves.
Constructive Waves; build up beaches
as they deposit material with their
strong swash and weak backwash.
They are low in height and form often
hundreds of kilometres away from the
beach.
Destructive Waves; destroy the beach
as they have a weak swash and strong
backwash. They are high and steep in
height and closely spaced producing
a chaotic swirling mass of water. They
are formed from local storms,
Upland areas Lowland area
The Fens
River
systems
Coastal processes: Weathering processes – mechanical, chemical
Cliffs can collapse because of different types of weathering. This is the weakening or decay of
rocks. It is mostly caused by weather factors such as rainfall and changes in temperature.
Mechanical weathering – the
disintegration of rocks. Where this
happens piles of rock fragments
called scree can be found at the
base of the cliff. Freeze thaw
weathering (frost shattering) is an
example of mechanical weathering.
Salt weathering is also a type of mechanical weathering where the slat in the sea water gets into
a crack. The water evaporates and crystallises putting pressure on the surrounding rock and
weakening it.
Chemical Weathering – is caused by a chemical reaction when rain water hit rock and
decomposes it away. This can occur when carbonic acid in the rainwater reacts with calcium
carbonate in limestone to form calcium bicarbonate, which dissolves the rock away.
Mass movement – sliding, slumping and rock falls
Mass movement is the shifting of rocks and loose material down a slope e.g. cliff. It happens when
the force of gravity acting on it is greater than what is supporting it. Mass movement makes cliffs
retreat rapidly. In 1993 60 metres of cliff slipped onto the beach near Scarborough in North
Yorkshire.
Erosion – hydraulic power, abrasion and attrition
Marine erosion is the removal of material by waves. Erosion will be higher where the coastline is
exposed to large fetch, strong winds blow (crating destructive waves) and there is no beach to
act as a buffer between the sea and the cliffs.
Hydraulic action is the force of the destructive waves pounding the cliffs. This causes repeated
changes in air pressure and water is forced in and out of faults and cracks.
Abrasion (Corrasion) is when destructive waves hurl sand and shingle at a cliff. The result is the
scratching and scrapping of the rock surface is called abrasion.
Attrition is the grinding down of particles as they are carried by the sea.
Sliding: This is the downhill
movement of a large
amount of rock, soil and
mud.
Rockfalls: Slopes must be
extremely steep. They are a
result of a variety of cause’s
e.g. extreme weathering
such as freeze-thaw action
may loosen material.
Slumps: Usually found on weaker
rocks (Clay), that becomes
saturated and heavy. Human
activity increases pressure on
rocks too.
Transportation – longshore drift
Load is transported
material. Most of it
originates from river
deposits, from eroded
headlands and the sea
bed. The larger and
stronger the waves are
the more load the sea
can carry and transport.
Longshore drift
The load is transported along the coast by longshore drift. The direction is determined by the
prevailing wind. The swash travels up the beach in the direction of the swash but due to gravity
the backwash returns at right angles to the shore. The load is therefore transported in a zig-zag
manner. Longshore drift is required for spits and bars to form.
Deposition – why sediment is deposited in coastal areas.
Coastal deposition takes place in areas where the flow of the water slows down and the waves
lose their energy. This results in the sediment that has been carried getting deposited.
Causes of deposition
There is low energy, in sheltered bays where
constructive waves are present.
Where there is a large expanse of flat beach
so the swash spreads out over a large area.
Where engineering works like groynes trap
sand.
How geological structure and rock type influence coastal forms.
The different geology, rock types and
rock structure around the UK coastline
has led to a variety of different coastal
landforms. Rock structure looks at how
the rocks are aligned in relation to the
coastline e.g. concordant and
discordant.
Characteristics (what they are look like or are like) and formation of landforms resulting from
erosion – headlands and bays, cliffs and wave cut platforms, caves, arches and stacks.
Characteristic of a headland – A headland is a cliff that juts out into the sea. They are made up of
hard rock e.g. granite, chalk or limestone which are difficult to erode. They have a near vertical
cliff face and are surrounded by water on three sides. There are often stacks and stumps.
Characteristics of a bay – A bay is a crescent shape
indentation in the coastline found between two
headlands. It usually has a beach made up of sand
or shingle.
Formation of headlands and bays – Headlands and
Bays form at discordant coastlines where there are
bands of hard (often chalk and limestone) and soft
rock (e.g. sands and clay). The soft rock erodes a lot
quicker through the processes of hydraulic action
and abrasion. Once the headlands and bays form
the processes change, in the bays there is less
energy and deposition occurs whereas the exposed
headland becomes the target for erosion.
Durlston Headland and Swanage Bay in Dorset
Characteristic of cliffs – In Dorset the cliffs are 45 metres in height, with a near vertical bare rock
face. There are wave cut notches at the base or foot of the cliff and there are fallen rocks in some
places.
Characteristic of a wave cut platform – An area of
bedrock which is visible at the base of some cliffs
when there is low tide. The platforms gently slopes at
an angle and are pitted with rock pools whilst other
areas are smooth due to the process of abrasion.
Formation of a wave cut platform – Destructive
waves hit the base of the cliff and through the
processes of hydraulic action and abrasion they
erode the base to form a wave cut notch. As further
erosion occurs the cliff above is left unsupported
until the overhang can no longer defy gravity and
falls to the beach. This creates a steep cliff. Over
time the cliff retreats back and leaves behind the
former base of the cliff as a wave cut platform.
Characteristics of caves – Caves are found in headlands and may be
several metres in height at their entrance but taper back. There are
many caves found at Durlston Head in Dorset. Blow holes may appear
in the caves.
Characteristics of an arch – Arches are found in headlands, they often
have a wider base due to wave cut notches. The sea water can go right through the gap.
Characteristics of a stack – These are detached pillars of rock located off a headland. They are
made of hard rock and often several metres in height, with wave cut notches at the bottom.
See diagram for formation – remember you must mention destructive waves, hydraulic action and
abrasion when writing about any of the erosion landforms mentioned on this page!
Characteristics and formation of landforms resulting from deposition – beaches, sand dunes, spits
and bars.
Characteristics of a beach – A beach is a coastal deposition landform which lies between the
high and low tide levels. They are formed of sand, sand and shingle or pebbles, as well as mud
and silt.
Sandy beach
Gradient is almost flat
Dominant waves are constructive
Long distance
Sand dunes sometimes present at the back of the beach
Pebble beach
Gradient is steep
Dominant waves are destructive
Short distance
Pebbles increase in size towards the back of the beach
A beach is formed through deposition, where the waves lose energy and deposit the load they
are carrying. A beach profile shows the gradient from the back of the beach to the sea. On some
beaches berms will form, this is where in calmer weather the constructive waves deposit material
onto the beach. These berms can eroded away in the winter with the more destructive waves.
The material which is eroded away from the berm can sometimes be deposited offshore to create
an offshore bar.
Characteristics of a sand dune
Sand dunes form on the dry backshore of a sandy beach.
Formation of a sand dune. For a sand dune to form there needs to a be
A large flat beach
A large supply of sand
A large tidal range so the sand
can dry
An onshore wind to move the
sand from the beach inland
An obstacle for the dune to
form.
Formation of a sand dune
On the leeward side
(sheltered) there is a
steep slip slope.
On the windward
side there is a
gentle slope.
Characteristics of a spit - A spit is a
sand or shingle beach that is joined
to the land but projects into the
sea. They are narrow steep
beaches, often several kilometres
log with a curve at the end. In the
sheltered area behind the spit
there are often salt marshes.
Formation of a spit – For a spit to
form there needs to be longshore
drift occurring and a sudden
change in the coastline or at the
mouth of a river where there is a
sudden drop in the waves energy.
Characteristics of a bar – A bar is a
ridge of sand or shingle that
stretches from one side of a bay to
another, forming a lagoon behind
it.
Formation of a bar – A bar is
created by longshore drift
transporting sediment from one side
of a bay to another.
Offshore bars also form see beach
topography diagram and
explanation.
An example of a section of coastline in the UK to identify
its major landforms of erosion and deposition.
Swanage is a seaside town in Dorset on the south east
coast of England. The area has both impressive erosion
and deposition landforms due to the differing rock types
and structure. There are a number of bays and
headlands due to the discordant coastline.
The costs and benefits of the following management strategies: hard engineering – sea walls, rock
armour, gabions and groynes.
Coasts sometimes need to managed and protected from erosion and flooding. With rising sea
levels, coastal flooding is expected to worsen and coastal protection strategies will become more
expensive. Areas with high property values will be protected whilst other stretches of coastline will
be left undefended.
Hard engineering techniques are expensive artificial structures. They are effective but do not
blend in well with the natural environment.
Sea walls are concrete barriers usually placed at the top of the
beach. They are usually curved to reflect the wave back out to sea,
and impedes the oncoming wave reducing the erosive power.
Benefits (advantages) - They are very effective at stopping erosion
and flooding. If maintained they last for many years. Often have a
walkway or promenade, especially useful in tourist towns.
Costs (disadvantages) - They can look obtrusive and unnatural, they
sometimes restrict access to the beach. They are also very expensive
(£5000 metre) and have high maintenance costs.
Rock Armour are piles of large boulders dumped at the foot of the cliff.
The rocks force waves to break absorbing the energy and protecting
the cliffs.
Benefits – Relatively cheap and easy to maintain (£1000 – 3000 metres).
They can be constructed quickly in a matter of weeks.
Costs – The rocks are usually from other parts of the coastline or abroad
(Norway and Sweden) so can be costly to transport. The rocks can
stand out as they don’t fit with the local geology, some feel it looks ugly
and can trap driftwood and litter. It is difficult to access the beach.
Gabions are wire cages filled with rocks that can be built up to support
a cliff or provide a buffer against the sea.
Benefits – They are cheap to produce (£100 - 500 metre) and flexible.
Vegetation usually starts to grow over them making them blend into
their surroundings more.
Costs – They can look really unattractive and the cages only last 20-25
years but after 5-10 years they start to rust. Maintenance is required so
that people and animals don’t get cut on the broken steel mesh.
Groynes are timber or rock barriers built out to sea at right angles
to the coast. They trap sediment being moved by longshore drift
and make the beach larger. The wider the beach the better it is
as acting as a buffer to the destructive waves.
Benefits – They create wide beaches which are popular for
tourists. They are not too expensive (£50,000 - 150,000 each
placed at 200m apart) and can last up to 40 years.
Costs – The sand trapped starves the beach further along the
coast often leading to increased rates of erosion elsewhere.
Groynes look unnatural and can look unattractive, especially
older, decaying ones. The groynes impede walking along the
beach and can be dangerous as they create uneven beaches.
Soft engineering – beach nourishment and profiling, dune regeneration, managed retreat –
coastal realignment.
Soft engineering techniques are less intrusive and more environmentally friendly. They are
generally less expensive but often less effective as well.
Beach nourishment is where there is a replacement of the
sediment which has been lost. A wider beach helps absorb the
wave’s energy resulting in less erosion of the coastline. The
sediment is either taken from the sea bed or from areas down
drift where material has been transported by longshore drift.
Benefits – It looks natural and blends in with the environment,
the beach buffers the waves and allows protection of
expensive coastal properties and a wider beach will
encourage more tourists into the village/town.
Costs – Access to the beach is restricted for several weeks. Despite lower costs than hard
engineering techniques, it still costs e.g. £500,000 per 100 metres.
Beach reprofiling is the artificial re-shaping of a beach using
existing beach material. Sediment can be removed in the winter
months, bulldozers move the shingle back up the beach in order
to protect the cliffs.
Benefits – It is very cost effective, reprofiling costs approx. £30
million whereas repair costs could cost up to £125 million. The
beach looks more natural than those with hard engineering.
Costs – bulldozers restrict access to the beach. The beach is
steep and may look uninviting to tourists.
Sand dune regeneration is the artificial creation of new sand
dunes or restoring existing dunes, Sand dunes absorb the wave
energy and water, in this way they protect the land from the sea.
Benefits – Sand dunes are popular as picnic and walking areas.
Habitats are created for rare species e.g. sand lizards.
Costs – fencing round sand dunes whilst they establish may put
tourists off, walkways have to be bought to prevent trampling of
vegetation. Sand dunes are dynamic systems which are
constantly changing so there is no guarantee they are stable,
especially during storms.
Coastal realignment is where coastline is engineered into a new position, often using managed
retreat.
Managed retreat is a deliberate policy of allowing the sea to flood
or erode an area of relatively low land value. It is a more
sustainable method instead of spending large sums of money on
hard engineering techniques. People are moved out of the areas
and buildings are demolished.
Benefits – It is often cheaper to use managed retreat rather than
building hard engineering strategies and takes the pressure off
other areas. It also creates new habitats on the mudflats e.g.
Shellduck.
Costs – Relocation of people into new homes causes disruption and distress, destroying coastal
village communities. Large areas of agricultural land are lost and some habitats are destroyed.
An example of a coastal management scheme in the UK to show: the reasons for management
the management strategy and the resulting effects and conflicts.
Holderness is a 50km stretch of Yorkshire coastline. It is one of the fastest
eroding coastlines in Europe. Over the last 2000 years, 26 villages have
disappeared into the North Sea and the village of Mappleton is under threat
of being number 27.
The reasons for management – There is a need to protect this coastline as it is
made of soft boulder clay which is a very soft rock. This along with the highly
destructive wave and thin beach results in 7-10 metres of coastline being lost
to the sea each year.
There are a number of socio economic reasons why there is a need for
management; a number of farms have been lost, resulting in unemployment, the B1242 main
coastal road is under threat, properties and businesses in Mappleton are under threat, the gas
plant close to the coast is also under threat of closure which would cause huge unemployment in
the area.
Management strategies
In 1991 £2 million was spent on saving Mappleton. They shipped in granite from Norway for rock
armour and two rock groynes, to help reduce longshore drift and to build up the narrow beach.
Cliffs have been covered in vegetation to stabilise the boulder clay to avoid further slumping.
Effects
Many people’s homes and businesses were saved. It
has allowed the community to continue and stopped
the disruption and distress of moving house.
A number of cliff top businesses benefited from the
scheme as a caravan park and some shops were
saved.
The B1242 road was saved! In the long term this saved
lots of money as it would have cost much more to re-
route it.
Conflicts
There has been a massive increase in erosion rates south of
Mappleton due to the protection schemes. This has led to
farms and other businesses having to close further along
the coast.
Some people believe that too much money was spent in
Mappleton (£2 million) and that government money should
be used for more important things like schools and
hospitals.
Some people are not happy with the management
scheme at Mappleton on the grounds that it makes the
coastline look unnatural.
Due to the groynes, Spurn Head spit has had a smaller amount of sediment being
transported to it by longshore drift. Environmentalist are worried that habitats for rare birds
are being affected by this.
Coastal Landscapes in the UK
Weathering and Erosion
1) What is weathering?
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2) How does freeze-thaw weathering break up rock?
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3) What is carbonation weathering?
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4) Name three types of mass movement?
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5) Name three types of erosion caused by waves? Explain how they work.
4. _________________________________________________________________________________
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5. _________________________________________________________________________________
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6. _________________________________________________________________________________
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6) Give four characteristics of destructive waves.
1. _________________________________________________________________________________
2. _________________________________________________________________________________
3. _________________________________________________________________________________
4. _________________________________________________________________________________
7) How does a wave-cut platform form? Draw and label 4 diagrams to show the
formation.
8) Are headlands made of more or less resistant rock? _________________________________
9) Label the diagram below and then describe and explain how erosion can turn a crack
in a cliff into a cave.
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Transportation and Deposition
10) How does longshore drift transport sediment along a coast? Draw a diagram in the
box below.
11) What are the other four ways in which the sea transports material?
1.___________________________ 2. ___________________________
3. __________________________ 4. ___________________________
12) When does deposition occur?
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13) What are the characteristics of constructive waves?
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14) Name four characteristics of spits
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15) How do spits form?
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16) What are sand bars?
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17) How do sand dunes form?
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18) Label the different parts of the sand dune system
Coastal Management
19) Describe three differences between hard and soft engineering management
strategies.
1. _________________________________________________________________________________
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2. _________________________________________________________________________________
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3. _________________________________________________________________________________
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20) Name one benefit and one cost of the following hard engineering strategies.
Sea Wall
Benefit _______________________________________________________________________________
Cost __________________________________________________________________________________
Gabions
Benefit _______________________________________________________________________________
Cost __________________________________________________________________________________
Rock Armour
Benefit _______________________________________________________________________________
Cost __________________________________________________________________________________
21) What is managed retreat? Why do some people think this is the best option?
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Coastal Management example
22) Why is coastal erosion occurring at your chosen example?
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23) What management strategies have been put in place at your chosen example?
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24) What conflicts occurred at your chosen example, Try and give at least two differing
viewpoints.
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Types of Rock
Rocks found on the Earth's surface actually come from inside the Earth - so they tell us a lot about
the Earth's interior. They are classified (organised) into three main groups: igneous rocks,
sedimentary rocks and metamorphic rocks.
Sedimentary rocks
A river carries, or transports, pieces of broken rock as it flows along. When the
river reaches a lake or the sea, its load of transported rocks settles to the
bottom. We say that the rocks are deposited. The deposited rocks build up in
layers, called sediments. This process is called sedimentation. The weight of the
sediments on top squashes the sediments at the bottom. This is called
compaction. The water is squeezed out from between the pieces of rock and
crystals of different salts form. The crystals form a sort of glue that sticks or
cements the pieces of rock together. This process is called cementation.
These processes eventually make a type of rock called Sedimentary rocks
contain rounded grains in layers. Examples of sedimentary rock are:
sandstone, chalk, limestone and shale.
The oldest layers of the rock are at the bottom and the youngest layers
are at the top. Sedimentary rocks may contain fossils of animals and plants trapped in the
sediments as the rock was formed. It may take millions of years for sedimentary rocks to form.
Igneous rocks
The inside of the Earth is very hot - hot enough to melt rocks. Molten (liquid)
rock forms when rocks melt. The molten rock is called magma. When the
magma cools and solidifies, a type of rock called igneous rock forms.
Igneous rocks contain randomly arranged interlocking crystals. The size of
the crystals depends on how quickly the molten magma solidified. The
more slowly the magma cools, the bigger the crystals.
If the magma cools quickly, small crystals form in the rock. This can happen if the magma erupts
from a volcano. Obsidian and basalt are examples of this type of rock.
They are called extrusive igneous rocks because they form from
eruptions of magma.
If the magma cools slowly, large crystals form in the rock. This can
happen if the magma cools deep underground. Granite is an example of
this type of rock. They are intrusive igneous rocks because they form from
magma underground. Unlike sedimentary rocks, igneous rocks do not
contain any fossils. This is because any fossils in the original rock will have melted when the
magma formed.
Metamorphic rocks
Metamorphic rocks are formed when other rock (igneous and
sedimentary rocks) are changed by heat and pressure. Earth
movements can cause rocks to be deeply buried or squeezed. As a
result, the rocks are heated and put under great pressure. They do not
melt, but the minerals they contain are changed chemically, forming
metamorphic rocks. Sometimes, metamorphic rocks are formed when
rocks are close to some molten magma, and so get heated up.
When a metamorphic rock is formed under pressure, its crystals become arranged in layers. Slate,
which is formed from shale, is like this. Slate is useful for making roof tiles because its layers can be
split into separate flat sheets. Marble is another example of a metamorphic rock. It is formed from
limestone. Metamorphic rocks sometimes contain fossils if they were formed from a sedimentary
rock, but the fossils are usually squashed out of shape.
An overview of the location of major river systems
An overview of the location of major upland/lowland areas
The long profile of a river and the cross profile of a river and its valley
A drainage basin is an area of land drained by the main river and its tributaries (small rivers).
Source is the start of a
river, which is usually
found in the upland
areas (hills and
mountains).
Tributary is a small river
joining the main river.
Confluence is where
two rivers meet.
Channel is where the
river flows.
Watershed is the higher land surrounding the river or drainage basin. Any precipitation falling
within the watershed flows into the river.
Mouth of a river is the end point usually into the sea or a lake.
The long profile of a river and the cross profile
of a river and its valley
A long profile shows the gradient of a river as it
journeys from source to mouth. The source of a
river is where it starts and the mouth is where is
meets the sea.
A river tries to achieve a smooth curve in order to
reach its base level at the sea. This is called a
graded long profile.
A cross profile is a section taken sideways across a
river channel and or a valley. A channel cross
profile only includes the river. A valley cross profile
includes the channel, the valley floor and the slopes
up the sides of the valley.
The diagram shows that as you move down the
long profile of a river the channel depth, width,
velocity, discharge and volume of load all
increases.
Whereas the load particle size, channel bed
roughness and the gradient of the channel all
decreases.
(Load the material the river carries)
Upper Course Middle Course Lower course
Steep gradient Gentle gradient Very gentle gradient
Shallow depth Deeper Very deep
Narrow steep sided channel Flatter channel with steep
sides
Flat channel with gentle
sloping sides
Quite fast velocity Fast velocity Very fast velocity
Steep v shaped valley U shaped valley Wide flat valley
Waterfalls and interlocking
spurs
Meanders and floodplains Meanders, oxbow lakes,
floodplains and levees
Fluvial processes – erosion; hydraulic action, abrasion, attrition, solution, vertical and lateral
erosion
1. Hydraulic Power. This is the force of water hitting the river
banks.
2. Abrasion. This is the sandpapering effect of rocks
scraping away at the river bed and banks.
3. Attrition. This is the process of rocks hitting each other in
the river and breaking into smaller rocks.
4. Solution. Some rocks are dissolved by water. For
example limestone and chalk, which form much of the UK landscape.
Vertical erosion is when the river erodes downwards, deepening
the river channel. It attacks the river bed. In the upper course the
river does not have enough energy to erode the land laterally
(sideways) so erodes almost entirely vertically.
Lateral erosion is when the river erodes width ways, widening the
channel. It attacks the river banks. In the lower course vertical
erosion continues however the river can also erode sideways
leading to a changing channel location.
Fluvial processes – transportation; traction, saltation, suspension and solution
Fluvial processes – deposition, why rivers deposit sediment
Deposition occurs in rivers when there is a decrease in velocity and the river slows down. This is
because as the river slows, the amount of energy decreases and the amount the river can carry
decreases too.
1. Large rocks get deposited in the upper course of the river as they are too heavy to be
carried far.
2. Smaller particles held in suspension are deposited when a river slows down, for example on
a river bend where there is greater friction.
3. Most deposition takes place at the mouth of the river where the river loses energy when it
meets the sea.
Solution
Characteristics and formation of erosion landforms; interlocking spurs, waterfalls and
gorges
Interlocking spurs are located in the upper course of the river, close
to the source of the river.
They are ridges of more resistant rock either side of the rivers
course. The velocity of the river is not strong enough to erode
through the spurs of land so has to travel around them.
Waterfall formation
Waterfall characteristics
As the waterfall continues to retreat upstream a
steep sided gorge is formed.
Characteristics and formation of erosion and deposition landforms; meanders and oxbow
lakes
The Thalweg is the fastest
line of velocity in a river. It
swings from the outside of
one bend to the outside of
the next bend.
The velocity is strongest on
the outside of the bend
causing erosion creating a
river cliff
The velocity is slower on the
inside of a bend causing deposition creating a river beach or a river slip off slope.
Cross section of a meander
This process of erosion on the outside of a bend and deposition on the inside of a bend causes the
river to move across the valley floor.
Oxbow lake formation
1. Erosion causes the outside of the
bends to get closer until there is only a
small bit of land left between them
called the neck.
2. During a period of flood, the neck of
the meander is broken through and
the river takes the course of least
resistance to form a new straight
channel.
3. Deposition eventually cuts the new
meander off forming an oxbow lake.
Characteristics and formation of deposition landforms; levees, floodplains and estuaries.
A flood plain is a flat area of land
either side of a river in its lower
course. When the river floods it
takes with it the load it carries.
(Rocks that have now turned into
silt – tiny particles of sand/mud.)
This mud is deposited on the land
when the river returns to its
channel after the flood. The
material left on the floodplain is
called alluvium.
The floodplain is built up over hundreds of years with each flood.
Levees
Levees are natural embankments (raised bits)
along the edges of a river channel. During a flood,
eroded material is deposited over the whole of the
flood plain.
The heaviest material is deposited closest to the
river channel because it gets dropped first when
the river slows down.
Over time the deposited material builds up
creating levees along the edges of the channel.
Estuaries
Estuaries are found at the mouth of a river where the river meets the sea. The land is close to sea
level and the valley is at its widest.
The water here is tidal, the river rises and falls each day with the tides.
The water floods over the banks of the river carrying the silt and sand it is carrying and deposits them
on the valley floor.
As the tide reaches its highest the water is
moving very slowly so the sediment is
deposited.
Over time more and more mud and silt builds
up creating large areas of mudflats.
At low tide the mud flats can be seen.
An example of a river valley in the UK to identify major landforms or erosion and deposition
The River Tees is located in the north of
England. It flows east from its source in
the Pennines to its mouth, on the North
Sea coast.
The source of the River Tees is Cross
Fell in the Pennines.
In its upper course, the River Tees flows
over hard, impermeable rocks.
Vertical erosion has formed classic V-shaped valleys. The
image below shows interlocking spurs close to Cauldron
Snout.
The UK’s largest waterfall, High Force, is located in the
upper course of the River Tees. An area of hard rock,
called Whin Sill (or Whinstone), is located above a layer of
soft rocks (sandstone and shale) and together they create
the waterfall.
As the River Tees reaches its middle course
lateral erosion overtakes vertical erosion and is evidenced
by winding meanders. Meanders in the lower course are
much larger. Oxbow lakes have formed in some areas. The
town of Yarm is found in the inside of a meander.
In the lower course, The River Tees has a large estuary with
mudflats and sandbanks.
How physical and human factors affect flood risk; precipitation, geology, relief and land
use.
River floods usually occur after a long period of rainfall, often during the winter. The volume of water
steadily increases causing the river levels to rise. Eventually the river may overtop its banks to cause
a flood. Sudden floods can occur after torrential storms. These are called flash floods. These are
often associated with heavy thunderstorms in the summer.
Physical Factors Human Factors Precipitation – a sudden heavy downpour can
lead to flash floods or long periods of steady
rainfall can lead to flooding or when large
amounts of snow melts it can cause flash floods.
As towns and cities grow new pavements,
roads, shopping centres, schools, leisure
centres are built. The greater the area covered
by buildings and roads, which have
impermeable surfaces the greater the flood risk. Geology – Clay soils and impermeable rocks
such as granite doesn’t allow water to soak
through (infiltrate) so the water builds up on the
surface, increasing surface run off and flooding
Felling trees (deforestation) can also leave the
soil being exposed to the heavy downpours.
This can result in soil runoff in to the rivers,
leading to rivers building up their river beds and
reducing the volume of the river channel.
Relief – The shape of the land can sometimes
cause flooding. Steep slopes will result in a
quicker run off in to the river often causing
flooding Low lying lower course areas are prone
to flooding as there isn’t often enough gradient
to remove the excess water
As large scale intensive market gardening is
increasing (e.g. growing tomatoes and fruits),
fields are getting replaced with polythene
greenhouses. The greenhouses intercept the
rainfall but don’t have the ability to soak up
water.
The use of flood hydrographs to show relationship between precipitation and discharge
A hydrograph shows how a river is affected by
a storm. This helps to understand discharge
patterns of a particular drainage basin and
helps to predict flooding and plan flood
prevention measures.
A hydrograph shows two graphs - a bar chart
showing rainfall, usually from a storm and a line
graph showing discharge from before, during
and after the rain storm shown in the bar graph.
River discharge - the volume of water that flows
in a river per second. It is measured in cumecs
(cubic metres per second)
Peak discharge – The highest discharge in the period of time.
Lag time – The delay between the peak rainfall and the peak discharge. Lag time happens because
most rainfall doesn’t land directly in to the river channel, there’s a delay as rainwater gets to the
channel. It either gets there flowing quickly overland (surface run-off) if the ground beneath it is
impermeable, which will mean a short lag time and a higher chance the river will flood or by soaking
into the ground (infiltration) which will mean a slower lag time with the river is less likely to flood.
Rising limb – The increase in the river discharge as rainwater flows in to the river.
Falling limb – The decrease in river discharge as the river returns to it normal level.
Basically, a hydrograph shows you the ways
in which a river is affected by a storm. This
helps us to understand discharge patterns of
a particular drainage basin and helps to
predict flooding and plan flood prevention
measures.
As you can see in the graph, the peak rainfall
is the time of highest rainfall. The peak
discharge is the time when the river reaches
its highest flow. There is a delay because it
takes time for the water to find its way to the
river. This is called lag time.
The normal (base) flow of the river starts to rise
when run-off, ground and soil water reaches
the river. This is shown on the hydrograph as the rising limb.
The falling limb shows that water is still reaching the river but in decreasing amounts. The run-
off/discharge of the river is measured in cumecs - this stands for cubic metres per
second. Precipitation is measured in mm - this stands for millimetres.
The costs and benefits of hard engineering management strategies; dams and reservoirs,
straightening the river channel, embankments and flood relief channels.
Hard engineering management strategies are where human made structures prevent or control a
river from flooding. These can be expensive to construct and are often used to protect areas of
high value landuse such as housing estates.
Dams - A huge wall built across a river usually in the upper course. A
reservoir (artificial lake) is stored behind the dam
Benefits
Reservoirs can store water especially during high rainfall therefore
reducing the risk of flooding.
The water in the reservoir can be used for drinking water, to generate
hydroelectric power and for water sports and recreation.
Costs
Dams are very expensive to build and the huge reservoirs
flood large areas of land.
The load the river carries is deposited in the reservoir instead
of as alluvium in the floodplains, causing the farmers’ fields to
be not as fertile.
Sometimes there can be design faults, like the Whaley bridge
dam. This resulted in the local town being evacuated
through fear of flooding if the dam broke.
Straightening the river channel / Channel straightening – The rivers course is straightened and
the meanders are cut out by building artificial straight channels
Benefits
Water moves along the course of the river quicker and
because it doesn’t need to travel as far there is less risk of
flooding. This reduces the chance of flooding in vulnerable
areas.
Costs
The concrete channels often look unsightly and are an
eyesore. Flooding may also occur downstream instead as the water is carried faster there. Due to
the speed of the water flow there may be also more erosion occurring downstream.
Embankments – Raised walls are built along the river beds.
Benefits
The river can hold more water as the river banks are higher
therefore increasing the channel size. This will protect the
buildings and landuse on the floodplain.
Costs
Embankments are quite expensive and there’s a risk of
severe flooding if the water rises above the level of the
embankments or if they break.
Flood relief channels. – Channels which are built to divert the water around important areas or
take it elsewhere if the water level in the river gets too high.
Benefits
Flooding is prevented in urban areas because the channel
redirects the river away from the area during periods of
heavy rainfall. Gates on the flood relief channels mean
that the water can be control as and when it is needed.
Costs
There will be increased discharge where the flood relief
channel re-joins the river, which could cause flooding in
that area. If the water level gets too high for the relief
channels they could also flood.
The costs and benefits of soft engineering management strategies; flood warnings and
preparation, floodplain zoning, planting trees (afforestation) and river restoration.
Soft engineering management techniques involves with the rivers natural processes to manage
flood risk. It aims to reduce and slow the movement of water into a river channel to help prevent
flooding.
Flood warning and preparation
This is where the Environmental Agency warns people about possible flooding
through TV, radio, newspaper and the internet. Warnings are given such as
Flood Watch – flooding of low lying land and roads is expected, Flood Warning
– there is a threat to homes and businesses and Severe Flood Warning – Extreme
danger to life and property is expected. Buildings are modified to reduce the
amount of damage a flood cause. People can make plans for what to do in a
flood, they can keep torches and blankets.
Benefits
The impact of flooding is reduced and gives
people time to prepare for the flood by
moving possessions upstairs, putting
sandbags at their doors or even evacuate.
People will worry less as they are not caught
unaware.
Costs
Warnings don’t stop the flood coming, and some people, especially the elderly may not be
aware of the oncoming flood risks. Some people may get a false sense of security and feel that
they would be ok in a flood. It’s expensive to modify houses to protect them from flood risks.
Floodplain zoning
Floodplain zoning is where
different landuse are
restricted to different
locations on the
floodplain. Areas closest
to the river and at high risk
of flooding can be kept clear of high value landuse such as housing and industry and are
instead used for parklands and playing fields.
Benefits
The risk of flooding is reduced, impermeable surfaces aren’t created e.g. buildings and roads. If
playing fields and parklands are closest to the river, there is no property to be damaged.
Costs
Floodplain zoning cannot be used in areas where landuse has already been built on. Also urban
areas cannot not be expanded if they are close to the river.
Planting trees (afforestation)
Planting trees to establish a woodland is called
afforestation. Trees obstruct the flow of water and slow
down the transfer of water to the river channel. Water is
soaked up by the trees or evaporated from leaves and
branches.
Benefits
Discharge and flood risk are reduced. Vegetation reduces
soil erosion in the valley and provides habitats for wildlife. Tree planting is also relatively cheap and
looks natural, blending in with the surroundings.
Costs
The trees take time to establish and mature so will take many years to become effective. There will
be less farm land available with the increase in tree coverage.
River restoration
River restoration is when the river is made more natural
and returned to its original course. For example man
made embankments could be removed so the river can
flood the floodplain naturally.
Benefits
There is less risk of flooding downstream as discharge is
reduced. There is limited maintenance needed as the river is
left in its natural state and it is better for the environment as
habitats for wildlife develop.
Costs
Local flood risk can increase, especially if nothing is put in place to reduce or prevent flooding.
An example of a flood management scheme in the UK; why the scheme was required, the
strategy used and the social, economic and environmental issues
Flood management at Banbury
Why the scheme is required
Much of the town of Banbury with a population of 45,000 is built on the
floodplain of the River Cherwell a tributary of the River Thames. Banbury is
50km north of Oxford.
Banbury has had a history of flooding. In 1998 large flooding causes the
railway station and main roads to close.
£12.5 million of damage was caused.
More than 150 homes and businesses were affected.
In 2007 the town of Banbury was affected again by
widespread flooding.
The flood management strategy used at Banbury
In 2012 Banbury’s new flood defence scheme was
completed.
A 2.9k earth embankment was built parallel to the
M40 to create a flood storage area. The
embankment had a maximum height of 4.5km.
It’s capable of holding around 3 million cubic
metres of water.
Two flow control structures have been built to regulate the flow of the river. See above.
The flood storage area collects rainwater which would have otherwise caused flooding to
the town.
The A361 road has been risen and drainage beneath the road has been improved.
New earth embankments and floodwalls have been built to protect property and
businesses.
A new pumping station has been built to transfer excess rainwater into the river below the
town.
The social, economic and environmental issues of the flood management schemes
Social Economic Environmental The raised A361 route into
Banbury will be open during a
flood, to avoid disrupting
people’s lives
The cost of the scheme was
about £18.5 million.
Around 100,000 tonnes of
earth were required to build
the embankment. This was
extracted from nearby,
creating a small reservoir.
Quality of life for local people
is improved with new
footpaths and green areas
By protecting 441 houses and
73 commercial properties, the
benefits are estimated to be
over £100 million
A new biodiversity Action Plan
habitat has been created with
ponds, trees and hedgerows.
Reduced levels of anxiety and
depression through fear of
flooding
Part of the floodplain will be
deliberately allowed to flood if
river levels are high.
River Landscapes in the UK
1) What does a river's long profile show?
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2) Label the long profile diagram below with the following labels; mouth, source,
middle course, lower course and upper course
3) Describe two differences between the cross profile of a river's lower and upper
course.
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8. _________________________________________________________________________________
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4) Name the part of the river course where vertical erosion is dominant.
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5) What's the difference between abrasion and attrition?
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6) Name the four different
types of transportation.
(Saltation, Suspension,
Solution, Traction)
7) When does deposition occur?
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Features of Erosion and Deposition
8) Where do waterfalls form? _______________________________________________________
9) The diagram below with the following labels; Hard rock, Soft rock, Plunge pool,
Overhang
10) Explain how waterfalls form
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11) What are interlocking spurs?
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12a) Where is the current fastest on a meander? ____________________________________
12b) What feature of a meander is formed where the flow is fastest?
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13) Name the landform created when a meander is cut off by deposition.
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14) What is a flood plain?
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15) What are levees and how do they form?
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16) What is an estuary? How do they form?
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Flooding and Flood Defences
17) What is river discharge?
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18) What is lag time?
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19) Label the flood hydrograph below with the following labels; Rising limb, falling limb,
peak rainfall, peak discharge, lag time.
20) What is the relationship between lag time and flooding?
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21) Describe two physical factors which can cause flooding
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21) Describe two human factors which can cause flooding
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22) Name 3 hard engineering management strategies to prevent river flooding.
1.__________________________________________________________________________________
2. __________________________________________________________________________________
3. __________________________________________________________________________________
23) Name 2 soft engineering management strategies to prevent river flooding.
1.__________________________________________________________________________________
2. __________________________________________________________________________________
24) What is the diagram below showing? How does it manage river flooding?
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