Human activities are frequently effected by physical systems on
the planet. In groups,write at least 3 ways that each system
(water, earth, air) can have an effect
Examples
Direct and indirect
Water:river floods, rain on crops, rising sea levels, water
supply, transport, power
Earth:soil type for agriculture, natural hazards (earthquakes,
volcanoes, mudslides), landforms for settlement (favourable or
hindering) or tourism
Air:tourism and leisure, agriculture (economic impact), travel,
money spent on predicting the weather, power
Life:food, resource for settlement and housing, transport,
aesthetics, economic
4. Energy from the Sun
The energy received from the sun radiated into space is known
as insolation.
This energy is sufficient to provide light and warmth for life
on this planet plus the heat to drive atmospheric and oceanic
movements
There are thus two major systems powered by solar energy: the
living system and the ocean-atmosphere system
Both are closed systems in that there is no exchange of mass
with the surrounding space system
However, both systems are dependent on materials supplied by
the solid Earth
5. The energy balance 6. The Hydrological System: Water on
Earth
The Earth is located in the habitable zone of the solar
system
5% (8 Million km) either way and water would not be able to
exist in its 3 states simultaneously
Earths mass allows gravity to hold an atmosphere
Water vapour and C02 in the atmosphere produce a greenhouse
effect which has helped maintain a steady state over geologic
time
7. 2. The Miracle of Water
All forms of life depend on water. It is central to:
Photosynthesis
Respiration
Enzyme function
Within conditions on the Earth, it has unique properties:
It is naturally occurring in all 3 states
It is a very strong solvent (the universal solvent)
It has a very high specific heat capacity (can buffer changes
in temperature)
Its solid form floats on its liquid form
8. 3. Water Availability & Use
70% of the Earths surface is water
Of this, 97% is in the oceans
Of the available 3% freshwater, over 75% is locked in polar ice
and glaciers
Only 1% of freshwater is easily accessible in lakes, rivers and
shallow soil moisture
Globally the average amount of water available per person per
year is 9000m3
By 2025 with the increase in population, this will drop to
5100m3 per person per year.
This would be enough if it was distributed evenly
9. 4. Distribution: Water Stores 10. Hydrology
The study of water and its properties including its
distribution and movement through the land areas of the earth
Principally concerned with the part of the cycle after the
precipitation of water onto the land and before its return to the
oceans
Hydrologists study the cycle by measuring such variables
as:
Precipitation
Ice and glacier stores
Water flow in rivers
Soil-water balance
Amount and flow of groundwater
11. Before we can understand the Hydrological cycle we need to
understand a little about weather 12. So it is hotter at the
equator but why??? 13. Where on earth receives the most year round
sunshine to provide good growing conditions? 1) Distance the suns
rays have to travel through the atmosphere Equator SunRays Longer
Distance Shorter Distance 14. 2) The curvature of the earth 15. 3)
The suns rays have to travel through thicker atmosphere at the
poles Thinner atmosphereThicker atmosphere 16. What causes it to
rain? 1) The sun heats up the sea.This causes water to be
evaporated (made into a gas called water vapour). 2) The warm air
full of water vapour rises high into the sky.Because it is so warm
it is very light, thats why it rises. 3) The higher up the air
gets, the colder it gets as well.This makes the water vapour
condense (turn back to liquid) and form clouds. 4) These clouds
eventually drop all of the water in them as rain. This type of rain
is called CONVECTIONAL rain 17. The UK is affected by a number of
different air masses.Air masses are huge blocks of air at different
temperatures.Some of the air masses arewarmand some of the air
masses arecold . 18. But air masses at different temperatures DO
NOT like one another so they wont mix together.Birmingham is
affected by cold air coming down from the north and warm air coming
up from the south. The junction between these two different air
masses is called afrontso when they cause it to rain it is
calledFRONTAL RAIN . 19. But if they wont mix, what happens when
they meet? 20. Its fair to assume then, that the final type of
rainfall will also follow the same process.But what is it that
iscausingthe air to rise? A FEW CLUES Name:RELIEF rainfall 21. Meet
Reggie, the RELIEF RAIN raindrop Reggieis a gas flying in the
air(water vapour)but when he meets a hill he has to climb over
it.It gets very cold near the top of the hill as he is so high and
Reggie changes from a gas to a liquid and settles into some
clouds(condensation). When lots of Reggies friends arrive in the
cloud it is too cramped to stay so some of them fall back to earth
as relief rainfall(precipitation). 22. The Hydrological Cycle 23.
Hydrological Cycle Matching Resurgence Overland Flow (surface
runoff Ground water flow Infiltration Surface water storage
Percolation Transpiration Isolation Precipitation Atmospheric Store
Snowmelt Saturated zone (aquifer) evaporation Soil moisture Ocean
store Base flow Atmospheric condensation Water table Volcanic water
Ice cap storage Human activities Interception Stream runoff
Impervious bedrock Reabsorbed by plants 24. The Drainage Basin
This is the area of land drained bya single riverand its
tributaries
Water drains downhill into a lake, river, dam, wetland, sea or
estuary
Theboundary (or watershed)is the ridge of high land, hill or
mountain beyond which any precipitation will drain into adjacent
basins
The drainage basin includes both the streams and rivers that
convey the water as well as theland surfacesfrom which water drains
into those channels
25. Drainage Patterns
Dendritic completely random like blood vessels
Trellis strong geology structure produces parallel forms with
right-angled tributaries
Deranged highly irregular often as a result of repeated
glaciations
Rectangular grid like pattern reflects tectonics faults or
bedrock joints
Parallel - often found in areas with steep relief or where flow
is over non-cohesive materials.
26. Nested Basins
This image shows the nested order of drainage basins.Rivers are
in blue
The red lines describe the watersheds for the drainage basins
of first order streams
The yellow lines define the watersheds for two drainage basins
from locations further upstream
Notethat the first order basins are components of these much
large drainage basins.