Earth Systems and Patterns 

The scientific theory of the evolution of Earth states that changes in our planet are driven by the flow of energy and the cycling of matter through dynamic interactions among the atmosphere, hydrosphere, cryosphere, geosphere, and biosphere, and the resources used to sustain human civilization on Earth.

EARTH’S SPHERES

ATMOSPHERE• Energy:

– Sun is the source for 99% of heat energy on Earth.• 25% - reflected by

atmosphere• 5% - reflected by

ice and snow• 25% - absorbed by

atmosphere• 45% - absorbed by

Earth’s surface

• Energy Transfer– Energy is transferred

3 ways (see Big Idea 11-7th grade for more information)

• Conduction – particles must touch to transfer energy.

• Convection - particles circulate to transfer energy.

• Radiation – energy travels in the form of waves.

– Example: Greenhouse Effect

“WATER, WATER, EVERYWHERE”

HYDROSPHERE• Includes all of the water

on Earth found in streams, lakes, the soil, groundwater, and the air

• 71% of the Earth is covered by water.– Salt water = 97% (oceans)– Fresh water = 2.8%

(icecaps, glaciers, lakes, streams, groundwater)

CRYOSPHERE• Part of the Earth's

hydrosphere comprised of frozen water

• The cyrosphere is a sensitive element of the climate system providing a key indicator of climate change.

Water regulates the temperature on Earth.

The Water Cycle

• Water on Earth is recycled through the Water Cycle.

• The Water Cycle consists of the following activities: – Evaporation– Condensation– Precipitation– Percolation– Runoff– Transpiration

The Water Cycle

• A water cycle is the way water moves from the air to land

and back.

The sun’s heat makes water evaporate into water vapor.

• The water vapor rises into the air, cools, and condenses into tiny droplets of water.

• The drops of water come together to form clouds.

The water drops become heavy and fall as rain, sleet, snow, or hail.

The rain falls or snow melts and flows to rivers, lakes, and oceans.

Precipitation

Condensation

Evaporation is when a liquid changes to a gas.

Water Cycle

WHY THE WATER CYCLE IS IMPORTANT

LITHOSPHERE

• The Earth's solid surface, often called the crust of the Earth.

• Included are: continental and oceanic crust as well as the various layers of the Earth's interior

BIOSPHERE

• Contains all life on Earth, including human, and all organisms

• The biosphere extends to any place that life (of any kind) can exist on Earth.

• This layer relies on a continuous supply of energy from the sun.

• Contains the factors needed for life:– Water– Moderate temperature– Food source

• Energy is in constant flow throughout the Biosphere.– Animals/plants break

down and decompose.– Elements such as carbon

dioxide and nitrogen are released.

– Resources are used over again – Carbon/Nitrogen Cycles.

CARBON CYCLE• Every living thing

contains carbon.• Importance:

– Photosynthesis – uses carbon dioxide and gives off oxygen (producers).

– Respiration – uses oxygen and gives off carbon dioxide (consumers).

NITROGEN CYCLE• Nitrogen is found in

our atmosphere.• It provides soil with

nutrients.• Plants and animals

use nitrogen.• When plants/animals

decompose in/on the ground, nitrogen seeps in creating fertile soil.

SPHERE RECAP

– Lithosphere - All processes associated with the solid earth

– Hydrosphere - All processes associated with water

– Atmosphere - All processes associated with the gases that envelope the earth

– Biosphere - All processes that involve living organisms

• If a change in a sphere happens, a chain reaction could take place in Earth’s Cycles

• Earth’s Cycles include:– Water– Carbon– Nitrogen

KNOWLEDGE CHECK

1. Name 4 Earth’s spheres.

2. How is energy transferred throughout the atmosphere?

3. What two cycles occur in the Biosphere?

CLIMATE and WEATHER

What Causes Climate?

• Overall/average temperature and precipitation for an area

• Climate is determined by two basic factors: – temperature

– precipitation

CLIMATE FATORS

TEMPERATURE

• Average KE of molecules– High Temperature=

increase movement of molecules= feels hot

– Low Temperature= decrease movement of molecules= feels cold

PRECIPITATION

• When a droplet reaches a certain critical mass, the force of gravity will exceed the other making precipitation fall.

• Types of precipitation: – Rain– Snow– Sleet– Hail

Climate Zones

• The Earth’s climate can be divided into 3 climate zones.

– Based on average temperatures

• 3 major climate zones on the Earth – Polar– Temperate – Tropical zones.

POLAR CLIMATES

• The average yearly temperature is below freezing.

• Even during the warmest months of the year, the temperature does not go over 10°C

TEMPERATE CLIMATE

• Located between the tropics and the polar tropics

• Generally contains four seasons• Climate can be broken down into four

categories:– Oceanic– Mediterranean– Humid subtropical– Continental World map with temperate zones

highlighted in red.

TROPICAL CLIMATE

• Cover the largest area of Earth• Experience hot and humid weather• Much rainfall• Seasons are defined by precipitation.

CLIMATE OVER TIME

• There are three natural factors responsible for climate change over time:

1. Slow drifting of the continents

2. Changes in the sun’s energy output

3. Variations in the position of the Earth relative to the sun

• Changes related to human activity1. Burning of fossil fuels

A petrochemical refinery in Grangemouth, Scotland, UK

KNOWLEDGE CHECK

1. What determines the overall climate of a specific area?

2. List 3 factors that contribute to climate change.

WHAT IS WEATHER?

• The current state of the atmosphere ...what is happening right now.

KEY IDEAS ABOUT WEATHER

• The sun warms the Earth’s surface and all the air above the surface.

• Earth’s highest temperatures are at the equator and the coldest at the poles.

• The air above land is warmed more quickly than air above water.

• Warm air expands and rises, creating an area of low pressure; cold air is dense and sinks, creating an area of high pressure.

TODAY THE WEATHER IS…

• Conditions that affect weather: –Temperature–Pressure–Moisture content–Winds

TEMPERATURE

• Three natural factors that affect the temperature of a particular location:– Latitude – Elevation – Presence of ocean and land

• Warm air is light - rises up.• Cold air is heavy – sinks.

TEMPERATURE Land

• Organic materials such as plants and animals tend to absorb energy.– Air temperature in a

forest is usually cooler than the temperature in a desert.

• Desert area tends to reflect energy.– Air temperature can be

raised by as much as 10 degrees.

Ocean• Water absorbs vast amounts of

energy from the sun. Likewise, bodies of water release energy very slowly. For this reason, areas near water are usually more mild.

• Because of water’s ability to absorb heat, store it, and release it later, the Earth’s oceans have an important role in helping to moderate its temperature.

KNOWLEDGE CHECK

1. What is the difference between weather and climate?

2. What are the four factors that influence weather?

3. How does the temperature of land differ from the oceans?

WHAT IS WIND?

• When there is a difference in air pressure in the atmosphere, wind is created.– Unequal heating causes changes in air

pressure.• Wind always moves from areas of

high pressure to areas of low pressure.

THE JET STREAM• Fast flowing, narrow

air currents found in the atmospheres between the troposphere and the stratosphere

• Caused by heating of the Earth and its rotation

• These winds flow from west to east around the world.

Jet streams flow from west to east in the upper portion of the troposphere.

GLOBAL WIND DIRECTION

• Coriolis Effect – Rotation of the Earth causes moving air and water to change directions.

• Northern Hemisphere winds curve to the right.

• Southern Hemisphere winds curve to the left.

WIND SPEED

• Result in a large pressure difference

• Strong winds also occur in low latitudes due to stronger heating and greater pressure differences. – Hurricanes and tornadoes are

examples.

KNOWLEDGE CHECK

1. What must be different for wind to occur?

2. What is the Jet Stream?

3. What helps move winds around the globe?

4. What factor determines wind speed?