Earth Systems, Structures and Processes

{ 7.E.1.

Students will be able to understand how the cycling of matter (water and gases) in and out of the atmosphere relates to Earth’s atmosphere, weather and climate and the effects of the atmosphere on humans.

Students will be able to compare the composition, properties and structure of Earth’s atmosphere to include mixtures of gases and differences in temperature and pressure within layers. ---Objective 7.E.1.1.

Atmosphere : a blanket of air surrounding Earth 1. What is air?

2.

What is air made up of? 3.

The atmosphere is a mixture of gases. The amount of each gas is usually very constant from the surface of the planet up to the top of the troposphere.

http://sunshine.chpc.utah.edu/labs/atmosphere/at m_gases1.html

Atmospheric Gases

Processes that keep the mixture of gases constant: 1. respiration 2. photosynthesis 3. evaporation 4. condensation 5. weathering of rock 6. decay of organic matter-

Gases are constantly being used and renewed.

     The atmosphere has different properties at different elevations and different locations around the Earth.

The atmosphere’s density decreases as you travel upward. **Most of the mass of the atmosphere is close to Earth’s surface!

The air pressure is less on top of the mountains than in valleys.

At the equator the atmosphere is warmer, at the poles it is cooler.

The uneven heating of land and water causes a rising and sinking of warm and cool air masses, creating convection currents and causing winds. **This creates our weather!

Properties of the atmosphere

Like a hamburger!

http://its.guilford.k12.nc.us/act/grade7/gr7_files/a tmos/layers.ppt

Temperature layers http://www.pbs.org/wgbh/nova/balloon/science/a tmosphere.html#troposhere

Layers of the Atmosphere

The Carbon Cycle Living things take part in a repeated process of gas exchange with the atmosphere.

Nitrogen Cycle You and all other living things participate in ongoing processes.

Water Cycle Ongoing processes modify the atmosphere.

1.

2.

3.

Volcanic eruptions Forest fires Dust storms Dramatic events cause sudden changes in the atmosphere.

Solar Radiation can be absorbed or reflected by Earth’s surface, clouds, and the atmosphere.

It provides heat and light.

Energy is moved throughout the atmosphere by radiation, conduction, and convection.

The Sun supplies the atmosphere’s energy.

Types of radiation: 1.

2.

3.

Visible light Ultraviolet radiation Infrared radiation The ozone layer in the stratosphere layer protects life from harmful radiation.

Gases in the atmosphere absorb radiation.