Lesson 9. Greenhouse Effect & Climate Change
Class Discussion: What is the Greenhouse Effect?
The greenhouse effect is warming of the Earth caused by solar radiation being trapped by the
atmosphere. Solar radiation is mostly:
-Ultraviolet or invisible UV rays that can cause cell damage like sunburn or skin cancer.
- Infrared is mostly heat and is also invisible. Gases in the atmosphere trap some infrared
and it is bounced back and forth between the surface of the earth and the gasses. Picture
infrared heat as a thousand bouncy balls bouncing back and forth between the roof and
the floor of your classroom, warming everything they touch!
-Visible light is the part of the solar radiation that you can see. Gases in the atmosphere
let visible light pass through, bounce off the earth’s surface, and re-enter space.
Class Discussion: Which gases are greenhouse gasses?
Greenhouse Gasses are gasses that trap heat. They are:
Water Vapor – water in the air.
Carbon Dioxide – (CO2) Released by the burning of fossil fuels to create electricity and to
transport people and goods.
Nitrous Oxide – (N2O) Released by agriculture and combustion. Nitrous oxide is emitted when
farmers add nitrogen to the soil as a synthetic fertilizer.
Methane – (CH4) Released by the use of natural gas in homes, livestock, landfills, and
wastewater management systems and melting of the permafrost.
Ozone – (O3) A naturally occurring layer in the atmosphere, it protects living organisms from
harmful UV rays. Some chemicals released by people have depleted the ozone layer, causing a
“hole” in the ozone. The depleted area is the worst over Antarctica due to weather patterns.
Class Discussion: What is Climate Change? What effects does it have on the Earth?
Climate Change is caused by the rising average temperature of the Earth. The Earth gets warmer
as the greenhouse effect gets stronger, which happens when extra greenhouse gasses are added to
the atmosphere.
The effects of Climate Change:
Ocean: melting sea ice, rising sea level, rising sea temp, rising acidity of oceans, coral reef
destruction by bleaching.
Land: melting or receding glaciers, changes in animal migration.
Lesson 9. Greenhouse Effect & Climate Change
Weather: more extreme weather, more rain in some areas and drought in others.
Review Questions:
What is the difference between the greenhouse effect and climate change?
What causes the greenhouse effect?
What would the Earth look like without the greenhouse effect?
What are the effects of climate change?
What would happen if we had no ozone layer?
Worksheet & Activity: Hand out The Greenhouse Effect worksheet and have kids take notes as
they follow along in the discussion. Color if time allows.
Vocab:
Solar radiation is mostly:
-Ultraviolet or invisible UV rays that can cause cell damage like sunburn or skin cancer.
- Infrared is mostly heat and is also invisible.
-Visible light is the part of the solar radiation that you can see.
Fossil fuels are created by the decomposition of ancient dead organisms. They are a nonrenewable resource. Examples are oil, coal, petroleum, and natural gas.
Rising acidity: About one-third of the carbon dioxide emitted by human activity has already been
taken up by the oceans. As carbon dioxide dissolves in sea water, carbonic acid is formed, which
has the effect of acidifying the ocean, measured as a change in pH.
Receding glaciers lose more snowpack every year than they gain, meaning they will eventually
disappear.
Bleaching of coral reefs is caused by small but prolonged rises in sea temperature, forcing coral
colonies to expel their symbiotic, food-producing algae. This kills the reef and turns it white.