Topic 9 Flashcards
What is the air made up of
Nitrogen=78% Oxygen=21% Carbon dioxide =0.04% Argon=0.9% And other small amounts of gases including water
Global warming
Increasing levels of greenhouse gases in the atmosphere, which is warming up the earth too much
Greenhouse effect
Greenhouse gases in the atmosphere maintain temperatures on Earth high enough to support life
What are the greenhouse gases
Water vapour (H2O) Carbon dioxide (CO2) Methane (CH4)
What do the greenhouse gases do
The sun emits short-wavelength radiation which warms the Earth
The Earth loses heat by emitting long-wavelength radiation
Greenhouse gases absorb some of the long-wavelength radiation
They re-radiate this thermal radiation in ALL directions including back to Earth. This warms the atmosphere
What would happen if there were no greenhouse gases
The Earth would be too cold to support life
How is carbon dioxide increasing
BURNING FOSSIL FUELS FOR ENERGY/ELECTRICITY-Combustion of propane
DEFORESTATION -Cutting down trees reduces the amount of carbon dioxide absorbed from the atmosphere by photosynthesis
Combustion of propane equation
Propane+Oxygen—>Carbon dioxide+Water
C3H8+5O2–> 3CO2+4H2O
How is methane increasing
CATTLE PRODUCTION-Cattle reared for humans, to eat as beef or milk, produce methane
LANDFILL SITES-The decay of waste in landfill by microorganisms produce methane
GROWING RICE-Has a lot of water sitting in it, produces methane
Carbon footprint
The total amount of carbon dioxide and other greenhouse gases emitted over the full life cycles of a product, service or event
Pollution
The presence of harmful or poisonous substances in the environment OR an increased level of a particular substance that has negative environmental effects
Pollutants
Harmful or poisonous substances the cause pollution
