Chemistry of the atmosphere Flashcards
How did the atmosphere form
4.6 billion years the Earth formed
There was a lot of volcanic activity
Volcanoes released carbon dioxide and water vapour
At this point the atmosphere was similar to Mars and Venus
Water vapour condenses to form the oceans
About 2.7 billion years ago, algae evolved in the oceans and carried out photosynthesis which released carbon
What is the atmosphere made of
Approximately 20% oxygen
Approximately 80% nitrogen
Other gases such as carbon dioxide, water vapour and noble gases
How has carbon dioxide levels decreased
Dissolves in oceans:
Animals/fish use compounds to make shells/skeletons
Animal/fish die. Sediment forms
Shells/skeletons become sedimentary rocks
Used in photosynthesis:
Algae/plants absorb it
Algae/plants decay under high temperatures and pressures
Crude oil and natural gas forms
What are greenhouse gases
Absorb long wavelength infrared radiation given off by the Earth but doesn’t absorb the sun’s radiation
Carbon dioxide
Methane
Water vapour
How does the greenhouse effect work
Radiation from the sun reaches the Earth
Some radiation is reflected back from the surface
The rest is absorbed by the surface and re-radiated as infrared radiation
Greenhouse gases in the atmosphere absorb infrared radiation
The radiation is reflected in all directions, warming the Earth
How do humans increase the greenhouse
Carbon dioxide:
Deforestation
Fossil fuels
Methane:
Manure
Landfill
What is the difference between global warming and climate change
Global warming - an increase in the temperature at the Earth’s surface
Climate change - long term change in weather patterns
What are the effects of global warming
Glaciers melting
Sea levels rising
Habitats changing
What is carbon footprint
A measure of how much carbon is used through the activities of a person, company or country
What is the carbon footprint for a plastic bag
Drill for crude oil
Fractional distillation of crude oil
Provide high temperatures to make poly(ethene)
Transport bags to shops
Transport bag to landfill
Burning bag after disposal
What are ways to reduce carbon footprint
Alternative energy
Carbon offsetting (planting trees when you produce CO2)
Carbon capture ( storing CO2 doesn’t enter the atmosphere)
Energy efficiency
Carbon taxes (government taxes to company)
What is carbon neutral
No extra CO2 is added to the atmosphere
What is the problem with scientific research for reducing carbon footprint
Scientists don’t all agree about the causes and consequences of global climate change
What is the problem with economic consideration for reducing carbon footprint
Many of the methods for reducing climate change are expensive
What is the problem with incomplete international cooperation for reducing carbon footprint
The Kyoto Protocol is a major international treaty agreed by many nations to reduce emissions of greenhouse gases
