Greenhouse gases and climate change

Question 1

What are some examples of greenhouse gases?

Answer 1

carbon dioxide, methane and water vapour

Question 2

what do greenhouse gases do for the atmosphere?

Answer 2

they act as an insulating layer in the earth’s atmosphere - this amongst other factors allows the earth to be warm enough to support life

Question 3

what is the greenhouse effect?

Answer 3

-greenhouse gases absorb long wave (not short) radiation that gets reflected back off the earth.
-They then re-radiate it in all directions including back towards earth
-The longwave radiation is thermal radiation so it results warming of the surface of the earth

Question 4

How can human activity affect the amount of greenhouse gases in the atmosphere?

Answer 4

-Deforestation: fewer trees means less CO2 is removed from the atmosphere via photosynthesis
-Burning fossil fuels: Carbon that was ‘locked up’ in these fuels is released as CO2
-Agriculture: more farm animals produce more methane through their digestive processes
-Creating Waste: more landfill sites and more waste from agriculture means more CO2 and methane released by decomposition of waste

Question 5

What do scientists believe is currently happening to the earth’s climate and how do we know the evidence is reliable?

Answer 5

-they agree that the extra carbon dioxide from human activity is causing increase and that this will lead to climate change
-evidence for this has been peer reviewed and is therefore reliable

Question 6

why is it so hard to fully understand the earth’s climate?

Answer 6

-it is so complex and there are so many variables that its hard not to make an oversimplified model
-this has led to speculations in the media where stories may be biased or only some of the information given

Question 7

what are some of the dangerous consequences of climate change predicted to occur?

Answer 7

-an increase in global temperatures could lead to ice caps melting causing a rise i sea levels, increased flooding and coastal erosion
-changes in rainfall patterns may cause some regions to get too much or too little water. This, along with changes in temperatures may affect the ability of a region to produce food
-the frequency and severity of storms may increase
-changes in temperature and water availability in a habitat may impact wild species leading to differences in distribution