Explain how the use of fossil fuels and changes in agriculture may have contributed to global changes in temperature (4 marks)

When fossil fuels are burnt, they release carbon dioxide. Carbon dioxide is a greenhouse gas which traps incoming radiation from the sun. This radiation causes the atmosphere to heat up and thus we see an increase in global temperatures. Agriculture requires lots of land, to make way for this land, forests are often cut down. Deforestation will lead to an increase in greenhouse gases as there are fewer trees to absorb some of the atmospheric carbon dioxide. Also, livestock release methane which is another greenhouse gas. Finally, fossil fuels are burnt in the transportation of food and also in the processes of agriculture which again releases carbon dioxide.