Identify and analyze the way fossil fuel combustion has changed the composition of Earth's atmosphere, and the way this change has affected climate.(4 points)
Fossil fuel combustion has had a significant impact on the composition of the Earth's atmosphere and the climate. Here are some key points to consider:
1. Increased greenhouse gas emissions: Fossil fuel combustion releases carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) into the atmosphere. These three gases are the primary greenhouse gases responsible for trapping heat in the Earth's atmosphere and causing the greenhouse effect. As the burning of fossil fuels has increased since the industrial revolution, these greenhouse gas concentrations have also significantly increased, leading to an enhanced greenhouse effect.
2. Rising CO2 levels: The burning of fossil fuels, such as coal, oil, and natural gas, has led to a substantial increase in atmospheric carbon dioxide levels. Prior to the industrial revolution, CO2 concentrations were around 280 parts per million (ppm). Today, they have surpassed 400 ppm, which is the highest level in at least 800,000 years. This increase is primarily due to the combustion of fossil fuels.
3. Impact on climate change: The increased greenhouse gas emissions from fossil fuel combustion have resulted in a significant rise in global temperatures. The enhanced greenhouse effect caused by the accumulation of CO2 and other greenhouse gases has contributed to global warming. This warming leads to various climate change phenomena such as melting ice caps and glaciers, rising sea levels, more frequent and severe weather events (e.g., heatwaves, storms, hurricanes), and shifts in precipitation patterns.
4. Feedback loops: The changes in the Earth's atmosphere due to fossil fuel combustion can also trigger feedback loops that further amplify climate change. For example, the melting of Arctic ice due to global warming reduces the amount of reflective surfaces and exposes darker ocean waters. This, in turn, increases the absorption of sunlight, causing further warming. Additionally, as permafrost thaws due to global warming, it releases methane, a potent greenhouse gas, further contributing to the warming effect.
Overall, fossil fuel combustion has acutely altered the composition of the Earth's atmosphere by increasing greenhouse gas levels, particularly carbon dioxide. This has resulted in climate change, including rising temperatures, extreme weather events, and other significant impacts. Addressing and reducing these emissions are crucial steps towards mitigating the impacts of climate change.