Q1) Understanding Earth’s energy balance is essential to understanding the issue of global warming. For example, the solar energy striking Earth’s surface averages 168 watts per square meter (W/m2), but the energy leaving Earth’s surface averages 390 W/m2. Why isn’t Earth cooling rapidly?
Answer:
Even though the amount of energy emitted from the Earth’s surface is more than double the amount received from the Sun, the Earth does not cool rapidly because the Earth’s surface absorbs a large amount of energy from the atmosphere.
Q2) Decide and explain where the statement is correct or incorrect.
Answer:
The statement is incorrect for a number of reasons. First, the two people are assuming that just because their winter is colder than usual, global warming, which is a global phenomenon, must not be as severe as previously thought. They have confused weather, which refers to day-to-day changes, with climate, which refers to long-term patterns. In this case, the people assume the weather they are experiencing at the moment can be generalised to describe global climate patterns. Second, they do not realise that the heavy snowfall they are experiencing could in fact be a result of climate change brought about by global warming, as climate change results in more extreme weather.
Q3) One of the first radar devices developed during World War 2 used microwave radiation of a specific wave range that triggers the rotation of water molecules. Why was the design not successful?
Answer:
It was because the absorption of microwave radiation by H2O in the atmosphere interferes with the detection of intended objects.
Q4) Now that you have studied air quality (Unit 1), stratospheric ozone depletion (Unit 2) and global warming (Unit 3), which do you believe poses the most serious problem for you in the short run (pick one and explain)? In the long run (pick one and explain)?
Answers:
Short run: Though the burning of fossil fuels contributes to global warming and decreased air quality, air quality has a direct impact on our everyday lives and can affect human health over a much shorter time frame than processes such as global warming. It is thus more of a concern in the short run.
Long run: Though ozone depletion and global warming are caused by human activities, there are already many regulations targeted at reducing the amount of chlorine, which depletes ozone, in the air. However humans as a whole are still burning fossil fuels which generate CO2 which contributes to global warming. The effects of global warming, which includes climate change, are also visible through climate patterns which can only be observed over longer periods of time.