1. Describe what a greenhouse gas is and give examples of the common greenhouse gases. Why are greenhouse gases important to surface energy balance?
A greenhouse gas is a gas in an atmosphere that absorbs and emits radiation within the thermal infrared range. This process is the fundamental cause of the greenhouse effect
Examples of common greenhouse gases are water vapor, carbon dioxide, methane, nitrous oxide, Chlorofluorocarbons, and ozone.
Greenhouse gases strongly absorb the earth’s thermal infrared radiation, so they blanket the earth and reduce the cooling of the earth to space.
Without these so-called greenhouse gases, the surface of the earth would be about 30 degrees Celsius cooler, it is too cold for life to exist.
2. What is shortwave radiation? What is longwave radiation?
Shortwave radiation is basically radiant energy (light) in the visible, near infrared ...view middle of the document...
Trend: In my opinion, the urban industry has a big impact on the exhaust of CO2. Coal and fossil fuel burn release huge amount of CO2. The modern activities have speed up the producing of CO2. Forest fire also has a big impact on the CO2 level increase. The massive tree burn can also release CO2 in a big amount. That is my opinion for CO2 increase.
Seasonality: During the fall and winter, vegetation stops growing and decays, leading to higher amounts of carbon dioxide in the air. Vegetation then begins to grow during the spring and summer, absorbing some of the atmospheric carbon dioxide.
4. What is albedo? What is the averaged albedo of the Earth? If you replace urban surface (albedo is about 0.20) to the original forests (say, albedo is 0.40), how would the surface temperature change?
Albedo is the ratio of the outgoing solar radiation reflected by an object to the incoming solar radiation incident upon it.The average overall albedo of Earth is 0.39. If you replace urban surface (albedo is about 0.20) to the original forests (say, albedo is 0.40), the surface temperature will increase.
5. Get the annual global land temperature anomalies from http://www1.ncdc.noaa.gov/pub/data/
a. Plot the data in 2-dimention figure
b. Which year was the hottest year and which was the coldest year?
The hottest year was in 2007 and the coldest year was in 1984
c. Do you see any global warming signal from the data? Explain in 2-5 sentences.
Yes, I do see global warming. It shows very clear in the graph. The trend is up toward to the right corner. Since 1880, the temperature changed from a negative numbers to positive numbers. It is not an accident that the hottest years were all after year 2000. The temperature on earth is rising. We are experiencing global warming.
Supplemental reading for problem 5:
“Global Surface Temperature Anomalies”