To a rough approximation, the Earth can be treated as a greybodysphere with uniform temperature, absorptance ? = 0.70 andemissivity ? = 0.61. The low absorptance is largely due toreflection of the incoming sunlight by clouds and ice, while thelow emissivity is largely due to greenhouse gases in theatmosphere.
a) Over timescales of decades, the total solarirradiance at the Earth varies between about 1360.3 W/m2and 1362.0 W/m2 . Using the greybody Earthapproximation, how large of a temperature change can be expecteddue to these natural changes in solar irradiance? [Answer in K as apositive number.]
b) Over the last century, the amount of CO2 inthe atmosphere has increased dramatically, which has resulted in achange in ? from 0.62 to 0.61. Using the greybody Earthapproximation, how large of a temperature change can be expecteddue to this change in emissivity? [Answer in K as a positivenumber.]
NOTE: The answers to a) and b) are NOT 0.1K
