|Worksheet #22, ATOC 3600, November 14, 2000
1a. Suppose the radiative imbalance caused by increased atmospheric CO2 results in a 4 W m-2 warming. If all this energy goes into heating the atmosphere with no other changes, how quickly will the atmosphere warm. Note the radius of the Earth is 6.36 x 106 m and the area is 1.27 x 1014 m2.
Total heating is 1.27 x 1014 m2 * 4 W m-2
Total reservoir is 5.0 J gram-1 J K-1 x 106 x 1015 gram
The rate at which the atmosphere warms is equal to the heating rate divided by the reservoir size or 1.01x10-8 degrees per second or 0.3oK per year.
1b. Now imagine that once the atmosphere has warmed 5 degrees, half
of the radiative flux imbalance goes into heating the surface ocean, and
a quarter of the imbalance goes into heating the land surface. How quickly
does the surface ocean warm? How quickly does the land surface warm?
1c. Eventually, the atmosphere and surface ocean warm to a point at
which the entire radiative imbalance goes into heating the deep ocean.
How quickly will the deep ocean warm?
1d. Propose a change in low and high clouds that would mitigate
the radiative imbalance caused by the anthropogenic greenhouse warming
discussed above. In order to cool the globe most efficiently, should
an increase in clouds occur in the tropics, in the midlatitudes, or at
the poles? Is an increase in high clouds or low clouds most effective at
mitigating global warming?