The
Climate Machine: Heat Reservoirs
Processes such as sunlight, evaporation, conduction,
mixing and longwave radiation are constantantly redistributing energy within
the Earth system. Here is a table that summarizes the global average magnitude
of the energy reservoirs and transfers.
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the rate at which temperature can change in a reservoir,
dt, is given by
dt = Cp M dT / L
The text gives the following example.
If the Sun is shut off completely,
the net loss of heat L (from the top left corner of Figure 11.15) is (5.0-0.4)=4.6
x 1016 J. A change, dT, of 10 degrees C would take about 3.2
x 107 seconds or 1 year since Cp = 4 J/(goC)
and M=3.8x107x1015g.
The land would take much less time since its total mass
is less at about 104 x 1015
g giving a change of 10 oC in 2.2 x 104
sec or about 6 hours.
For details about the cryosphere, go
here.