Ask A Scientist© Weather Archive

name         Joe
status       student
age          18

Question -
Because of the nature of the earth's elliptical orbit, the planet recieves
its largest share of solar heating during the southern hemisphere summer
and its smallest share of solar heating during the sothern hemisphere
winter.  And yet the northern, hemisphere, on average experiences greater
extremes in temperature than the southern hemisphere.  Why?  Does it have
to do with the atomosphere or maybe the oceans circulation?

Joe,

On reason for the greater variation (extremes in the maximum
temperature values in the northern hemisphere perhaps;
I don't know about the minimums - I think that Antarctica
has the lowest temperatures) is the larger amount of land
area in the northern hemisphere as opposed to the larger
amount of ocean in the southern hemisphere.  Oceans are a
huge stabilizing force for energy distribution and therefore
are very effective in limiting temperature variations in
the southern hemisphere.

David Cook
meteorologist
Argonne National Laboratory
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