REPLY


QUESTION: On Jupiter, why doesn't the hurricane die out?

ANSWER from Chris Ready on April 24, 1996
  That's an interesting question.  Sometimes, the best way to understand weather
phenomena on other planets is to compare them with how weather behaves here.
On Earth, hurricanes allways form out at sea, where there is ample moisture
available
to mix in with the air, helping to give rise to powerful hurricanes.  These
hurricanes remain strong when at sea, but once they hit land, they begin to
loose
their water "fuel" to keep them going.  As a result, if a hurricane continues 
overland, it will die out after it looses its source of water.
  How does Jupiter as a planet differ from Earth?  Would this allow hurricanes
to die out?

Answer: Since Jupiter does not have a landmass, low pressure cells can bring in
as much moisture from the surrounding clouds as they wish. In effect, Jupiter's
hurricanes draw from a continuous "sea" of "fuel". With no landmass to
interuppt the 
hurricane from feeding itself, hurricanes on Jupiter can run on perpetually.  In
fact, the Great Red Spot is believed to have existed for as much as 500 years so
far (and is about twice the size of the earth)!