Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

B Why does the Great Red Spot spin counter-clockwise?

  1. Aug 18, 2016 #1
    Jupiter's spins the same way the Earth does, so the Coriolis effect should make the Great Red Spot spin clockwise, but it's an anti-cyclone. Why is that?
     
  2. jcsd
  3. Aug 19, 2016 #2

    Orodruin

    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper
    Gold Member

    The clockwise spin (on the southern hemisphere) occurs around low pressure regions into which gravity will tend to pull gas.

    In a high pressure region, gas will try to flow away, resulting in the opposite rotation. Anticyclones occur on Earth too.

    The rotation is not only due to the Coriolis force, it is due to the interplay between Coriolis and gravity.
     
  4. Aug 19, 2016 #3
    Why does gas try to flow away in a high pressure region?
     
  5. Aug 19, 2016 #4

    Orodruin

    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper
    Gold Member

    Because the pressure gradient gives a resulting force on any volume of gas. It is just the same reason air generally would flow in to fill a vacuum if allowed.
     
  6. Aug 19, 2016 #5

    Orodruin

    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper
    Gold Member

    This image summarises it quite neatly:
    cyclones_and_anticyclones1322859004780.jpg
     
  7. Aug 19, 2016 #6
    Same as if you blow up a balloon.
    The air inside the inflated balloon is at a higher pressure than the outside atmosphere, so if you then open the air inlet up, the air inside comes back out again.
     
  8. Aug 19, 2016 #7
    So because of the high pressure the surrounding is trying to find equilibrium?
     
  9. Aug 19, 2016 #8
    Yes, the air masses are attempting to reach equilibrium.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Why does the Great Red Spot spin counter-clockwise?
  1. Jupiter's Giant Red Spot (Replies: 14)

  2. The great red spot (Replies: 8)

  3. Why does the world spin? (Replies: 12)

Loading...