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Jupiter’s Great Red Spot Experiences Shrinkage

It’s kind of like a wool sweater that’s been put through the dryer. Except the sweater is a hurricane-like storm as wide as three Earths, and the dryer is Jovian climate change.


—Image courtesy NASA/JPL/University of Arizona

From 1996 to 2006, Jupiter’s Great Red Spot shrank by about 15 percent, according to researchers at the University of California, Berkeley, who measured the size of the storm based on wind speed and direction.

“We don’t fully understand all the sources of energy, or the ways the Red Spot loses energy,” study co-author Xylar Asay-Davis told Space.com.

“But these can become slightly imbalanced for a period of time, and this is likely to be what is causing the Red Spot to shrink—less energy is being fed in and more is slowly dissipating away.”

Asay-Davis and colleagues think ongoing climate change on Jupiter may be at the root of the energy imbalance.

These changes became especially noticeable between 2005 and 2007, when Jupiter went through a major atmospheric tantrum—the Impressionist cloud cover changed hues and several white oval storms suddenly morphed into brick-red mini versions of the iconic spot.


—Image courtesy NASA/JPL

Scientists suggest this upheaval was the result of the south pole cooling down while the equator heated up. Jupiter may have compensated for the changes by forming new storms to help spread around the heat, the team said.

The UC Berkeley researchers are quick to note that the Great Red Spot, which has been raging for at least 340 years, is still a relatively stable storm that continues to crank out winds of up to 300 miles (480 kilometers) an hour.

“We find that the Red Spot has been shrinking but not slowing down,” Asay-Davis told SPACE.com.

But NASA researcher Glenn Orton, who wasn’t involved in the paper, says it’s possible the huge spot may one day disappear.

“It’s just a storm that, like many things, has a natural growth and disintegration rate,” Orton told CNN.

Asay-Davis and colleagues presented their work last November at a meeting of the American Physical Society, and it was recently submitted for publication in Icarus, the International Journal of Solar System Studies.

[Christine’s dad, this one’s for you.]


  1. jdellamore@stertil-koni.com
    June 20, 2009, 7:39 pm

    Victoria, thanks in part to the perspicacity of my daughter, I was very pleased to belatedly read your story on the Great Red Eye, which of course GAlileo first saw through one of his early telescopes.
    It’s sad to imagine that a 300+ year old storm might someday dissapear.
    Jean DellAmore