Sea Ice Extent

Sea ice extent is one of the more interesting barometers of climate change.

This year has been a record low, beating the previous record from 2007.  Extent is a little more than half the 1979-2000 median, or about 6 standard deviations below it.


From Justin Gillis's article today in the NYT:

“It’s hard even for people like me to believe, to see that climate change is actually doing what our worst fears dictated,” said Jennifer A. Francis, a Rutgers University scientist who studies the effect of sea ice on weather patterns. “It’s starting to give me chills, to tell you the truth.”....
....“It’s an example of how uncertainty is not our friend when it comes to climate-change risk,” said Michael E. Mann, a climate scientist at Pennsylvania State University. “In this case, the models were almost certainly too conservative in the changes they were projecting, probably because of important missing physics.”

Comments

  1. JamesAugust 28, 2012 at 6:58 AM

    I know a tiny bit about statistics. Something outside 2 SD is significant. Something outside 3 or 4 SD is unheard of...outside 6???!...why aren't there more people talking about this?

    ReplyDelete
  2. Michael RobertsAugust 29, 2012 at 3:16 AM

    Well, to be fair, the SD is estimated with a relatively small sample. Despite this, 6 SD is quite extreme. It would appear that, before long, sea ice will soon disappear during late summer.

    ReplyDelete

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