Thursday, July 23, 2009

Arctic Melt Rate Ahead of Last Year

Images (click to enlarge): 2009 Arctic sea ice extent through July 21 from National Snow and Ice Data Center; September 2009 sea ice outlook from Study of Environmental Arctic Change

The mid-July Arctic sea ice analysis shows that this season's melting is proceeding at a higher rate than last year, but less than the record year of 2007:
On July 21, Arctic sea ice extent was 8.28 million square kilometers (3.20 million square miles). This is 617,000 square kilometers (238,000 square miles) more ice than for the same day in 2007 and 1.36 million square kilometers (523,000 square miles) below the 1979 to 2000 average. Ice extent on July 21, 2009 remained 8.06% higher than the same day in 2007, yet was 2.44% below the same day in 2008 and 14.06% below the 1979-2000 average for that day.
The latest outlook from 16 individual estimates for the September seasonal minimum shows a range of levels from below the 2007 record to above the 2008 level:
The range of individual outlook values this month is from 4.0 to 5.2 million square kilometers, with most of the estimates in a narrow range of 4.4 to 5.2 million square kilometers. The two lowest estimates, 4.0 and 4.2 million square kilometers, would represent a new record minimum. All estimates are well below the 1979–2007 September climatological mean value of 6.7 million square kilometers. The uncertainty / error values, from those groups that provided them, are about 0.4 million square kilometers, thus many of the values essentially overlap.


susan said...

I'm hoping you might have have something to say about 2 and 3:
1. It's cold in Boston too, so
2. What's the connection between cold north Atlantic and extraordinary melt further north (I've seen the pix from Greenland, mostly from climatechangepsychology blog (Tenney Naumer)? I know it's not simple, just asking; maybe the answer is a couple of years down the road.
3. You mention squawk radio meteorologist in link from RealClimate in connection with one wmar who is a pest at DotEarth. For my sins, I've appointed myself (yeah, I should know better) as one who finds ways to reveal how phony his materials are. Do you know who he is (with, say, 90% certainty like the IPCC)? If so, I won't quote you, but would like to know.

CapitalClimate said...

So it was you who did that Google search for wmar :).
Interesting questions:
(2) If I understand you correctly, you're asking if Arctic melt could be correlated with the coolness in the Northeast. I haven't looked at Atlantic temperatures, so I don't know if they've been particularly cool. In any case, the cool weather is the result of a persistent circulation pattern at upper levels of the atmosphere which has a trough (low pressure) over the Great Lakes and Northeast. The counter-clockwise circulation around it brings in cooler air from the north, and the low pressure helps promote rain, which also keeps temperatures down. Here in the Mid Atlantic area, it's also somewhat cool, but also very dry. The pattern is very similar to one in the mid to late '60s which brought cool, droughty summers to the Mid Atlantic area. As I'm sure you've noticed, many other areas of the country have been having record heat, so the overall average has been near to above normal.
(3) I hate to give away a direct link, because it gives a site credibility points in Google, so I suggest you Google the following:
"wmar weather examiner".
Check out the global warming material and the dreck he links to (under "Interesting Weather Pages"), and I think you'll have found your boy. Good luck with DotEarth; the noise level drove me away some time ago.

CapitalClimate said...

P.S. After some further digging:
Check out who he links to in a comment at DotEarth.

Seasonal Outlook

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