“Arctic Ice Volume Lowest Ever as Globe Warms: UN,” is how Reuters reported it today. Sorry I missed that in writing my earlier post on the 2008 report from the World Meteorological Organization (WMO), but it was buried deep in the press release (see below).
Note that the WMO is making a stronger statement than the National Snow and Ice Data Center (NSIDC) did in October (see NSIDC stunner: Arctic ice at “Likely Record-Low Volume”).
The NSIDC figure compares ice age in September 2007 (left) and September 2008 (right). It shows the sharp increase in thin first-year ice (red) and the decline in thick multi-year ice — both “second-year ice” (orange) and “third-year and older ice” (yellow). “White indicates areas of ice below ~50 percent, for which ice age cannot be determined.”
The WMO release says of the Arctic:
Arctic sea ice extent during the 2008 melt season dropped to its second-lowest level since satellite measurements began in 1979, reaching the lowest point in its annual cycle of melt and growth on 14 September 2008. Average sea ice extent over the month of September, a standard measure in the scientific study of Arctic sea ice, was 4.67 million km2. The record monthly low, set in 2007, was 4.3 million km2.
Because ice was thinner in 2008, overall ice volume was less than that in any other year.
A remarkable occurrence in 2008 was the dramatic disappearance of nearly one-quarter of the massive ancient ice shelves on Ellesmere Island. Ice 70 metres thick, which a century ago covered 9 000 km2, has been chiselled down to just 1 000 km2 today, underscoring the rapidity of changes taking place in the Arctic. The season strongly reinforces the 30-year downward trend in Artic sea ice extent.
The end of summer Arctic ice is nigh (see NSIDC: Arctic melt passes the point of no return, “We hate to say we told you so, but we did”).
Related Posts:
- First commercial ship sails through Northwest Passage: “I didn’t see one cube of ice”
- Despite cooler weather, Arctic ice retreat just misses last year’s mark
- NYT editors confused about Arctic warming
- Arctic shrinks by an Alaska and 3 Arizonas in August
- NSIDC: Arctic shortcuts open up; decline pace steady
- NSIDC: Arctic sea ice declines sharply in August
- What drove the dramatic retreat of arctic sea ice during summer 2007?
- Must See TV: Ice Ice Maybe (not)
Previous in TP Climate Progress
What are the radical changes to polar weather systems that we can expect from this change?
Once there was a way to get back homeward
Once there was a way to get back home
Boy, you’re gonna carry that weight
Carry that weight a long time
…yup, we’ve really got our work cut out for us this century, starting yesterday… godspeed.
Is there an albedo difference between older (thicker) ice and newer (thinner) ice?
A decrease in sea ice cover will lead to decreased albedo and cause the arctic to warm that much faster.
So are there any other effects of thin ice? Other than not being there during the summer.
Remember this?
Andy Revkin: “…the increasing summer retreats of sea ice, which many polar scientists say probably are being driven in part by global warming caused by humans, there will always be enough ice in certain parts of the Arctic to require icebreakers”.
Aaron d –
1) Thin ice is a symptom of Arctic warming.
2) thin ice melts sooner in the spring and summer, reducing albedo, thus increasing heat absorption by the ocean.
3) Albedo of old ice vs new ice? don’t know.
Albedo is basically reflection. Both new and old ice should be covered by the same new/older snow or soot/whatever.
But that’s just a guess….
What about the melting ice keeping the warming concealed somewhat?
We can calculate that 1 cubic kilometre ice warmed from -15 degrees Celcius to +15 C, and the energy extra demand just from ice to water makes 30 terawatthours which energy is out of the global warming.
Ice loss of Greenland, Antarctica and Alaska being some 1000 km3 per year makes 30 000 TWh out of global warming.
But the Arctic Sea loses ice ten times this much, making warming effect loss 300 000 TWh per year. The Arctic ice lost, this 300 000 TWh per year abruptly begins to warm the atmosphere. And the same effect later of course after the Greenland and Antarctic ice masses have gone.
David Lewis:
Even with AGW of 6C Arctic winters would remain cold enough for ice formation. But the day when the need for ice breakers in the Arctic becomes seasonal is probably not far away.
Hmmm, the latest articles I read indicate that Arctic ice has increased in the final months of 2008 to levels not seen since 1979. Now what is this article about, more B.S.
[JR: No such "articles" exist -- you have been duped.]
And why is Antarctic sea ice increasing?