Isudtyndingen af polarisen her i 2008.

..'New ice now covering the polar seas is not like older, thicker sea ice that once covered the region in winter, Rigor said. In 1989, 80 percent of the ice in the Arctic was at least 10 years old, he said. Today, only about 3 percent of the ice is that old.

New ice melts more quickly, and then open water absorbs more sunlight, warming the seas and making the fall freeze-up come even later, he said.

'Have we passed the tipping point?' he said. 'It's hard to see how the system may come back.'..

Spørgsmålet er nu mere hvad der skyldes smeltningen

Strong winds in Fram Strait in September of 2005 seem to have contributed to this summer's declining sea ice... the primary region where sea ice flows out of the Arctic Ocean and into the North Atlantic. ..especially strong winds during September 2005 appear to have "flushed" part of the older, thicker ice out of the Arctic. Hence, in spring of 2006, the melt season started with thinner ice, which is more apt to melt during the summer.

We can now confirm that August broke the pattern of unusually warm conditions that had characterized the Arctic from January through July 2006. Temperatures near the pole were actually slightly colder than average.. a pronounced average low-pressure area just off the pole..was especially strong.
Surface winds around the low-pressure system blow counterclockwise. The balance of forces on the ice, when the winds are blowing this way, promotes ice divergence. This spreads the ice over a larger area. Note that clockwise winds promote convergence, packing the existing ice into a smaller area.Air temperatures beneath such lows are typically colder than average.
The combination of cooler temperatures and counterclockwise winds helps explain the slower sea ice losses in August 2006 as compared to last year, when the central Arctic Ocean was not as stormy.

Taken together, the rapid sea ice losses that we've seen in June and July can partly be explained from the effects of this "triple whammy": it was warm; atmospheric circulation pushed ice away from the coast; and skies have been fairly clear.
However, what we are seeing also seems to reflect the "memory" of the ice to changes that have been occurring over the past couple of decades. In particular, there is mounting evidence of a shift from fairly thick ice to thinner ice, with this thinner ice more apt to completely melt out in summer.

at en ny rekord for mig at se ligner et "tipping point"/"point of no return"...

Arctic summer sea ice is unlikely to shrink drastically in 2008 beyond a record low set last year even though the long-term trend is a thaw tied to global warming...My feeling is that the situation will probably be the same as last year, or maybe a slight recovery
If we have two years in a row with a drastic drop in the ice extent at the end of the summer ... it would be a strong argument for having crossed a tipping point

Som baggrund til smelte sæsonen...

A panel of scientists from NSIDC and NASA will hold a media teleconference on Tuesday, March 18, at 10:00 a.m. Mountain Daylight Time (MDT). NSIDC will release full analysis of winter sea ice extent and conditions during the first week of April.

Science panelists at Tuesday's briefing will present the latest satellite observations of changing sea ice conditions in Earth's northern and southern polar regions.

Last September, sea ice levels reached record summertime lows in the Arctic, continuing a decades-long decline. This Last September, sea ice levels reached record summertime lows in the Arctic, continuing a decades-long decline.

This month, sea ice around Antarctica reaches its seasonal low point during the Southern Hemisphere summer and arctic sea ice hits its annual wintertime high.

Scientists are monitoring the amount and age of sea ice to see if the declining trend persists. Of particular interest is how arctic sea ice has been affected this winter by temperatures that are slightly colder than in recent years.

Kan det passé at der er tale om kl. 17:00 dansk tid?

-7:00 timer GMT: Mountain Time Zone (USA og Canada)

+1:00 time GMT: Amsterdam, Berlin, Bern Rom, Stockholm, Vienna, Belgrade, Budapest, Brussels, Madrid, Paris, Warsaw, Sarajvo, West Central Africa og Danmark

ja, bemærk hvor lidt af polarisen, som nu er flérårig

.. her noget mere om udtyndingen

The NASA scientists said that we'd need a string of cold years for the ice to fully recover.

"Arctic sea ice still on track for extreme melt" (3/6-08):

Vi er altså nu netop gået ind i solpletperiode nr. 24 på vej mod et forventet maksimum i 2012 eller 2013.

Solar Flux is 65
06/04/2008 by Kevin VE3EN at 21:50

The sun continues on its spotless streak and the solar flux has just hit the low of 65. This was also the same low we seen last year at this time in June 2007. So far during the current Cycle minimum we have not seen the number 64. How low will it go?