View Full Version : arctic sea ice revisit


iceaura
06-30-08, 04:08 AM
Not too long ago, IIRC, we were informed that this past winter the arctic sea ice had so far recovered from its record low in 2007 as to wipe out all the global warming from 1998. Things were back to normal, and Al Gore had been proved wrong about something or another again,

That was bogus, of course - for one thing, only extent and particular thickness were involved, and not average thickness or density; for another, one cold winter doth not a cooling trend make - but repetition of bogus stuff tends to have a residual effect. So a revisit to the Arctic sea ice situation:

http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=06&fd=25&fy=2007&sm=06&sd=25&sy=2008 We still have a little more ice than we did last year. Somebody said the researchers were taking bets on whether the North Pole would go ice free again, and the odds were running 50/50.

Comparing the very warmest year, the one we are supposed to have completely recovered from, we see that even after this cold winter we are still missing a lot of ice:
http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=06&fd=25&fy=1998&sm=06&sd=25&sy=2008

Andre
07-01-08, 04:26 PM
No it still was bogus. The extent of the sea ice has nothing to do with global warming:

The unusual large arctic melt of 2007 was attributed to unusual winds:

http://www.nasa.gov/vision/earth/lookingatearth/quikscat-20071001.html

... Nghiem said the rapid decline in winter perennial ice the past two years was caused by unusual winds. "Unusual atmospheric conditions set up wind patterns that compressed the sea ice, loaded it into the Transpolar Drift Stream and then sped its flow out of the Arctic," he said. When that sea ice reached lower latitudes, it rapidly melted in the warmer waters.

"The winds causing this trend in ice reduction were set up by an unusual pattern of atmospheric pressure that began at the beginning of this century," Nghiem said.....

Enmos
07-01-08, 06:38 PM
Where did the unusual patterns of atmospheric pressure come from ?

Enmos
07-01-08, 06:47 PM
When one looks at the wintertime pattern of the Arctic Oscillation (AO) over the past 100 years, a mostly random pattern of positive and negative AO modes is apparent (Figure 6). However, one anomalous period is very striking: a string of seven consecutive years with a positive AO, including two years (1989 and 1990) with the highest AO index ever observed. During this period, strong westerly winds rapidly flushed more than 80% of the oldest, thickest sea ice out of the Arctic Ocean, leaving most of the Arctic covered with ice less than three years old (Figure 7). Younger ice is much thinner, and melts much more readily. Rigor and Wallace (2004) estimate that at least half of the loss of sea ice in the Arctic since 1979 is due to these six years of strange weather with very low surface pressure over the Arctic. Did climate change cause this unusual pattern between 1989 and 1995? It is possible, but no one has published any papers showing how this might have occurred. For now, the assumption is that this major loss of Arctic sea ice due to wind patterns between 1989-1995 is natural.

Since the strange positive Arctic Oscillation years of 1989-1995, a number of years with negative AO have occurred. Normally, during negative AO years, ice extent and thickness increase in the Arctic. But instead, ice extent and thickness during these periods has continued to decline.

The monthly AO index also exhibited mostly positive values during September to November 2005 and March 2006 to March 2007, enhancing ice transport out of the Arctic. In September 2005, a pronounced atmospheric low pressure over the Barents Sea, in concert with a strong high pressure over the Canadian Basin, set up unusually strong northerly winds over Fram Strait, pushing ice more than a year old (perennial ice) that had accumulated north of Greenland out of the Arctic like a runaway train. Between March 2005 and March 2007, the amount of perennial ice fell by 23% (Nghiem et al., 2007), and perennial ice in the Arctic is now half of what it was in the 1950s. Seasonal ice (ice that is less than a year old), is thinner, more easily compressed, and can be pushed by wind out of the Arctic much more readily. It also melts more readily, since it is thinner. When an unusually strong high pressure system settled over the North Pole during the summer of 2007, the lower than average cloud cover that resulted allowed the sun to drastically melt the relatively thin ice that decades of gradual melting had created. The ice will re-freeze in winter, but this new seasonal ice reflects less sunlight than perennial ice. When summer returns, this will lead to even warmer temperatures in the Arctic. It is difficult to see how the Arctic will recover from 2007's drastic loss of sea ice, and an ice-free Arctic in summertime is possible by 2013, according to Arctic research scientist Dr. Wieslaw Maslowski of the Naval Postgraduate School in Monterey, California.

http://icons-pe.wxug.com/data/climate_images/ao.gif

http://www.wunderground.com/climate/SeaIce.asp

iceaura
07-01-08, 09:16 PM
No it still was bogus. The extent of the sea ice has nothing to do with global warming:

The unusual large arctic melt of 2007 was attributed to unusual winds: So my point-

which was that the posts and entire threads on this forum advancing the increased ice cover of 2008 as evidence against global warming, were bogus

is well taken - agreed ?

Andre
07-06-08, 01:50 AM
So my point-

which was that the posts and entire threads on this forum about reduced ice cover of 2006 and 2007 as evidence for global warming, were bogus

is well taken - agreed ?

iceaura
07-06-08, 08:45 PM
So my point-

which was that the posts and entire threads on this forum about reduced ice cover of 2006 and 2007 as evidence for global warming, were bogus

is well taken - agreed ? No. They were part of a trend - a trend is evidence.

Foxus
07-07-08, 02:17 AM
This global warming hype needs to stop. One year they say it's going to happen in 100 years and the next they say it's going to happen tomorrow! IMO i think a majority of these claims are to help the emerging "green" market. Granted the "green" market has a pretty good stand already, but it has changed nothing.

Andre
07-07-08, 08:46 AM
They were part of a trend - a trend is evidence.

Exactly:

http://www.nasa.gov/vision/earth/lookingatearth/quikscat-20071001.html

"The winds causing this trend in ice reduction were set up by an unusual pattern of atmospheric pressure that began at the beginning of this century," Nghiem said.

Cazzo
07-09-08, 10:09 PM
Just a couple months ago they found all those volcanos under the Arctic :
http://www.canada.com/topics/news/story.html?id=81bb2fd3-63f1-476f-b0be-f48c0dc90304

Now if those volcanos were coal plants instead (yea I know that's not possible, but lets say they were), you could bet $100 the "human caused" global warming "experts" would have been instantly forming additional links between those coal plants and the melting arctic ice.
BUT, since it's natural, the volcanos, of course these "experts" won't make any links....:rolleyes:

I'm not saying I think the volcanos "are" the cause, but my statement's probably true.

iceaura
07-09-08, 10:24 PM
BUT, since it's natural, the volcanos, of course these "experts" have won't make any links... If you read your link, the possibility was considered - it just didn't check out.

Cazzo
07-09-08, 10:36 PM
If you read your link, the possibility was considered - it just didn't check out.

Of course not, because the volcanos don't involve people.

iceaura
07-09-08, 11:04 PM
Of course not, because the volcanos don't involve people. Was that why ? The guy in charge of the research program seemed to say otherwise.

Or do we need to add yet another branch of science and hundreds of researchers to the great Al Gore conspiracy ?

Vkothii
07-10-08, 02:53 AM
One year they say it's going to happen in 100 years and the next they say it's going to happen tomorrow! Someone needs to read the sub-clause.
It's happening today - it was happening thirty years ago too, maybe a century or so before then.

Who knows, we humans may have postponed the onset of the next glaciation indefinitely starting thousands of years ago.
It's happening in a hundred years for sure, and the next hundred after that too.