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Post by radiant on Sept 20, 2009 23:33:13 GMT
the theory that melting the Arctic will lead to major warming of the sea water because of its exposure to the Sun is a theory and not a fact. The glancing angle of the Sun at that latitude suggests that little or no warming would be caused by such exposure. Another theory is that the best way to accelerate global cooling would be to remove as much sea ice from the Arctic as possible. I think that needs to be reworked a bit. In Southern and Arctic Finland in summer it gets very warm. All day sun even at a lower angle keeps warming the surface it touches. Interestingly though it was observed by the swedish explorer doing the north east passage that the Russian books describing the area were surprisingly detailed and seemed accurate as for example he said he could confirm that they were only getting two days of sun per month as described by the sources he had read. Also you have to consider that a warm sea without ice has the ability to radiate energy to space whereas a warm sea under a cold surface convection layer with ice on top of it cannot radiate to space and can only radiate to the relatively warmer freezing ice water layers above it. So ice has some ability to prevent heat loss that open water does not. Ie there is a temperature gradient via ice and ice water to space that act like a blanket that requires conduction thru it that would not be present if only the warm surface water was visibly exposed to space and only had to radiate the heat to space. The blanket being even more effective with snow on it Another point that might not be taken into consideration is that because water that is near freezing forms convection layers it could be that sun as you say coming at a low angle to the water does not penetrate the water as it would do and gets some kind of total internal reflection out of the water? But i would have thought that would be known and easily observed. Also clear new ice has pretty well no ability to reflect light. But snow covered ice is insulated from radiating to space. How can you model all of that? like you say plenty of theory but how much fact and known variability for different conditions rather than plenty of guesswork and opinion and promotion of commercial angles that promote production of rockets satellites radiometers books and careers
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ew3
New Member
Posts: 11
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Post by ew3 on Sept 21, 2009 0:02:16 GMT
Question -
Seems like it's rather difficult to compare year to year ice coverage since one side can pick the time of year to compare and the other will pick the time of year favorable to their opinion.
Perhaps a metric that is the integral (or Riemann sum) of the area would provide a better basis for comparison.
?
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Post by magellan on Sept 21, 2009 2:01:39 GMT
End of story.
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Post by neilhamp on Sept 21, 2009 10:20:28 GMT
At least NSIDC comments seem to have been accurate regarding the NE and NW passages: -
"Once again this year, the Northern Sea Route through the Arctic Ocean along the coast of Siberia opened. Although some ice remained in certain regions, two German ships managed to navigate the passage with Russian icebreaker escorts. Russian vessels have traversed the passage many times over the years, but as ice extent drops there is more interest from other nations. As in 2008, the shallow Amundsen's Northwest Passage briefly opened, but the deeper Parry's Channel of the Northwest Passage did not. In 2007, both channels were open."
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Post by dopeydog on Sept 22, 2009 11:28:51 GMT
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Post by icefisher on Sept 22, 2009 16:35:34 GMT
LOL! Of course Matt would say that the evil ice fairy is manufacturing thin first year ice while diabolically selectively melting only multi-year ice in order to fool the common man. ROTFLMAO!
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Post by douglavers on Sept 22, 2009 21:30:15 GMT
According to COI, Arctic temperatures have rocketed up over the last few days: ocean.dmi.dk/arctic/meant80n.uk.phpCould anyone explain how all the air North of the 80th parallel could suddenly rise by what appears to be about 7 degrees in the space of a few days? Looks like a mistake to me.
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Post by neilhamp on Sept 22, 2009 22:06:25 GMT
Not necessarily doug. Look back at previous years. There have been similar rises in the past
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Post by greenarrow on Sept 22, 2009 22:34:43 GMT
It has to do with the undulating pattern of the northern jet stream.
The larger the sub-arctic temperature halo grows the less variations you may see until a break in the jet stream occurs letting warmer air in from the south.
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Post by Ratty on Sept 22, 2009 23:05:10 GMT
I can't remember back to my high school science days ...
What happens to the atmosphere as sea ice freezes? Is there a latent heat factor that would warm the surrounding air?
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Post by tobyglyn on Sept 23, 2009 0:47:28 GMT
I can't remember back to my high school science days ... What happens to the atmosphere as sea ice freezes? Is there a latent heat factor that would warm the surrounding air? Harold Ambler (woodstove) posted this over at wuwt: The DMI Arctic temperature spike could be the release of latent heat during a “burst” of freezing. Clicking through the years, they appear often during the fall freeze-up. As Anthony indicates by mentioning the spike earlier this year (due, according to some, to the record sudden stratospheric warming in that case), the entire record is littered with such brief and sometimes dramatic rises.
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Post by radiant on Sept 23, 2009 5:22:37 GMT
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Post by Purinoli on Sept 23, 2009 7:29:20 GMT
I remember some nice experiments from physics during my study. We slowly cool a small beaker of extra pure water ( redistilled) untill it reached 0C. Temp even went lower to -0,2 C or so ( and still liquid!). Thus we obtained overcooled water. Than we just throw a coin into a beaker and all water vigorously freezed and on some parts it remelted due to localy accumulated latent heat and than all remained water slowly freezed when latent heat was overcomed by gradualy cooling...
Similar thing happened to me when I wanted to prepaire a very pure benzophenone ( melting point 47,6 C) by vacuum distillation/fractionation. In the receiver ( through water cooled heat exchange/condenser) I received a LIQUID pure benzophenone with the T around 25 C. At some moment this overcooled substance spontainously start freezing from the bottom up. All distillate become solid within few seconds. But the beaker became very hot ( around 40 C, about 15 C higher than before but still lower than melting point) due to released latent heat !
I think so this kind of situation can be seen in areas with sudden freezing water. I think so such events point to an intensive and sudden freezing process there arround.
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Post by douglavers on Sept 23, 2009 13:16:36 GMT
If Purinoli is right, we should see an extremely large gain in Arctic ice recorded over the next few days.
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Post by Pooh on Sept 23, 2009 15:03:56 GMT
Disinformation campaign?Greenland, Antarctic Ice 'in Runaway Melt Mode'Wednesday, September 23, 2009 Associated Press www.foxnews.com/story/0,2933,554123,00.html?test=latestnews "WASHINGTON — New satellite information shows that ice sheets in Greenland and western Antarctica continue to shrink faster than scientists thought and in some places are already in runaway melt mode."
Be careful with stories from Associated Press. Check them for source, accuracy and completeness. (The story appears to contribute to what Cass Sunstein calls the "Availability Heuristic", "making some risks seem especially likely to come to fruition whether or not they actually are".)1) This story does not differentiate Sea Ice from surface snow and ice. 2) Satellite measurements must be carefully calibrated. 3) No source is given for this story. 4) Melting sea ice does not raise sea levels. It floats. It has already displaced all the water it is going to displace. 5) "Arctic sea ice crossed over and exceeded the 2005 level on Sept 20." (minimum extent) noconsensus.wordpress.com/2009/09/6) The temperature of the West Antarctic was exaggerated by error in identification and location of some weather stations McIntyre, Steve. “Dirty Harry 4: When Harry Met Gill.” Blog. Climate Audit, February 2, 2009. www.climateaudit.org/?p=5054. ---. “West Antarctic Stations.” Climate Audit, February 1, 2009. www.climateaudit.org/?p=5044.
See Jeff Id's graph in Reply # 1727: noconsensus.files.wordpress.com/2009/09/untitled-1.jpg?w=330&h=484The horizontal green line is "Actual".
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