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Post by nautonnier on Jan 10, 2010 23:02:02 GMT
Jaxa is showing ice almost extending 2/3 or 3/4 of the way from Greenland to Iceland. Any idea if the ice has ever made it possible to walk across (in recent history)? You have to go to areas that are outside the normal reading of correctionists who seem to want to eliminate history of previous cold and warm periods. So you can get from an article on the spread of Malaria: "Climatologists regard the next 150 to 200 years the climax of the Little Ice Age. On average, temperatures were probably lower than in any similar episode since the end of the last major Ice Age[14].
The impact of this sudden change of climate was dramatic and global[1]. Glaciers advanced rapidly in Greenland, Iceland, Scandinavia, and the Alps. The Arctic pack ice extended so far south that there are six records of Eskimos landing their kayaks in Scotland. Large tracts of land, particularly at higher latitudes and altitudes, had to be abandoned. In many years, snowfall was much heavier than recorded before or since, and the snow lay on the ground for many months longer than it does today. Many springs and summers were outstandingly cold and wet, although there was great variability between years and groups of years. Crop practices throughout Europe had to be altered to adapt to the shortened, less reliable growing season, and there were many years of dearth and famine. Violent storms caused massive flooding and loss of life. Some of these resulted in permanent losses of large tracts of land from the Danish, German, and Dutch coasts. The dramatic cooling was captured in the paintings of the Flemish artist Pieter Bruegel (1525-1569), who initiated a new genre by completing at least seven winter landscapes in 2 years (Figure 2)."and for Steve - from the same article: "Climate changes were equally striking in other parts of the world. In Ethiopia and Mauritania, permanent snow was reported on mountain peaks at levels where it does not occur today. Timbuktu, an important city on the trans-Saharan caravan route, was flooded at least 13 times by the Niger River; there are no records of similar flooding before or since. In China, warm weather crops, such as oranges, were abandoned in Kiangsi Province, where they had been grown for centuries."www.medscape.com/viewarticle/414687_2There is an interesting chronology here from history not climatologists academic.emporia.edu/aberjame/ice/lec19/holocene.htm
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Post by hairball on Jan 10, 2010 23:49:54 GMT
I'd hate to be the Eskimo who arrives at a Scottish village in the middle of a severe famine.
Last time I posted here I said the negative AO would increase ice thickness vie the Beaufort gyre, but I guess the ice was rock hard already there before it arrived. I'm sure the milder one in October was discussed before I came here to annoy you all.
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Post by stranger on Jan 11, 2010 1:19:36 GMT
That's a good link, Nautonnier. While you are poking about, look at the works of the historic economists. They also have a great deal that is of interest to students of climatology. Especially those who specialize in mass migrations.
Hairball, long pork is better than no pork. Especially in a famine.
Stranger
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Post by hairball on Jan 11, 2010 2:47:18 GMT
I read back over the Arctic 2009 thread for when the AO went negative in October (I joined in the middle of November just before CRU had a whoopsie). You guys were "debating" the low ice growth at the time. Now, using the powers of ignorance and hubris, I will attempt to reveal what really happened! The Beaufort gyre must have been pretty hefty as you can see from the big circle compared to 2008: So I figure there was much more ice growth than normal (since there was so much open water trapped in the cold than usual when there's negative AO) all getting piled up where the clockwise current hit the existing ice. So I predict that there's a big mountain of ice right there that's gonna take quite some melting this Summer. It's now clear in my mind that the real damage to multi year ice was done during the early 90's and it'll take a lot to convince me carbon dioxide has anything to do with it.A couple of years with AO's as low as what we had around the new year during October and nobody will be talking about an ice-free Arctic any time this century. Sorry you have to read my guessing and if there's any truth to it I'm sure you've discussed it before. I wish I'd actually paid attention to AGW instead of just sighing when I had to read the propaganda in the paper. I'm trying to learn though. Was fun reading that thread back, climategate has really changed the conversation. (The AO looks like it might take another dip BTW)
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Post by aj1983 on Jan 11, 2010 11:54:14 GMT
Remember that the AO roughly only makes some regions colder and other regions warmer, as the amplitude of the Rossby waves increase. Increased mixing however will probably lead to a greater area below freezing, and stronger temperature fluctuations locally. Anyway, AO seems to be caused by a rise of the stratospheric temperature above the Arctic.
I'm wondering which natural processes cause this?
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Post by nautonnier on Jan 11, 2010 12:13:29 GMT
Remember that the AO roughly only makes some regions colder and other regions warmer, as the amplitude of the Rossby waves increase. Increased mixing however will probably lead to a greater area below freezing, and stronger temperature fluctuations locally. Anyway, AO seems to be caused by a rise of the stratospheric temperature above the Arctic. I'm wondering which natural processes cause this? AJ strange you should ask that.... "The significant fluctuation of ozone content under altitude h>20 km above sea level has been connected with the atmosphere dynamics, and particularly with the stratospheric warmings and with internal gravitational waves. The galactic cosmic rays (GCR) are considered as the main reason of the ionization of atmospheric gas constituents. " ieeexplore.ieee.org/Xplore/login.jsp?url=http://ieeexplore.ieee.org/iel5/9315/29615/01345807.pdf%3Farnumber%3D1345807&authDecision=-203"Correlation demonstrated between cosmic rays and temperature of the stratosphere"wattsupwiththat.com/2009/01/22/correlation-demonstrated-bewteen-cosmic-rays-and-temperature-of-the-stratosphere/Also interestingly I found this from : A Review of The Influence of Solar Changes on the Earths Climate by L. J. Gray1, J. D. Haigh2, R. G. Harrison1 of the Hadley Center " From these various indicators, there seems to be a general consensus on increases in solar activity during the twentieth century (Lockwood, 2001), but it is contentious (Lockwood, 1999; Cliver and Ling, 2002; Richardson et al, 2002) whether the changes occurred principally in the first half, or have continued through both halves. The reconstruction of Usoskin et al (2003) suggests that the period of high solar activity during the last 60 years could be unique in the past 1150 years. If confirmed, this may not, however, be a good indication of a high TSI, following the discussion in section 2.1. Solar changes cause changes in cosmic ray fluxes in the terrestrial atmosphere, by modulation through the heliospheric field (Lockwood, 2001). There is an inverse relation: at solar maximum, the atmospheric cosmic ray fluxes are reduced." meteo.lcd.lu/globalwarming/Gray/Influence_of_Solar_Changes_HCTN_62.pdf
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Post by aj1983 on Jan 11, 2010 12:31:50 GMT
So now the stratospheric heating variation is mainly caused by GCRs instead of UV? The first article is actually about the layer below the stratosphere, however it might be that changes in this layer (having greatest density and being closest to the troposphere) have the greatest influence on tropospheric circulation. From what I know SSW are induced from below (the troposphere), by dissipation of tropospheric waves (interaction of the Rossby waves by the QBO in an easterly phase), and not from above. Now I'm wondering why the NAO has become positive already just while solar activity was decreasing, and was negative when solar activity peaked. Thanks for the links, especially the latter is interesting. I've read more sources which tend to show some correlation with solar activity (although correlation is not causation), and cold winters seem to be somewhat clustered around solar minima. Probably more things are involved.
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Post by icefisher on Jan 11, 2010 16:43:00 GMT
So now the stratospheric heating variation is mainly caused by GCRs instead of UV? If caused by CO2 it would be essentially an identical mechanism. So the answer I think would be yes. . . .assuming of course either have anything to do with it.
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Post by hairball on Jan 11, 2010 20:00:25 GMT
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Post by kiwistonewall on Jan 11, 2010 21:26:29 GMT
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Post by slh1234 on Jan 12, 2010 3:49:17 GMT
This poor commentor on that article just fits the stereotypes too well. But here it is in his own words: With that as a basic tenet, is there any wonder they are so easily led?
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Post by graywolf on Jan 14, 2010 0:47:25 GMT
Of course the Arctic Gyre, via the Arctic current, could just be flushing out berg after berg along the East Greenland coast (as has happened this past 7 years).
We should track down a nice infra red/microwave sat. image now shouldn't we?
Come late Feb we'll be able to get the odd glimpse on visible (ESP. if it's so far south?) now shouldn't we?
Let me think?
Wasn't the remainder of the 'old perennial' stacked up behind Svalbard before it got dark?
Hasn't it been rather warm up there (comparatively ) recently?
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Post by hunter on Jan 14, 2010 13:33:48 GMT
graywolf shows us what AGW true believers are reduced to: hoping that something, anything, really soon, shows s that the apocalypse is still under way.
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Post by hairball on Jan 14, 2010 14:56:26 GMT
Not this year graywolf. The gyre's back spinning clockwise like before '89 and faster than in a long time thanks to all that open water. Unluckily for the poor cod it doesn't seem to be letting them have much cold water down south. Looks like there'll be a big lump of new perennial taking the scenic route to Svalbard and most likely 2 more on the way by the time it gets there. Chin up though, I hear the fish are getting osteoporosis and the polar bears are cannibalising their young now.
Oh, and all that heat up there? It's coming off the water as it freezes in massive quantities and heading out into deep space.
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Post by kiwistonewall on Jan 15, 2010 11:23:49 GMT
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