Hi Torsten,

It is generally accepted that the Arctic is warming relative to the rest of the world, in a process known as Arctic amplification.  Recent research suggests that, as a consequence, the jet stream pattern is less geographically constrained but slower moving, leading to extremes of hot and cold, wet and dry [1].  Also the NH Hadley and Ferrel cells will have expanded with their boundaries moving northwards [2abc].

I would assume the Arctic warming has thus affected the monsoons, to make them less predictable with more frequent extremes.  Can anybody vouch for this?

BTW, I've come across another factor in Arctic amplification, which is the extra IR absorption by CO2 at the pole [3].  This paper, from 2008 I would guess, gives a prediction of sea-ice-free September 2013!

Cheers,

John

P.S.  Tietsche has done a grave disservice by suggesting the sea ice will recover by itself, and it hasn't reached a tipping point [4].  But Tim Lenton, self-proclaimed expert on tipping points, now admits that the sea ice may have already passed a crucial tipping point [5].

[1] http://www.climatecentral.org/news/arctic-warming-is-altering-weather-patterns-study-shows/
 
"The study contains a stark warning about future weather patterns, given projections showing that Arctic climate change is likely to accelerate in coming years. “As the Arctic sea ice cover continues to disappear and the snow cover melts ever earlier over vast regions of Eurasia and North America, it is expected that large-scale circulation patterns throughout the northern hemisphere will become increasingly influenced by Arctic amplification,” the study reports."

[2a] http://www.scientificamerican.com/article.cfm?id=whats-causing-dry-winter
[2b] http://www.thescienceforum.com/environmental-issues/27700-global-warming-effects.html
[2c] http://ossfoundation.us/projects/environment/global-warming/latitudinal-shift

[3] http://mb-soft.com/public3/globalze.html

[4] http://www.wunderground.com/blog/RickyRood/comment.html?entrynum=191

"Another study that is of interest is the paper in Geophysical Research Letters, Recovery mechanisms of Arctic summer sea ice, by S. Tietsche and colleagues. This is a model study. With a model the scientist owns the world and can prescribe what it looks like. In these numerical experiments, the Arctic is prescribed with no ice. Then whether or not the ice recovers is explored. In these studies the ice does recover. The ocean does indeed take up extra heat in the summer, but it gives it up quickly in the fall. This is followed by the formation of first year ice in the winter. The ice-albedo feedback that might let the ice melt runaway is limited. Tietsche et al. conclude that it is not likely that Arctic sea ice will reach a tipping point this century."

[5] http://www.newscientist.com/article/dn21626-arctic-sea-ice-may-have-passed-crucial-tipping-point.html

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On 13/04/2012 11:42, Torsten Mark Kowal wrote:
[log in to unmask]" type="cite">
Forumers:
We all know that weather isn't climate, but take a look at this...... These events do happen, but very rarely.
Key to this one was that "precipitable water values were 3 standard deviations above the norm for this time of year."...
"Weather weirding" ..... http://www.nytimes.com/2012/03/29/science/earth/arctic-sea-ice-eyed-for-clues-to-weather-extremes.html