okie333 Posted November 23, 2011 Share Posted November 23, 2011 At first I thought that chart was global and that the world was ending. Sounds like a good argument HM, I hope you are right. No, here's the full Northern Hemisphere graph: Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted November 24, 2011 Share Posted November 24, 2011 Anyone jumping off the cold forecasts for mid-winter will regret it. Okay okay...I'm being a dbag. But the build up of snow cover and ozone is enough evidence to me, along with the active MJO, to suggest the AO is heading into the tank at some point--solar notwithstanding. Can the arctic torching have any affect good or bad? I hope your right. November in my neck of the woods is running about 6.5f above the long term normal(53.6F) and is progged to finish November around 53-53.5F mean temp. November long term mean Is 45.6 here. The record is 54.6f so this is very close. It would be nice to get some decent cOld and snow Link to comment Share on other sites More sharing options...
usedtobe Posted November 24, 2011 Share Posted November 24, 2011 Anyone jumping off the cold forecasts for mid-winter will regret it. Okay okay...I'm being a dbag. But the build up of snow cover and ozone is enough evidence to me, along with the active MJO, to suggest the AO is heading into the tank at some point--solar notwithstanding. I think the question is when. There's a delay between snow cover and the development of a negative ao plus we have to wait for the mjo to get past the dreaded 4-6 phases. My guess now if sometime in Jan but think there will be a positive PNA to bring down some arctic air before then, probably starting in the west like the euro is doing but it may still be too fast. Link to comment Share on other sites More sharing options...
griteater Posted December 7, 2011 Share Posted December 7, 2011 It's early, but this analysis has been rock solid thus far... I found another stratospheric temperature data set that goes back to 1950. This time I focused on the area 50-90N 90E-150W (basically Russia and surrounding areas) where the correlation is strongest. I used 70mb stratospheric temps from the NCEP reanalysis: http://www.esrl.noaa.../timeseries1.pl Based on this I would give us at least a 75% chance of having a +AO in December+January. If the stratosphere remains near record cold for the next 2-3 weeks, our chances diminish even further. There has never been a significantly -AO January following a top 10 cold stratosphere. November stratosphere -The December AO was 1.09 higher following the 10 coldest than the 10 warmest. -The January AO was 1.75 higher following the 10 coldest than the 10 warmest. -The December AO was .63 higher following cooler than average than warmer than average -The January AO was 1.71 higher following cooler than average than warmer than average November + December stratosphere -The December AO was 1.82 higher following the 10 coldest than the 10 warmest -The January AO was 2.81 higher following the 10 coldest than the 10 warmest -The December AO was .72 higher following cooler than average than warmer than average -The January AO was 1.41 higher following cooler than average than warmer than average - 8/10 coldest had +AO Dec, only 1 below -.1 - 8/10 coldest had +AO Jan, none below -.2 -9/10 warmest had -AO Dec, none above +.2 -9/10 warmest had -AO Jan, none above +.3 For reference this is what this Oct 15 - Nov 15 looked like this year: Which matches very well to the November stratosphere preceding +AOs. The following is a correlation between the November stratosphere temperature and the subsequent January AO. In addition, if we look higher in the stratosphere at 20mb the spatial pattern of anomalies 10/15-11/15 has matched that of other Novembers preceding +AO December and Januaries. The similarity is astonishing. The current stratosphere is in a classic "pre +AO pattern." 10/15-11/15 20mb temps this year: November 20mb temp correlation to subsequent AO: Link to comment Share on other sites More sharing options...
SeanVA Posted December 9, 2011 Share Posted December 9, 2011 Looks like sea ice is doing a lot better this winter than last but snow cover over in the US isn't the best and in Europe it is terrible. Link to comment Share on other sites More sharing options...
LithiaWx Posted December 9, 2011 Share Posted December 9, 2011 Looks like sea ice is doing a lot better this winter than last but snow cover over in the US isn't the best and in Europe it is terrible. cue the arctic is torching and the ice is not doing better crowd in 3...2...1... Link to comment Share on other sites More sharing options...
Bob Chill Posted December 9, 2011 Share Posted December 9, 2011 Looks like sea ice is doing a lot better this winter than last but snow cover over in the US isn't the best and in Europe it is terrible. It's been cold as crap in AK so far. This season of Deadliest Catch should be fun. Lotsa storms and super cold weather. Doesn't look to change in Decemeber. Bering Sea might be pretty frozen by the end of the month. Link to comment Share on other sites More sharing options...
BethesdaWX Posted December 9, 2011 Share Posted December 9, 2011 cue the arctic is torching and the ice is not doing better crowd in 3...2...1... Comparing it to last winter isn't saying much dude, the arctic is definitely torching relative to past decades, which is to be expected given decreased albedo and increased heat intake to the oceans during the summer when it matters. There are those who claim faster heat release with less summer ice heading into fall, but really that's heat that would never have gotten into the waters in the first place with more ice, and one faster rebounds are natural with more area left to freeze over relative to the temperature profile. Believe it or not the arctic warming seen on it's own isn't enough to cause significant melting on its own in the arctic fall or winter, the temp up there is still easily cold enough to freeze it all no contest then. Its the loss of multi-year thick ice which has the albedo/energy shield effect in the summer. Less thick ice means more summer melt, and an ice pack vulnerable to damage from storms. That resulted from the beaufort gyre current weakening, allowing for the ice to flush out during storms rather than being held in place. Thinner ice to start, then adding in its not being held in place, is a death sentence to the icepack. Evidence for this is in the UAH satellite record, the arctic cooled slightly from 1979 to 1994 before warming rapidly, the AMO does seem to correlate to the BG current strength which began dying slowly in the late 1980s especially in the last decade, until the 2008/09 period, which is when it bottomed out. It is easily cold enough up there to re-freeze and build albedo but the AMO needs to recover first, imo. It's like the bozoes claiming ice loss on the heart of the Antarctic ice sheet where it's always well below freezing, at least in much of the area. Ice can't melt when the temp is well below freezing 24/7. It can transevaporate, but that's not temp induced. That'd be cloud induced. Link to comment Share on other sites More sharing options...
Riptide Posted December 9, 2011 Share Posted December 9, 2011 The positive AO regime has played a big role in the growth of ice and snow cover this year. There is this idea that a +AO is always detrimental for winter temperatures, leading to positive anomalies in the mid-laditudes. Mabye some mets would agree that a +AO regime is necessary to build significant arctic air that may leave the polar regions in the future. Link to comment Share on other sites More sharing options...
tacoman25 Posted December 9, 2011 Share Posted December 9, 2011 The positive AO regime has played a big role in the growth of ice and snow cover this year. There is this idea that a +AO is always detrimental for winter temperatures, leading to positive anomalies in the mid-laditudes. Mabye some mets would agree that a +AO regime is necessary to build significant arctic air that may leave the polar regions in the future. 1978-79, the coldest U.S. winter on record, was preceded by a very +AO fall I believe. Link to comment Share on other sites More sharing options...
okie333 Posted December 9, 2011 Share Posted December 9, 2011 1978-79, the coldest U.S. winter on record, was preceded by a very +AO fall I believe. Link to comment Share on other sites More sharing options...
BethesdaWX Posted December 9, 2011 Share Posted December 9, 2011 The positive AO regime has played a big role in the growth of ice and snow cover this year. There is this idea that a +AO is always detrimental for winter temperatures, leading to positive anomalies in the mid-laditudes. Mabye some mets would agree that a +AO regime is necessary to build significant arctic air that may leave the polar regions in the future. http://www.cpc.ncep.noaa.gov/products//CWlink/daily_ao_index/ao.sprd2.gif[/ When it is positive it usually is detrimental, to more than just mid latitude temperatures, but global cloud albedo, if more albedo is a preference. Link to comment Share on other sites More sharing options...
BethesdaWX Posted December 9, 2011 Share Posted December 9, 2011 What is this intended to convey? Link to comment Share on other sites More sharing options...
okie333 Posted December 9, 2011 Share Posted December 9, 2011 What is this intended to convey? Scandinavian ridge, weak Eastern US ridge, Greenland trough, Russia trough, Far East ridge... not too many differences except in Alaska. Link to comment Share on other sites More sharing options...
BethesdaWX Posted December 9, 2011 Share Posted December 9, 2011 Scandinavian ridge, weak Eastern US ridge, Greenland trough, Russia trough, Far East ridge... not too many differences except in Alaska. I know, I'm just curious what you think that means in relation to now and the near future. Link to comment Share on other sites More sharing options...
okie333 Posted December 9, 2011 Share Posted December 9, 2011 I know, I'm just curious what you think that means in relation to now and the near future. It means there's probably going to be at least a minor SSW around Christmas, and that "epic warmth" is just not going to happen even before then (EPO is too strongly entrenched). There could even be a McFarland sig while we're waiting for the AO to go down, after the SSW. Major Arctic outbreak possible for New Year's in much of the nation, coupled with two (or three) very powerful jet streams. IMO the AO is just going to "lock it in"... a cross-polar flow scenario (-EPO +NAO both near the pole) will actually bring the air to the USA. When the PV is displaced southward (and into the US/Canada... really there's not much chance of it being Asia instead), a -NAO will come in from the southeastward direction to replace the Greenland vortex. This will turn into a -AO over time, and once that happens the EPO will be an afterthought (though I don't expect it to change much... it may retrogress to a -WPO by then [don't hold your breath though, PNW users], but that doesn't really matter much since its only job for areas east of the Rockies is to bring cold air south, and by that time it will already be there) Link to comment Share on other sites More sharing options...
Big O Posted December 9, 2011 Share Posted December 9, 2011 It means there's probably going to be at least a minor SSW around Christmas, and that "epic warmth" is just not going to happen even before then (EPO is too strongly entrenched). There could even be a McFarland sig while we're waiting for the AO to go down, after the SSW. Major Arctic outbreak possible for New Year's in much of the nation, coupled with two (or three) very powerful jet streams. IMO the AO is just going to "lock it in"... a cross-polar flow scenario (-EPO +NAO both near the pole) will actually bring the air to the USA. When the PV is displaced southward (and into the US/Canada... really there's not much chance of it being Asia instead), a -NAO will come in from the southeastward direction to replace the Greenland vortex. This will turn into a -AO over time, and once that happens the EPO will be an afterthought (though I don't expect it to change much... it may retrogress to a -WPO by then [don't hold your breath though, PNW users], but that doesn't really matter much since its only job for areas east of the Rockies is to bring cold air south, and by that time it will already be there) What are you seeing that is causing you to make these pretty bold conclusions? Link to comment Share on other sites More sharing options...
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