The climate is changing: the Arctic Dipole emerges
The dramatic loss of Arctic sea ice in recent years has created a fundamental new change in the atmospheric circulation in the Northern Hemisphere that has sped up sea ice loss and is affecting fall and winter weather across most of the Northern Hemisphere, according to several recent studies. Arctic sea ice loss peaks in September and October, exposing a large area of open water that heats the air above it. This extra heat has helped drive September - November air temperatures in the Arctic to 1°C (1.8°F) or more above average over about half of the depth of the lower atmosphere (Figure 1). This deep layer of warm air has grown less dense and expanded, pushing the top of the troposphere (the lower atmosphere) higher. The result has been a decrease in the pressure gradient (the difference in pressure) between the North Pole and mid-latitudes. With not as much difference in pressure to try and equalize, the jet stream has slowed down in the Arctic, creating a major change in the atmospheric circulation for the Northern Hemisphere.
Figure 1. Cross section of Arctic temperature anomaly from 1000 mb (the surface) to 300 mb (roughly, the height of the top of the lower atmosphere or troposphere). Cross section is taken along the Date Line (180°W), from 60°N latitude (left side) to the North Pole (right side), for September - November for the 12-year period 1998 - 2009. Three year averages were done to reduce the amount of year-to-year noise associated with natural variation. Other cross sections along different lines of longitude show similar results, though typically with more warming aloft and less warming at the surface. Image credit: NOAA/ESRL.
A new atmospheric pattern emerges: the Arctic Dipole
In a 2008 article titled, Recent radical shifts of atmospheric circulations and rapid changes in Arctic climate system Zhang et al. show that the extreme loss of Arctic sea ice since 2001 has been accompanied by a radical shift of the Arctic atmospheric circulation patterns, into a new mode they call the Arctic Rapid change Pattern. The new atmospheric circulation pattern has also been recognized by other researchers, who refer to it as the Arctic Dipole (Richter-Menge et al., 2009). The old atmospheric patterns that controlled Arctic weather--the North Atlantic Oscillation (NAO) and Arctic Oscillation (AO), which featured air flow that tended to circle the pole, now alternate with the new Arctic Dipole pattern. The Arctic Dipole pattern features anomalous high pressure on the North American side of the Arctic, and low pressure on the Eurasian side. This results in winds blowing more from south to north, increasing transport of heat into the central Arctic Ocean. The Arctic Dipole pattern occurred in all summer months of 2007 and helped support the record 2007 summer reduction in sea ice extent (Overland et al., 2008). Overland et al., 2010 also found that the Arctic Dipole pattern tended to create an increase in easterly winds in the lower half of the atmosphere of 40% in fall, between 2002 - 2008. Fall 2008 through spring 2009 featured the old AO pattern. The new Arctic Dipole pattern re-appeared in June - July 2009, but the old AO pattern dominated in August - September, resulting in greater sea ice extent than in 2007 and 2008. The Arctic Dipole pattern was active again in October, inactive in November, and reasserted itself this December. As a result, Arctic sea ice reached a new record minimum for a 10-day period in early November, increased above record lows during late November and early December, and appears poised again to reach a new record minimum later this December (Figure 2).
Figure 2. Sea ice extent in the Arctic for this year (blue line) compared to the record low year of 2007 (green line) and 1979 - 2000 average (gray line). One could make the ice loss looks less significant by using the full satellite data record from 1979 - 2008 for the average. Image credit: National Snow and Ice Data Center.
Arctic Dipole blamed for colder winters in East Asia
It turns out that the new Arctic circulation patterns help to intensify the Siberian High, a large semi-permanent region of surface high pressure prevalent in winter over Siberia. According to Honda et al. (2009), this results in increased flow of cold air out of the Arctic in early winter over eastern Russia, Japan, Korea, and eastern China, causing colder temperatures. By late winter, the pattern shifts, resulting in colder than average temperatures from East Asia to Europe.
Arctic Dipole blamed for drier winters in Northern Europe
Francis et al. (2009) found that during 1979 - 2006, years that had unusually low summertime Arctic sea had a 10 - 20% reduction in the temperature difference between the Equator and North Pole. This resulted in a weaker jet stream with slower winds that lasted a full six months, through fall and winter. The weaker jet caused a weaker Aleutian Low and Icelandic Low during the winter, resulting in a more negative North Atlantic Oscillation--a pattern that usually brings reduced winter precipitation over Alaska and Northern Europe and increased precipitation over Southern Europe. A more negative NAO also tends to bring cold winters to eastern North America and Europe. Though it was not mentioned in the article, reduced Arctic sea ice may also cause dry early winter conditions in the U.S. and the Caribbean (Figure 3). The authors noted that strong La Niña or El Niño events can have a much larger influence on the wintertime atmospheric circulation, which will overshadow the changes due to Arctic sea ice loss.
Figure 3. Difference in early winter precipitation (November - January) between five years that had low Arctic sea ice (2005, 2006, 2007, 2008, and 2009), and five years that had unusually high Arctic sea ice extent (1981, 1984, 1986, 1989, 1993). Note that low sea ice may be responsible for dry conditions in early winter for the Caribbean and most of the U.S.
Commentary
Arctic sea ice loss appears to have created a new atmospheric circulation pattern that brings more warm air in the Arctic, creating a positive feedback loop that causes even more sea ice loss. This feedback loop increases the likelihood that an ice-free Arctic in the summer will indeed come by 2030, as many Arctic experts are predicting. It's worth noting that such an atmospheric circulation shift was not predicted by the climate models. Indeed, the loss of Arctic sea ice over the past three years exceeds what any of our models were predicting (Figure 4). While we can rightly criticize these models for their inaccuracy, we should realize that they are just as capable of making errors not in our favor as they are of making errors in our favor.
Figure 4. Arctic sea ice extent from observations (thick orange line) and 13 model forecasts used to formulate the 2007 IPCC report (light lines). The thick black line is the multi-model ensemble mean, with the standard deviation plotted as a dashed black line. Image has been updated to include the observed 2008 and 2009 measurements. None of the models predicted the record 2007 sea ice loss. Image credit: Arctic sea ice decline: Faster than forecast by Stroeve et al., 2007.
References
Francis, J.A., W. Chan, D.J. Leathers, J.R. Miller, and D.E. Veron, 2009, "Winter Northern Hemisphere weather patterns remember summer Arctic sea-ice extent", Geophysical Research Letters, 36, L07503, doi:10.1029/2009GL037274.
Honda, M., J. Inoue, and S. Yamane, 2009. Influence of low Arctic sea - ice minima on anomalously cold Eurasian winters, Geophys. Res. Lett., 36, L08707, doi:10.1029/2008GL037079.
Overland, J. E., M. Wang, and S. Salo, 2008: The recent Arctic warm period, Tellus, 60A, 589.597.
Overland, J. E., and M. Wang, 2010: Large-scale atmospheric circulation changes associated with the recent loss of Arctic sea ice. Tellus, 62A, 1–9.
Richter-Menge, J., and J.E. Overland, Eds., 2009: Arctic Report Card 2009, http://www.arctic.noaa.gov/reportcard.
Simmonds, I., and K. Keay (2009), Extraordinary September Arctic sea ice reductions and their relationships with storm behavior over 1979.2008, Geophys. Res. Lett., 36, L19715, doi:10.1029/2009GL039810.
Wu, B., J. Wang, and J. E. Walsh, 2006: Dipole anomaly in the winter Arctic atmosphere and its association with sea ice motion. J. Climate, 19, 210-225.
Zhang, X., A. Sorteberg, J. Zhang, R. Gerdes, and J. C. Comiso (2008), Recent radical shifts of atmospheric circulations and rapid changes in Arctic climate system, Geophys. Res. Lett., 35, L22701, doi:10.1029/2008GL035607.
Jeff Masters
Reader Comments
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Any snow/Ice event is significant down here in the south...LOL
How far south does that snow go?
Hey now! P'cola wants in on this!!
Ike and BF 2 WU bloggers
Sarasota a city in Fl...LOL
I know Ike, who is BF? The Ice/snow event will affect S La, S Ms, S Cental Al and the Western Fl Panhandle, according the the GFS 00Z 12-23-09 runs..
An interesting note on the NCEP products past 7 days, I from NOAA:
Statement on the Use of GFS Output Beyond Day 7
There is some concern about NCEP model variability from run to run, particularly at extended ranges beyond 7-8 days. The American Meteorological Society Statement adopted on January 14, 2001, titled "Statement on Seasonal to Interannual Climate Prediction" (Bull. Amer. Met. Soc., 82, 701), states, in part, the limit of predictability for day-to-day weather changes for deterministic forecasts is "in the range of 1-2 weeks." NCEP agrees with this statement and notes that for current state-of-the-art models, the limit of "useful skill" is about 7-8 days. Beyond that range, deterministic numerical weather predictions are characterized by little or no skill and suffer from large run to run variability. However, ensemble or probability forecasts may offer improved predictive skill
Ready-AIM-Fire just for the buyer
All the way past my driveway :)
I have no idea actually.. but I would assume all the way down into Puget Sound.
That yellow thing, some call the "SUN" is finally peeking out of the clouds, for the 1st time since Thursday!!
(Chuckle) G'morning, Auby,
I could swear he fixed that sentence before my eyes...maybe I'm the one who needs more java! So, will you still "melt" if you go outside?
Pink is 10 inches + in the last 14 days:
any suggestions for a name for my blog?
Other than "Thank G-d She's Off the Main Blog!"
Cheap Thrills
BF.. BeachFoxx.. lives in Destin FL
Sarasota = City in Florida = Surfmom lives close by
No rain is gone and its in the 60s here today....LOL
FANTASTIC! Many thanks; I would NEVER have come up with something so clever! What a great blog.
Dallas-Ft Worth, TX looks like we're gonna get slapped with snow 2 days before Christmas:
The newest GFS run shows a lil' freezing rain on 12-23. Now looks like a rain event for us!!
You Dawg! Yeah, I'm Cheap, but I ain't easy (to live with, ask my husband...no please don't.)
Nope....
Try this link
Its snowing like it really means it now...
Thats nice!!!
Took a little while to load...worth it...how gorgeous -- is this your yard??
Patrap, are you lurking? I have a nice story for you...will save for later if no response.
Thats the camera on my pond... its fairly limited as its wireless... max of 5 connections.
Lovely. If you ever come east, and if I ever get any money, please come set me up! Backyard & camera!
Great shot ORCA ( a frozen Koi Pond in the Canadian Tropics) LoL! serious about the video though. Sorry couldn't resist the cheap shot!
80.2deg. F here with 75% Humidity.
Keep up the good work. I always enjoy.
I need 1-2 of those out in my woods to keep up with all the critters that decide to bump around on my deck at 3am...LOL...what range do they have?
Its much nicer when there is no snow and ice.. and the water fall is running... you can watch the Koi.
It runs wireless G, I have two of them.
They are pretty limited in low light conditions... but pretty good bang for you buck at about $100 each..I have two. I also have underwater lights in the ponds so you can see the koi at night
I can watch them from anywhere in the world.
Howdy Auburn;
Check out www.X10.com
Not here...but it is 25F warmer today than it was yesterday at this time...LOL
Its was all filmed between where I am and Alt...so yea ...The movie Norma Ray was filmed here in town
Biscayne aquifer.. one of the worlds most productive
Wow, quite a bit of history in your area. I remember hearing on CNN recently that the character on Norma Ray, just passed away recently. Did you ever get to see any of the filming, would have been interesting.
This was from a post from Bordonaro. My gosh, if I had handed this in to a Writing for Broadcast class, or even to any of my gov't. managers, it would have been covered with red-ink and slashed, and I would be sent to Remedial Writing!
How about: No one can make accurate forecasts more than 3 days out; it is possible they might be able to get it nearly right about a week out.
YIKES THIS -- a model for WHAT NOT TO WRITE, new show after "WHAT NOT TO WEAR":
There is some concern about NCEP model variability from run to run, particularly at extended ranges beyond 7-8 days. The American Meteorological Society Statement adopted on January 14, 2001, titled "Statement on Seasonal to Interannual Climate Prediction" (Bull. Amer. Met. Soc., 82, 701), states, in part, the limit of predictability for day-to-day weather changes for deterministic forecasts is "in the range of 1-2 weeks." NCEP agrees with this statement and notes that for current state-of-the-art models, the limit of "useful skill" is about 7-8 days. Beyond that range, deterministic numerical weather predictions are characterized by little or no skill and suffer from large run to run variability. However, ensemble or probability forecasts may offer improved predictive skill...
WHOOPS! Speaking of bad writing, Bordonaro did NOT write this mess; pls. see his informative post!
Hmmmmm SWMBO said I could buy that system for Christmas... anyone ever try any of their stuff?
I worked for awhile in the Mill where it was filmed...the movie wasn't far from the truth...and Union is still a bad word here...LOL...Opelika is also in the song by Johnny Cash » I've Been Everywhere...it is kind of a cool place...was stuck back in time for years...but that is changing sadly
X10 has good stuff...I had the Home automation system years ago...I believe it was originally sold at Radio Shack
Ok, I will buy it and add it to my system... more weather/Koi cams
Awake, Bordonaro is one of my favorites on here. I did not see the post, but far be it from me to correct anyone's English on the blog. You know me better than that. I may cringe a little from time to time, but I refrain my ever doing that. If he didn't write it, who did? It sounds as if it were a joke. Can you direct me to the post. I need a good laugh!!!!!
Will add to my as-yet-not-started Blog, under section entitled "One Who Dies With the Most Big-Boy-Toys Wins!"
GROTHAR, are YOU trying to IGNORE "MOI?"
(He always does this to me, folks...sometimes in German...which I refuse to learn out of sheer fear!)
49.99 and you get Night Vision...LOL
I get you auburn. Reminds me of another song, "The Times They are A changin'" Same thing happened to my town on Long Island in which I was born. Probably one of the most beautiful towns you have ever seen. Rolling hills, heavy forest, farms, seaports, and the finest beaches one can imagine. Most of the same families for nearly 300 years. Small town. I had been away many years and actually got teary-eyed when I saw the changes. If you know anything about me. I do not get teary-eyed easily. Progress they call it.
Progress sucks sometimes....
Awake, was ist los? Ich habe schon geschrieben die Antwort. Sieh auf! Try refresh and look at my response!!!! It is practically impossible for one to ignore you. LOL
Oh, so there you are, finally, late again. I never wait at the bar more than a half-hour for a date. By then if I'm lucky someone has taken pity and bought me a mercy drink!
As for your post, LOL, pffft, uh huh. And Bordonaro is MY friend...he keeps me company while waiting for YOU. See 1005, btw. And it's in the book under "BAD Writing In Government."
This is picture of our Harbor on Long Island.
well, at least we know where JFV is working!!!!
Yes, that is quite the advantage, esteemed Sir Cheif (sic, LOL)!
My offer still stands: TRADE?? (I figure if I keep nagging, someone will finally cave.)
It has to be atleast cool in Dec
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