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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Humor in Comments
what posts would u like to discredit me on????
What????
ROFL, what did you do to deserve such attention Aus? You have to remember, some of the people posting these remarks have obviously not had their morning coffee yet.. or they would understand how stupid their remarks look.
I agree with you totally
It was a comment made using your name in jest, Aussie. I had to hit "show" a few mins. ago to follow back conversation. Not my idea of a great way to start a new day...but you might want to read back a little.
from Dr. Masters.
I "see" and hear you on that, JF.
Suggest you just enjoy your coffee and have a pleasant drive this moring; otherwise you're going to be VERY late to work!
ROFL.. I wasn't talking about that one :)
It was one previous to it.. I hit the wrong comment to quote... not enough coffee :)
I have read back from when i posted about Mr. Al Gore
The green line is the version we saw above as part of the IPCC report, and the red line is the full series — which goes down rather dramatically, instead of up as the story suggested. If the full Briffa series had been included, the figure would look rather different. The hook upward, the blade of the hockey stick, would have been much less dramatic, the implied global warming much less significant. By truncating the data as they did, the global warming looks much worse.
He put up a link to an article last eve that reported Gore saying billions of peoples water supply would be threatened by AGW.
He made the grevious error of captioning it with: "Al Gore is at it again".
For that he gets abused by Patrap.
Just keeping the record accurate.
Radar
From this RADAR, Tropical Cyclone Laurence has made landfall
Australian Government Bureau of Meteorology
Western Australia
TOP PRIORITY FOR IMMEDIATE BROADCAST
TROPICAL CYCLONE ADVICE NUMBER 35
Issued at 9:00 pm WST on Tuesday, 15 December 2009
BY THE BUREAU OF METEOROLOGY
TROPICAL CYCLONE WARNING CENTRE PERTH
A Cyclone WARNING is current for coastal areas from Kalumburu to Derby,
extending inland to include Drysdale River and Mt Barnett.
A Cyclone WATCH is current for coastal areas from Derby to Beagle Bay.
At 8:00 pm WST Severe Tropical Cyclone Laurence, Category 3 was estimated to be
90 kilometres north northeast of Kuri Bay and
200 kilometres northeast of Cockatoo Island and
moving southwest at 13 kilometres per hour.
Severe Tropical Cyclone Laurence is a small but intense tropical cyclone moving
southwest close to the Kimberley coast. VERY DESTRUCTIVE WINDS with gusts to 220
kilometres per hour are being experienced close to the system centre and are
expected to extend along the coast to Kuri Bay overnight.
GALES with gusts to 100 kilometres per hour should extend further southwest
along the coast, reaching Cockatoo and Koolan Islands later Wednesday morning
and should the centre pass close by VERY DESTRUCTIVE winds are possible during
the middle part of the day. GALES may extend to Derby and Beagle Bay by
Thursday.
HEAVY RAIN is expected to continue over the north Kimberley region, extending
into the western Kimberley overnight. Daily rainfall totals in excess of 100mm
are possible near the coast with totals decreasing further inland.
FESA-State Emergency Service advises of the following community alerts:
RED ALERT: People in or near Kuri Bay need to go to shelter immediately.
YELLOW ALERT: People at or near Mitchell Plateau should be taking action.
BLUE ALERT: People in or near the communities of Koolan Island and Cockatoo
Island
should start taking precautions.
ALL CLEAR: People in Kalumburu are advised that wind danger has passed but you
need to take care to avoid any danger caused by the heavy rain.
Details of Severe Tropical Cyclone Laurence at 8:00 pm WST:
.Centre located near...... 14.8 degrees South 124.9 degrees East
.Location accuracy........ within 30 kilometres
.Recent movement.......... towards the southwest at 13 kilometres per hour
.Wind gusts near centre... 220 kilometres per hour and weakening
.Severity category........ 3
.Central pressure......... 960 hectoPascals
The next advice will be issued by 12:00 am WST Wednesday 16 December
COPENHAGEN – A showdown between the world's two largest polluters loomed over the U.N. climate talks Tuesday as China accused the United States and other rich nations of backsliding on their commitments to fight global warming.
Trying to ease the tension, U.N. Secretary-General Ban Ki-moon said rich and poor countries must "stop pointing fingers" and should increase their pledges to cut greenhouse gas emissions to salvage the faltering talks on a climate pact.
The 27-nation European Union, meanwhile, called on both the U.S. and China to increase their commitments on emissions cuts.
Ban's warning in an interview with The Associated Press came as world leaders started arriving in Copenhagen, kicking the two-week conference into high gear in its quest to deliver a deal to curb emissions of the heat-trapping greenhouse gases that cause global warming.
Key issues remain, however, and the conference so far has been marked by sharp disagreements between China and the United States and deep divisions between rich and poor nations.
China and other developing countries are resisting U.S.-led attempts to make their cuts in emissions growth binding and open to international scrutiny rather than voluntary.
China, the world's largest polluter, is grouped with developing nations at the talks but the U.S. doesn't consider China a nation in need of climate change aid.
In Beijing, China accused developed countries Tuesday of trying to escape their obligations to help poor nations fight climate change.
"We still maintain that developed countries have the obligation to provide financial support," Foreign Ministry spokeswoman Jiang Yu said, adding that was "the key condition for the success of the Copenhagen conference."
President Barack Obama and Chinese Prime Minister Wen Jiabao are among more than 110 world leaders expected in Copenhagen this week.
The U.S. has offered 3-4 percent cut in emissions by 2020 from 1990 levels. China has pledged to cut "carbon intensity" — a measure of carbon dioxide emissions per unit of production — by 40-45 percent by 2020, compared with 2005 levels. But neither offer impressed the EU.
"We expect them both to raise ambition level," said EU environment spokesman Andreas Carlgren. "Otherwise we won't be able to reach the 2 degree target."
Scientists have warned that commitments to cut or slow emissions so far fall short of what is needed to keep global temperature increases below 2 degrees C (3.6 F) above preindustrial levels and head off the worst of global warming.
Ban said he remains cautiously optimistic about a successful outcome at Copenhagen, but warned that negotiators must work out their differences and not leave major problems for world leaders to resolve.
"This is a time where they should exercise the leadership," Ban said. "And this is a time to stop pointing fingers, and this is a time to start looking in the mirror and offering what they can do more, both the developed and the developing countries."
He said all nations "must do more" to keep carbon emissions below dangerous levels and rich countries should step up commitments to provide a steady flow of money for poor countries to combat climate-linked economic disruptions such as rising seas, drought and floods.
Speaking to The AP at a hotel in Copenhagen, Ban said if negotiators cannot resolve those problems before the world leaders arrive "the outcome will be either a weak one, or there will be no agreement."
"This will be a serious mistake on the part of the negotiators and the leaders if they go back empty-handed," he said.
Zimbabwe President Robert Mugabe was among the first heads of state to touch down in the Danish capital, avoiding a travel ban imposed by Western nations because he was attending to a U.N. conference. Mugabe was to address the conference on Wednesday.
"The meeting may be taking place on Danish soil but we're playing by U.N. rules and these rules mean that all the world leaders can meet," Danish Prime Minister Lars Loekke Rasmussen told reporters.
British Prime Minister Gordon Brown was also expected later Tuesday — a day earlier than planned to help push the talks forward.
The U.N. conference's working groups were finishing up two years of work Tuesday and drawing up their final recommendations on such issues as deforestation, technology transfers and the registration of plans by developing countries to control their emissions.
Drafts on those issues showed some narrowing of gaps but left many disputes to be decided by environment ministers, which ultimately may go up to the heads of state.
Conference President Connie Hedegaard said environment ministers already in Copenhagen had worked late into the night Monday to resolve outstanding issues.
"Ministers have to be very clear and focused over the next 48 hours if we are to make it," she said.
Talks hit a snag Monday when developing countries walked away temporarily from the negotiations, fearing industrial countries were backpedaling in their promises to cut greenhouse gases.
The issues concern the details of a final treaty to be negotiated over the next six to 12 months and may not even be included in the political deal reached in Copenhagen.
"The options take us closer to the final agreement, not just the political declaration," said Gustavo Silva-Chavez of the Environmental Defense Fund.
Former U.S. Vice President Al Gore, who was having lunch Tuesday with the U.N. chief, told the conference on Monday that new data suggests a 75 percent chance the entire Arctic polar ice cap may disappear in the summer as soon as five to seven years from now.
Scientists say global warming will create rising sea levels, increasing drought, more extreme weather and the extinction of some species.
linked.. http://news.yahoo.com/s/ap/20091215/ap_on_sc/climate
Thah is correct, and i did say, Al Gore is at it again.
ROFL, you have to give Mr Gore credit, where credit is due. he is a good businessman. He found a niche in the market.. and is exploiting it to the maximum... and making a fortune. That is what good businessmen do.
Opponents: He goes and professes himself a science idiot, giving us all a moment of side-splitting laughter when he utters, with certainty, something dead wrong about planet earth. (I do not mean AGW theory, I mean that which we know and have effectively measured).
Proponents: He goes and professes himself a science genius, giving you all a moment of real exposure of AGW-doom scenarios to millions, with certainty, which most viewers accept as fact.
Outside of that he is a politician and is not a worthy topic of discussion here any more than any other politician.
SO GIVE IT A REST.
Saying "AL Gore is at it again" isn't "slander". It isn't "libel" either.
Yeah, yeah, I'm just chopped liver, lol.
There's not enough coffee in the world, Orca!
You keeping Canada safe from Alaska this morning?
I guess he wasn't earning enough from being an ex V.P, doing conference talks and the like that normal ex V.P's do.
And it diverged significantly from the surface temp record, which they badly wanted to splice on at the end. And that leads to some serious questions about the ability of tree ring studies to accurately represent temperatures of the past.
This is why I, personally, have been denying any claim based on tree ring studies for the last ~4 years. Any scientific conclusion that has tree ring data at the roots of it's logic need to be reworked, IMO.
Oh thanx for posting what the poster said... i have him on ignore
Welcome.
If i had of called Al Gore a name then that could be a problem... but i didn't and never will... i respect his opinion even though his facts are wrong
I am just glad Alaska is taking their weather back.. its been stupid here.... cold and gasp... snow :(
I've found it better if you ignore any stories that have "Gore" and "Global Warming" in them.
BTW, exactly what science background does Gore have?
NONE
Laurence brings rain to Kimberley
The community of Kalumburu, in the far north of the Kimberley, is experiencing heavy rain as a result of Tropical Cyclone Laurence.
The category three system is moving in a south west direction towards the small community, and is recording wind gusts up to 185 kilometres an hour near the coast.
The owner of Kalumburu's general store, Graham Mills, says the gusty winds haven't reached the community, but residents are prepared.
"They're just staying indoors, they've all got their torches and batteries and stocked up on a few tinned foods things, a little bit of tobacco and a couple of decks of cards to entertain themselves," he said.
Tropical Cyclone Laurence is expected to briefly cross the West Australian Coast in the next few hours, as it passes over peninsulas on the Admiralty Gulf.
The Category 3 storm is expected to move fully onshore tomorrow afternoon, and will continue to bring heavy showers and destructive winds to remote northern communities over the next 24 hours.
Laurence is 120 kilometres west of Kalumburu, and is described by the Bureau of Meteorology as a small but intense system.
A yellow alert remains current for Kalumburu and the Mitchell Plateau.
A blue alert is in place for Kuri Bay and Cockatoo Island.
- ABC
River flooding forecast to get into homes tonight, tomorrow, and beyond, in a number of places.
At 20 feet: SECONDARY ROADS IN THE VICINITY OF THE RIVER WILL FLOOD. HOMES CLOSE TO THE RIVER AND PORTIONS OF THE HIDDEN SPRINGS RESORT PARK WILL BE FLOODED. THERE WILL BE WIDESPREAD FLOODING OF PASTURE AND FARM LAND.
At 18 feet: RIVER GARDENS SUBDIVISION WILL BE MODERATELY FLOODED WITH SEVERAL STREETS IMPASSABLE AND A FEW HOMES FLOODED IN THE VICINITY OF GUM BAYOU. A FEW HOMES WILL ALSO BE THREATENED IN MAGNOLIA FOREST. SECONDARY ROADS TO THE RIVER AND THROUGHOUT HONEY ISLAND SWAMP WILL REMAIN INUNDATED.
At 18 feet: EVACUATION OF TRAILERS AT HIDDEN OAKS MUST BE COMPLETED. WATER COVERS THE ENTRANCE TO CAMP GROUNDS. SECONDARY ROADS AND UNIMPROVED ROADS NORTH OF ROBERT WILL FLOOD AS CHAPPEPEELA CREEK BACKS UP. LOW PLACES ON HIGHWAY 22 SOUTH OF ROBERT WILL BE UNDER WATER.
Sand bag locations for St. Tammany: http://www.nola.com/news/index.ssf/2009/12/rains_cause_closures_in_folsom.html
WUmail me if you need some help with that, I would be glad to come sling 'em with ya.
I didn't say anything about the source (irrelevant at this point), I have posted actual peer reviewed stuff that shows the tree ring data to erroneously show a stable historical temperature, and you believed it false simply because I posted.
Which raises one question...why are you talking to me at all if you throw out what I say because I said it? Makes any discussion with you pointless.
Sorry if this offends, but mama taught me to be honest, so I am doing so. Unfortunately, brutal honesty is what comes out in certain circumstances.
I no my gazintas...
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