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
Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 — Blog Index
Use the 30 Minute rule and one can Live to be as old as FLood and I.
Or go Hi-tech and be very cool..!
Check your Wu mail in a minute for my cell number (if you don;t have it already)
O yeah,we gonna have to talk in private.
Speaking of "Theatre of the Absurd," listened in on a 1-hour conference call with HQ (will the pain really stop when I stop banging my head against the wall?)
About this video story, um, is it okay if I chuckle first and feel badly later? The deer should be alright as he will shed his horns sometime this winter!
Link
Good luck NRAamy, I wish you all the best with your treatment.
*is off*
In the US/Canada, remember the old commercials from "Oldsmobile".
"This is not your father's Oldsmobile. This is a new generation of Olds"!
This is not a normal El Nino. The weather pattern is interjecting C PAC moisture into CA, OR, WA and into BC. Unfortunately, this allows bitterly cold, Arctic air to just "dump" out of Central Siberia, AK, then Canada and the CONUS (lower 48 states of the US).
Meanwhile people in Europe are wondering, "Where is winter"? People in parts of Asia are wondering, "Where's the rain/snow"? People in the S Mediterranian are wondering, "Who'll stop the rain"!
At this time of day, the small canines walk me.
Will check back later, sorry I missed some folk.
Amy!! Awake!! Pat!! T-dude!!
(Brad!! Janet!! Dr. Scott!!)
haha great to see you!
Glad to see "your smiling face"! Koala bears eat nuts and berries, sorry!!
I had heard that the Climate talks were suspended, tried to find a recent article, nothing new..
Down there too, at least at Lakefront AP, I see.
Like I told Awake, Christmas has been kicking my behind the last week or so!
If the ECMWF model verifies, ,that willcertainly be the coldest air mass to reach the Gulf Coast and Deep South come next week!
Does that mean we can suspend them here, too? Or does one have to travel to Copenhagen for such indulgence?
LOL yeah, I have been fairly busy studying for finals :P
A BUSY EVENING IN STORE AS A LARGE BAND OF ORGANIZED HEAVY RAINFALL IS APPROACHING ACROSS ACADIANA INTO THE GREATER BATON ROUGE AREA. THIS BAND HAS PRODUCED 2 INCH PER HOUR RATES AND SHOULD MOVE INTO THE BATON ROUGE METRO AREA BY 5 PM...WESTERN PORTIONS OF NEW ORLEANS METRO AREA BY 7 PM. MEANWHILE...LARGE SLUG OF GULF MOISTURE ADVANCING NORTH WITH MORE BANDS OF SHOWERS AND STORMS DEVELOPING DOWNSTREAM OF THE MAIN BAND. NEEDLESS TO SAY...THE FLASH FLOOD WATCH IS WELL WARRANTED AND ONLY CHANGE TO PREVIOUS THINKING IS TO BUMP LOWER END TO 2 TO 3 INCHES WITH LOCALLY 4 TO 6 INCHES. DENSE FOG SEEMS CONFINED TO NEAR WATER AREAS AND WILL MAINTAIN MARINE DENSE FOG ADVISORY OF AREA LAKES AND NEAR SHORE WATERS. OTHERWISE...WILL MENTION FOG IN ZONES BUT FOREGO DENSE FOG ADVISORY FOR LAND AREAS AT THIS TIME AS CONVECTION SHOULD OFFSET DENSE FOG FOR A WHILE.
Harumph. They said "large slug".
The Huffington Post said the African nations who walked out have returned, so the "GW talks" have resumed!!
As percent of normal, well, that is up to 500% of normal.
And as I type, it is raining hard northwest of the Lake...filling out the pinks in the plot above...and will be coming into NOLA metro soon.
I'm well, eyes, thanks...and FrankenFlood is back at work today! He is coming along nicely, I think, and has been in and out of the blog today. Should be back to "regular" status, now.
:)
Save me some effort and post which bays in the Arctic circle are above 20 C? (68 F) Please?
:)
Sandbag locations here: http://www.nola.com/news/index.ssf/2009/12/rains_cause_closures_in_folsom.html
Need a strong-back/weak-mind type person to help sling 'em? WUmail me.
hahahahahahahahahahaha!
;)
Looks like we might be getting 2 to 3 more inches of rain here.....
(Anyone need any mushrooms I have a yard full of them)
Taco :0)
Such indulgence can be enjoyed in both places.
With his impeccable timing, my ride just stopped at my office door and announced that the train is pulling out...so we'll be back later!
(Heading out the door, LMBO @ the shower curtain remark!!!)
Riiiighhttt...
Great!
I still want to know about the 68 F water temps in bays in the Arctic, though...someone needs to move their sensor out of the sewerage lines if it says that in the Arctic circle in December!
Except for N Russia, temps look a bit above normal!!
Not even the buoys off of Nova Scotia are picking up 40 F...much less 68
Quoting the wrong person. atmoaggie was quoting me on a quoted I quoted him, which was quoting someone else. My, I wonder if this is what it is like at Copenhagen.
Widespread ice and snow.
Tropical Cyclone Advice Number 30
TROPICAL CYCLONE LAURENCE, CAT 2 (01U)
8:00 am ACST December 15 2009
==========================================
At 6:30 am CST [5:00 am WST], Tropical Cyclone Laurence, Category 2 (988 hPa) located at 13.4S 126.5E has 10 minute sustained winds of 50 knots with gusts of 70 knots. The cyclone was estimated to be 100 kms north of Kalumburu and 170 kms north northeast of Mitchell Plateau and moving west southwest at 4 knots
Tropical Cyclone Laurence is moving parallel to the Kimberley coast in Western Australia, and is slowly intensifying.
GALES with gusts to 110 kilometres per hour are currently being experienced over the north Kimberley coast between Troughton Island and the mouth of the King George River. These winds are expected to extend further southwest along the coast, reaching as far as Cockatoo Island on Wednesday morning. GALES may extend further southwest as far as Beagle Bay by Thursday. If the cyclone takes a more southerly track, GALES may extend further inland during today.
DESTRUCTIVE WINDS with gusts to 130 kilometres per hour are expected to develop near Troughton Island later today, and may extend southwest along the coast as far as Kuri Bay by Wednesday morning.
HEAVY RAIN is expected to continue over the north Kimberley region today, extending into the western Kimberley during today and Wednesday.
FESA-State Emergency Service advises of the following community alerts:
YELLOW ALERT: People in or near the communities of Kalumburu, Mitchell Plateau and Faraway Bay should be taking action in preparation for the cyclone's arrival.
BLUE ALERT: People in or near the communities of Kuri Bay and Cockatoo Island should start taking precautions
Australian Government Bureau of Meteorology
Northern Territory
Darwin Regional Forecasting Centre
TOP PRIORITY FOR IMMEDIATE BROADCAST
Media: The Standard Emergency Warning Signal should NOT be used with this
warning.
TROPICAL CYCLONE WARNING
TROPICAL CYCLONE ADVICE NUMBER 30
Issued by the BUREAU OF METEOROLOGY, DARWIN
at 8:00 am CST [6:30 am WST] Tuesday 15 December 2009
A Cyclone WARNING continues for coastal areas from Cockatoo Island to Wyndham.
A Cyclone WATCH continues for coastal areas from Beagle Bay to Cockatoo Island.
At 6:30 am CST [5:00 am WST] Tropical Cyclone Laurence, Category 2 was estimated
to be 100 kilometres north of Kalumburu and 170 kilometres north northeast of
Mitchell Plateau and moving west southwest at 8 kilometres per hour.
Tropical Cyclone Laurence is moving parallel to the Kimberley coast in Western
Australia, and is slowly intensifying.
GALES with gusts to 110 kilometres per hour are currently being experienced over
the north Kimberley coast between Troughton Island and the mouth of the King
George River. These winds are expected to extend further southwest along the
coast, reaching as far as Cockatoo Island on Wednesday morning. GALES may extend
further southwest as far as Beagle Bay by Thursday. If the cyclone takes a more
southerly track, GALES may extend further inland during today. DESTRUCTIVE WINDS
with gusts to 130 kilometres per hour are expected to develop near Troughton
Island later today, and may extend southwest along the coast as far as Kuri Bay
by Wednesday morning.
HEAVY RAIN is expected to continue over the north Kimberley region today,
extending into the western Kimberley during today and Wednesday.
FESA-State Emergency Service advises of the following community alerts:
YELLOW ALERT: People in or near the communities of Kalumburu, Mitchell Plateau
and Faraway Bay should be taking action in preparation for the cyclone's
arrival.
BLUE ALERT: People in or near the communities of Kuri Bay and Cockatoo Island
should start taking precautions.
Details of Tropical Cyclone Laurence at 6:30 am CST [5:00 am WST]:
.Centre located near...... 13.4 degrees South 126.5 degrees East
.Location accuracy........ within 35 kilometres
.Recent movement.......... towards the west southwest at 8 kilometres per hour
.Wind gusts near centre... 130 kilometres per hour, and slowly intensifying
.Severity category........ 2
.Central pressure......... 988 hectoPascals
The next advice will be issued by 11:00 am CST Tuesday 15 December[9:30 am WST
Tuesday 15 December].
This advice is available on telephone NT-1300 659 211 and WA-1300 659 210
DARWIN Tropical Cyclone Warning Centre
Conditions at 44258 as of
(6:00 pm AST)
2200 GMT on 12/14/2009: Unit of Measure: English Metric Time Zone: Station Local Time Greenwich Mean Time [GMT] British Summer Time [GMT+1] Eastern Greenland [GMT-1] Azores [GMT-2] Western Greenland [GMT-3] Atlantic Standard [GMT-4] US/Eastern Standard US/Central Standard US/Mountain Standard US/Pacific Standard Alaska Standard [GMT-9] Hawaii-Aleutian Standard [GMT-10] Samoa Standard [GMT-11] International Date Line West [GMT-12] Western European [GMT+0] Central European [GMT+1] Eastern European [GMT+2] Moscow [GMT+3] USSR Zone 3 [GMT+4] USSR Zone 4 [GMT+5] USSR Zone 5 [GMT+6] USSR Zone 6 [GMT+7] China Coast [GMT+8] Japan Standard [GMT+9] Guam Standard [GMT+10] GMT+11 International Date Line East [GMT+12]
Click on the graph icon in the table below to see a time series plot of the last 24 hours of that observation.
Wind Direction (WDIR): N ( 360 deg true )
Wind Speed (WSPD): 13.6 kts
Wind Gust (GST): 15.5 kts
Wave Height (WVHT): 4.6 ft
Dominant Wave Period (DPD): 7 sec
Atmospheric Pressure (PRES): 30.05 in
Pressure Tendency (PTDY): +0.07 in ( Rising )
Air Temperature (ATMP): 39.6 °F
Water Temperature (WTMP): 43.5 °F
Wind Chill (CHILL): 31.1 °F
Combined plot of Wind Speed, Gust, and Air Pressure
Local Text Forecast for
Lake Worth, FL (33461)
Dec 14 Tonight
Mainly clear. Low 71F. Winds E at 5 to 10 mph.
Dec 15 Tomorrow
Sunshine along with some cloudy intervals. Warm. High 83F. Winds ESE at 5 to 10 mph.
Dec 15 Tomorrow night
Generally fair. Low around 70F. Winds light and variable.
Dec 16 Wednesday
Chance of showers. Highs in the low 80s and lows in the upper 60s.
Dec 17 Thursday
Chance of showers. Highs in the mid 70s and lows in the mid 60s.
Dec 18 Friday
Showers possible. Highs in the upper 70s and lows in the mid 60s.
Dec 19 Saturday
Showers. Highs in the upper 70s and lows in the low 60s.
Dec 20 Sunday
More clouds than sun. Highs in the low 70s and lows in the mid 50s.
Dec 21 Monday
Cloudy. Highs in the low 70s and lows in the mid 50s.
Dec 22 Tuesday
Clouds giving way to sun. Highs in the low 70s and lows in the mid 50s.
Dec 23 Wednesday
Sunny. Highs in the low 70s and lows in the upper 50s.
Anybody who would take that one reading and use it to debunk AGW is a moron. It should however, underscore the point that AGW is not the slam-dunk so many make it out to be.
Ok! I was wrong! I thought the European area was experiencing slightly above normal temps/below normal precip.
1497: Yep, been looking at those. The ones out towards the Gulf Stream show 40s...
Viewing: 1451 - 1501
Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 — Blog Index