Arctic sea ice loss tied to unusual jet stream patterns
Earth has seen some highly unusual weather patterns over the past three years, and three new studies published this year point to Arctic sea loss as a potential important driver of some of these strange weather patterns. The record loss of sea ice the Arctic in recent years may be increasing winter cold surges and snowfall in Europe and North America, says a study by a research team led by Georgia Institute of Technology scientists Jiping Liu and Judith Curry. The paper, titled "Impact of declining Arctic sea ice on winter snowfall", was published on Feb. 27, 2012 in the online early edition of the journal Proceedings of the National Academy of Sciences. "Our study demonstrates that the decrease in Arctic sea ice area is linked to changes in the winter Northern Hemisphere atmospheric circulation, said Judith Curry, chair of the School of Earth and Atmospheric Sciences at Georgia Tech, in a press release. "The circulation changes result in more frequent episodes of atmospheric blocking patterns, which lead to increased cold surges and snow over large parts of the northern continents."
Figure 1. Arctic sea ice in September 2007 reached its lowest extent on record, approximately 40% lower than when satellite records began in 1979. Sea ice loss in 2011 was virtually tied with the ice loss in 2007, despite weather conditions that were not as unusual in the Arctic. Image credit: University of Illinois Cryosphere Today.
Figure 2. The extent of Arctic sea ice loss in the summer July - August - September period in 2007 was about 1.4 million square miles (3.6 million square kilometers) greater than in 1980, according to the University of Illinois Cryosphere Today. For comparison, the lost ice coverage (orange colors) was equal to an area about 44% of the size of the contiguous U.S., or 71% of the non-Russian portion of Europe.
Summertime Arctic sea ice loss: 40% since 1980
The Arctic has seen a stunning amount of sea ice loss in recent years, due to melting and unfavorable winds that have pushed large amounts of ice out of the region. Forty percent of the sea ice was missing in September 2007, compared to September of 1980. This is an area equivalent to about 44% of the contiguous U.S., or 71% of the non-Russian portion of Europe. Such a large area of open water is bound to cause significant impacts on weather patterns, due to the huge amount of heat and moisture that escapes from the exposed ocean into the atmosphere over a multi-month period following the summer melt. The Georgia Tech study found that Arctic sea ice loss had caused a 20 - 60% weakening of the west-to-east belt of winds circling the pole in recent years, producing broader meanders in the jet stream that allowed it to get "stuck" in place 20 - 60% more often. When the jet stream gets stuck in place for a long period of time, we say a "blocking pattern" has set up. Since the jet stream marks the boundary between cold, Arctic air to the north, and warmer subtropical air to the south, areas on both sides of the jet are subjected to extended periods of unusually warm or cold weather during a blocking episode. Such a blocking pattern began on January 26, 2012 and lasted until February 11, bringing and exceptionally cold and snowy conditions to much of Europe, which lay on the cold side of an elongated loop of the jet stream that got stuck in place. Conversely, most of North America and northern Siberia saw unusually warm temperatures during this period, since they were on the warm side of the jet stream. Lead author Jiping Liu, a senior research scientist in the School of Earth and Atmospheric Sciences at Georgia Tech, added, "We think the recent snowy winters could be caused by the retreating Arctic ice altering atmospheric circulation patterns by weakening westerly winds, increasing the amplitude of the jet stream and increasing the amount of moisture in the atmosphere. These pattern changes enhance blocking patterns that favor more frequent movement of cold air masses to middle and lower latitudes, leading to increased heavy snowfall in Europe and the Northeast and Midwest regions of the United States." The paper concludes: "if Arctic sea ice continues as anticipated by climate modeling results, we speculate that episodes of the aforementioned circulation change will become more frequent, along with more persistent snowstorms over northern continents during winter."
Figure 3. Waiting for the warm-up after a rare snowfall in Italy during the February, 2012 European cold blast. Image credit: wunderphotographer cathykiro.
Two other studies link Arctic sea ice loss to atmospheric circulation changes
"The question is not whether sea ice loss is affecting the large-scale atmospheric circulation...it's how can it not?" That was the take-home message from Dr. Jennifer Francis of Rutgers University, in her talk "Evidence Linking Arctic Amplification to Extreme Weather in Mid-latitudes, presented at December's American Geophysical Union meeting in San Francisco. Dr. Francis presented new research that has just been published in the journal Geophysical Research Letters, which shows that Arctic sea ice loss may significantly affect the upper-level atmospheric circulation, slowing its winds and increasing its tendency to make contorted high-amplitude loops. High-amplitude loops in the upper level wind pattern (and associated jet stream) increases the probability of persistent weather patterns in the Northern Hemisphere, potentially leading to extreme weather due to longer-duration cold spells, snow events, heat waves, flooding events, and drought conditions. Dr. Francis describes her work in a March 5, 2012 post on the Yale environment360 web site.
"Even if the current weather situation may seem to speak against it, the probability of cold winters with much snow in Central Europe rises when the Arctic is covered by less sea ice in summer." That was the opening sentence of a January 26, 2012 press release by a group of European scientists, led by Ralf Jaiser of the Alfred Wegener Institute in Germany. The words proved prescient, because that day marked the beginning of a brutal two-week cold air outbreak over Central and Eastern Europe that killed 823 people and did over $660 million in damage, according to preliminary estimates by insurance broker Aon Benfield. Dr. Jaiser's team, using modeling studies, showed that Arctic sea ice loss weakens upper-level winds over the Arctic in winter, allowing an increased chance of cold air surges over Europe.
Figure 4. Digging out in Maryland after "Snowmageddon" on February 4, 2010. Image credit: wunderphotographer chills.
Why was the winter of 2011 - 2012 so warm in the U.S.?
The winter of 2011 - 2012 in North America was unusually warm--the fourth warmest on record. The cold air spilling out of the Arctic during the winter was confined to Europe, unlike that previous two winters, which were unusually cold and snowy in the Eastern U.S. Obviously, loss of Arctic sea ice is not having the same impact each winter; such factors as El Niño/La Niña, the phase of the 11-year sunspot cycle, and the amount of snow cover in Siberia also have strong influences on the winter weather pattern that sets up. Cold air is less likely to spill out of the Arctic during a solar maximum, as we are now headed towards, so this factor may tend to reduce the odds of getting big cold blasts in the U.S. during the coming two winters. However, cold air may be more likely to spill out of the Arctic in winter due to the decades-long pattern of warming and cooling of Atlantic Ocean waters known as the Atlantic Multidecadal Oscillation (AMO). A 2012 study by NASA scientists found that the warm phase of the AMO (like we have been in since 1995) causes more instances of atmospheric blocking, where the jet stream gets "stuck" in place, leading to long periods of extreme weather. It will be interesting to see how all these factors play out in the coming years. If these three newly-published studies are correct, the U.S. should see more winters like 2010 - 2011 and 2009 - 2010 in coming decades, as Arctic sea ice continues to melt and affect global atmospheric circulation patterns more strongly.
References
Francis, J.A., and S.J. Vavrus (2012), "Evidence linking Arctic amplification to extreme weather in mid-latitudes," Geophysical Research Letters, 21 February, 2012.
Jaiser, R., K. Dethloff, D. Handorf, A. Rinke, J. Cohen (2012), Impact of sea ice cover changes on the Northern Hemisphere atmospheric winter circulation, Tellus A 2012, 64, 11595, DOI: 10.3402/tellusa.v64i0.11595
Liu et al. (2012), "Impact of declining Arctic sea ice on winter snowfall", Proc. Natl. Academy of Sciences, Published online before print February 27, 2012, doi: 10.1073/pnas.1114910109
Jeff Masters
Reader Comments
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Even that graph doesn't do justice to the situation. Many of those new highs completely smashed the old records by many degrees.
Really? I'm a little more conservative with that. I think the projections in the past estimated around 2050, but recent studies suggest more like the 2030's or something like that because of the feedback loops in ice volume that weren't being taken into account on climate models. I can't personally go any earlier than the recent data. What is it that makes you think it could be earlier?
No, CO2 is not driving the weather patterns. However, it is having a large effect on the climate.
Personally, I think we are far, far closer to having an ice-free summer in the Arctic than 20 years.
Good luck with that!
Magnitude 6.3 - OAXACA, MEXICO
2012 April 02 17:36:43 UTC
This event has been reviewed by a seismologist.
Magnitude 6.3
Date-Time
Monday, April 02, 2012 at 17:36:43 UTC
Monday, April 02, 2012 at 12:36:43 PM at epicenter
Location
16.477°N, 98.287°W
Depth
12.3 km (7.6 miles)
Region
OAXACA, MEXICO
Distances
27 km (17 miles) SSE (148°) from Ometepec, Guerrero, Mexico
33 km (21 miles) WNW (302°) from Pinotepa Nacional, Oaxaca, Mexico
109 km (68 miles) SW (216°) from Tlaxiaco, Oaxaca, Mexico
176 km (109 miles) SE (133°) from Chilpancingo, Guerrero, Mexico
179 km (111 miles) ESE (103°) from Acapulco, Guerrero, Mexico
Location Uncertainty
horizontal +/- 15 km (9.3 miles); depth +/- 7.7 km (4.8 miles)
Parameters
NST=379, Nph=379, Dmin=329.5 km, Rmss=1.01 sec, Gp= 47°,
M-type=regional moment magnitude (Mw), Version=B
Source
Magnitude: USGS NEIC (WDCS-D)
Location: USGS NEIC (WDCS-D)
Event ID
usc0008ui2
So did you write that blog entry?
Somewhat and less so good news: Large structures such as coastal defense systems could be relatively stable, provided they are anchored in the basement at a depth of 60-80feet below the land surface. [NewOrleans levees are anchored ~14feet below the surface, if I remember correctly]
Bad news: Sea level has risen more than 8inches during the past century, 5times higher compared to the pre-industrial millennium.
BAD news: The main concern is the continued acceleration of sea-level rise. [The lower subsidence rate means that] sea-level rise has already been a larger factor in the loss of coastal wetlands than was previously believed.
NEXRAD Radar
Base Reflectivity 0.50° Elevation
Range 124 NMI
MESOSCALE DISCUSSION 0414
NWS STORM PREDICTION CENTER NORMAN OK
1248 PM CDT MON APR 02 2012
AREAS AFFECTED...MUCH OF SC...ERN/NRN GA...ERN TN...WRN NC
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 021748Z - 021915Z
ISOLATED TO SCATTERED THUNDERSTORMS ARE FORECAST TO DEVELOP THIS
AFTERNOON ACROSS MUCH OF SC...ERN/NRN GA...ERN TN AND WRN NC. A FEW
STORMS WILL BE CAPABLE OF PRODUCING LARGE HAIL AND DAMAGING WINDS.
HOWEVER...AN ORGANIZED SVR WEATHER THREAT IS NOT APPARENT
ATTM...WHICH WILL PRECLUDE THE NEED FOR A WW.
SURFACE OBSERVATIONS AT 17Z SHOW A COLD FRONT LOCATED FROM CNTRL KY
SEWD INTO NC...AND SHORT-TERM MODEL GUIDANCE INDICATES IT WILL ENTER
SC BY MID TO LATE AFTERNOON. THE AIRMASS AHEAD OF THE FRONT IS
CHARACTERIZED BY SURFACE TEMPERATURES IN THE UPR 70S TO MID
80S...WITH DEWPOINTS IN THE MID-UPR 50S TO LOW 60S. WITH ADDITIONAL
SURFACE HEATING...MLCAPE VALUES UP TO 1500 J/KG WILL BE POSSIBLE. IN
ADDITION...LOW-LEVEL LAPSE RATES ARE QUICKLY STEEPENING ACROSS THE
REGION...WHICH APPEARS TO BE AIDING IN CAP REMOVAL AND SUBSEQUENT
DEEPENING CUMULUS OVER THE SRN APPALACHIANS. THIS DESTABILIZATION
WILL FAVOR THUNDERSTORM DEVELOPMENT BOTH ALONG AND AHEAD OF THE COLD
FRONT DURING THE NEXT FEW HRS. DESPITE GENERALLY WEAK NWLY
DEEP-LAYER SHEAR...MODERATE INSTABILITY AND A WELL-MIXED BOUNDARY
LAYER WILL FAVOR MULTICELL CLUSTERS POSING SOME THREAT FOR LARGE
HAIL AND DAMAGING WIND GUSTS DURING THE AFTERNOON.
..GARNER.. 04/02/2012
NWS STORM PREDICTION CENTER NORMAN OK
1215 PM CDT MON APR 02 2012
AREAS AFFECTED...ARKLATEX REGION EWD/SEWD INTO THE LOWER MS VALLEY
CONCERNING...SEVERE THUNDERSTORM WATCH 126...
VALID 021715Z - 021845Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 126 CONTINUES.
BOWING MCS CONTINUES MOVING GENERALLY NEWD ACROSS E TX/SWRN LA. AS THE BOW SHIFTS BOTH NEWD AND EWD ACROSS WW 126 WITH TIME...ISSUANCE OF ONE OR MORE ADDITIONAL WATCHES IS EXPECTED.
LATEST RADAR IMAGERY SHOWS THE BOWING MCS EXPANDING AND INTENSIFYING AS IT MOVES ACROSS E TX AND WRN LA...AS DIURNAL HEATING OF THE MOIST
BOUNDARY LAYER IS RESULTING IN ADDITIONAL AIRMASS DESTABILIZATION. WHILE DEEP-LAYER WIND FIELD REMAINS SOMEWHAT MODEST...THE ALREADY WELL-ORGANIZED SYSTEM -- WITH 50 KT REAR INFLOW JET OBSERVED AT 1 KM VIA KLCH /LAKE CHARLES LA/ WSR-88D VWP -- SHOULD REMAIN INTACT THIS AFTERNOON.
GIVEN THIS LEVEL OF ORGANIZATION AND AN INCREASINGLY
UNSTABLE ENVIRONMENT...DEGREE OF WIND/HAIL POTENTIAL WILL LIKELY JUSTIFY ADDITIONAL WW ISSUANCE. AS STORMS ON THE NRN FRINGE OF THE BOW CONTINUE NWD...A WW N OF THE CURRENT WW IS ANTICIPATED...AND SIMILAR NEW WATCH REQUIREMENT IS ENVISIONED INTO MS AS STORMS MOVE ENEWD TOWARD THE MS RIVER VALLEY.
..GOSS.. 04/02/2012
StL in mid 80s already, record for today is 88, likely to be broken.
he gives a 4 for an area, and thats within 50 miles. so within 20 miles, it would be 20% from SPC. and that isnt even close to being issued...his values i find bout useless.
yes, i am the only SPLbeater here lol
I am sorry let me clarify. I realize that "the SPLbeater" is the author of the blog, however are you the author of those words and sentence structure. Did you write that from scratch or did you copy and paste that from somewhere else?
They should really make those things bigger, you know?
The 2007-2008 season would be no different, except that year the final four SEC tournament was interrupted by a weather event in downtown Atlanta that had never happened before in the history of the grand old city.
In case you've forgotten, pay close attention to what you're about to see and hear.
I had posted this on another blog. I believe that it is valid to use here as well:
"Looks like we are going to be skating on a lot of thin ice this summer, boys. That is if the winds and currents don't float it all out first. Then what? ... Water skiing, anyone?"
NATIONAL WEATHER SERVICE STATE COLLEGE PA
134 PM EDT MON APR 2 2012
...WIDESPREAD FROST AND FREEZE EXPECTED TONIGHT...
PAZ017>019-024-025-045-046-049>053-058-030145-
/O.NEW.KCTP.FZ.W.0003.120403T0600Z-120403T1200Z/
CLEARFIELD-NORTHERN CENTRE-SOUTHERN CENTRE-CAMBRIA-BLAIR-
SOUTHERN CLINTON-SOUTHERN LYCOMING-UNION-SNYDER-MONTOUR-
NORTHUMBERLAND-COLUMBIA-SCHUYLKILL-
INCLUDING THE CITIES OF...DUBOIS...CLEARFIELD...PHILIPSBURG...
STATE COLLEGE...JOHNSTOWN...ALTOONA...LOCK HAVEN...WILLIAMSPORT...
LEWISBURG...SELINSGROVE...DANVILLE...SUNBURY...SH AMOKIN...
BLOOMSBURG...BERWICK...POTTSVILLE
134 PM EDT MON APR 2 2012
...FREEZE WARNING IN EFFECT FROM 2 AM TO 8 AM EDT TUESDAY...
THE NATIONAL WEATHER SERVICE IN STATE COLLEGE HAS ISSUED A FREEZE
WARNING...WHICH IS IN EFFECT FROM 2 AM TO 8 AM EDT TUESDAY.
* TEMPERATURES...LOWS AROUND 30.
* TIMING...LATER TONIGHT THROUGH EARLY TUESDAY MORNING.
* IMPACTS...POSSIBLE DAMAGE TO TENDER VEGETATION.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
A FREEZE WARNING IS ISSUED WHEN SUB-FREEZING TEMPERATURES ARE
FORECAST TO THREATEN OUTDOOR PLANTS. THOSE WITH AGRICULTURAL OR
GARDENING INTERESTS IN THE WARNED AREA ARE ADVISED TO HARVEST OR
PROTECT TENDER VEGETATION. POTTED PLANTS NORMALLY LEFT OUTDOORS
SHOULD BE COVERED OR BROUGHT INSIDE.
&&
$$
It will start in a few years... Don't tell Mann. He will try to hide it like he did with Little Ice age and let's not forget about Medieval Warming period...
http://www.sciencedirect.com/science/article/pii/ S1364682612000417
Even I found it to be plagiarized. SPL, there's no way that's your writing. We all know the way you type. Plagiarism is a very, very serious offense and it could result in prison.
I'd bet that they are going to be very conservative with their numbers,
and that the end-of-the-season total will be noticeably higher.
ScienceDaily (Apr. 1, 2012) — A new study contrasting ocean temperature readings of the 1870s with temperatures of the modern seas reveals an upward trend of global ocean warming spanning at least 100 years.
Read more: http://www.sciencedaily.com/releases/2012/04/1204 01135345.htm
Hard to make a clear determination one way or the other based on personal observation; life spans are too short but I can say this: animals that were never seen in central Missouri are showing up in droves. I grew up here and never saw an armadillo until I went to Texas the first time. Now I can pick them up as road kill as far north as Hannibal.
I await your cooling period with much anticipation; I have always enjoyed a cooler climate. Is there some timeframe you're enamored of, or is this a "just around the bend" sort of thing? I certainly understand the uncertainty of all things climatic; I mean the Climate Change adherents have all said that springs will get earlier and earlier, warm climate animals will be seen firther north and weather events more chaotic and harder to predict...oh wait, that has been happening...
To what evidence do you attribute your belief in an impending cooling of the climate?
I made those words from scratch! is there a reason for you suspecting me for copying?
I AM NOT PLAGIARIZING!!!!!!!
Here are the SST anomalies for the past four weeks
What has changed? Pressures over the subtropical Atlantic have gone from above average to below average. In the first half of March, and actually most of winter, we saw above average pressure in these regions. This increased the pressure gradient between the subtropics and the tropics resulting in stronger trade winds. Stronger trade winds means more evaporative cooling, mixing and upwelling. However, over the last couple of weeks, this has changed. Sea level pressure anomalies for the last two weeks are now below average over the subtropical Atlantic.
Should this trend keep up, we would continue to see above normal SSTs into the hurricane season which would obviously promote above average activity. Something to keep an eye on...
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