Florida shivers; Hot Arctic-Cold Continents pattern is back

By: Dr. Jeff Masters , 14. joulukuuta 2010 klo 17:36 (GMT)

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Cold air sweeping southwards behind the fierce snowstorm that roared through the Upper Midwest over the weekend is bringing record low temperatures over much of the Southeast this morning. However, preliminary indications are that Central Florida's orange groves fared better than expected, and there were no reports of widespread damage to the orange crop. Record lows this morning included 32°F at West Palm Beach, 50°F in Key West, and 20°F in Jacksonville. Cold air flowing over the relatively warm waters of Lake Erie and Lake Ontario are creating heavy lake-effect snows, with 5 – 9 inches of new snow expected near Cleveland, OH today, and 2 – 5 inches near Syracuse, NY.

Hot Arctic-Cold Continents
I'm in San Francisco this week for the world's largest gathering of Earth scientists, the annual American Geophysical Union (AGU) conference. Over 15,000 scientists have descended upon the city, and there are a ridiculous number of fascinating talks on every conceivable aspect of Earth science, including, of course, climate change. One talk I attended yesterday was called, "Hot Arctic-Cold Continents: Hemispheric Impacts of Arctic Change.” The talk was given by Dr. Jim Overland of NOAA's Pacific Marine Environmental Laboratory, one of the world's experts on Arctic weather and climate (I spent many long months flying in the Arctic with him during the three Arctic field programs I participated in during the late 1980s.) Dr. Overland discussed the remarkable winter of 2009 – 2010, which brought record snowstorms to Europe and the U.S. East Coast, along with the coldest temperatures in 25 years, but also brought the warmest winter on record to Canada and much of the Arctic. He demonstrated that the Arctic is normally dominated by low pressure in winter, and a “Polar Vortex” of counter-clockwise circulating winds develops surrounding the North Pole. However, during the winter of 2009-2010, high pressure replaced low pressure over the Arctic, and the Polar Vortex weakened and even reversed at times, with a clockwise flow of air replacing the usual counter-clockwise flow of air around the pole. This unusual flow pattern allowed cold air to spill southwards and be replaced by warm air moving poleward. This pattern is kind of like leaving the refrigerator door ajar--the refrigerator warms up, but all of the cold air spills out into the house.


Figure 1. Conceptual diagram of how Arctic sea ice loss affects winter weather, from NOAA's Future of Arctic Sea Ice and Global Impacts web page.

The North Atlantic Oscillation (NAO)
This is all part of a natural climate pattern known as the North Atlantic Oscillation (NAO), which took on its most extreme configuration in 145 years of record keeping during the winter of 2009 – 2010. The NAO is a climate pattern in the North Atlantic Ocean of fluctuations in the difference of sea-level pressure between the Icelandic Low and the Azores High. It is one of oldest known climate oscillations--seafaring Scandinavians described the pattern several centuries ago. Through east-west oscillation motions of the Icelandic Low and the Azores High, the NAO controls the strength and direction of westerly winds and storm tracks across the North Atlantic. A large difference in the pressure between Iceland and the Azores (positive NAO) leads to increased westerly winds and mild and wet winters in Europe. Positive NAO conditions also cause the Icelandic Low to draw a stronger south-westerly flow of air over eastern North America, preventing Arctic air from plunging southward. In contrast, if the difference in sea-level pressure between Iceland and the Azores is small (negative NAO), westerly winds are suppressed, allowing Arctic air to spill southwards into eastern North America more readily. Negative NAO winters tend to bring cold winters to Europe and the U.S. East Coast, but leads to very warm conditions in the Arctic, since all the cold air spilling out of the Arctic gets replaced by warm air flowing poleward.

The winter of 2009 - 2010 had the most extreme negative NAO since record keeping began in 1865. This "Hot Arctic-Cold Continents pattern", resulting in a reversal of Polar Vortex and high pressure replacing low pressure over the Arctic, had occurred previously in only four winters during the past 160 years—1969, 1963, 1936, and 1881. Dr. Overland called the winter of 2009 – 2010 at least as surprising at the record 2007 loss of Arctic sea ice. He suspected that Arctic sea ice loss was a likely culprit for the event, since Francis et al. (2009) found that during 1979 - 2006, years that had unusually low summertime Arctic sea ice 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, allowing cold air to spill out of the Arctic and into Europe and the Eastern U.S. Dr. Overland also stressed that natural chaos in the weather/climate system also played a role, as well as the El Niño/La Niña cycle and natural oscillations in stratospheric winds. Not every year that we see extremely high levels of Arctic sea ice loss will have a strongly negative NAO winter. For example, the record Arctic sea ice loss year of 2007 saw only a modest perturbation to the Arctic Vortex and the NAO during the winter of 2007 – 2008.

However, the strongly negative NAO is back again this winter. High pressure has replaced low pressure over the North Pole, and according to NOAA, the NAO index during November 2010 was the second lowest since 1950. This strongly negative NAO has continued into December, and we are on course to have a top-five most extreme December NAO. Cold air is once again spilling southwards into the Eastern U.S. And Europe, bringing record cold and fierce snowstorms. At the same time, warm air is flowing into the Arctic to replace the cold air spilling south--temperatures averaged more than 10°C (18°F) above average over much of Greenland so far this month. The latest 2-week forecast from the GFS model predicts that the Hot Arctic-Cold Continents pattern will continue for the next two weeks. However, the coldest air has sloshed over into Europe and Asia, and North America will see relatively seasonable temperatures the next two weeks.

For more information
The NOAA web page, Future of Arctic Sea Ice and Global Impacts has a nice summary of the “Hot Arctic-Cold Continents” winter pattern.

NOAA's Arctic Report Card is also a good source of information.

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. Geophys. Res. Lett., 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., and M. Wang, 2010: Large-scale atmospheric circulation changes associated with the recent loss of Arctic sea ice. Tellus, 62A, 1.9.

Petoukhov, V., and V. Semenov, 2010: A link between reduced Barents-Kara sea ice and cold winter extremes over northern continents. J. Geophys. Res.-Atmos., ISSN 0148-0227.

Seager, R., Y. Kushnir, J. Nakamura, M. Ting, and N. Naik (2010), Northern Hemisphere winter snow anomalies: ENSO, NAO and the winter of 2009/10, Geophys. Res. Lett., 37, L14703, doi:10.1029/2010GL043830.

Jeff Masters

Peeking Christmas Lights in Snowy Shrub (UnobtrusiveTroll10)
At my house. Their little heat has created a tiny viewing hole.
Peeking Christmas Lights in Snowy Shrub
Berry Cold Strawberries (lshunter)
Astin Farms in Plant City, FL waters their strawberry crop to prevent damage from frost as temperatures drop into the 20s overnight on December 14, 2010. More cold temperatures expected tonight.
Berry Cold Strawberries

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745. hurricanelonny
17. joulukuuta 2010 klo 20:09 (GMT)
Yep. Models backed off. No Artic blast next week.
Nope. Models back on. On or right after XMAS.

This system and its
associated cold front will transport another shot of modified Arctic
air into S fla with both the GFS and European model (ecmwf) timing the frontal
passage right around or just after sunset on Christmas day with
the cold air filtering in behind the front. Both models also show
the coldest air arriving beyond this forecast package but have had
consistency in their past few runs so all those interested should
keep informed with updated forecasts through the week.

Member Since: 12.08.2010 Posts: 0 Comments: 6
744. hurricanelonny
17. joulukuuta 2010 klo 20:06 (GMT)
Quoting Jeff9641:


EURO doesn't show any cold blast next week. GFS does but not the EURO and I'm willing to bet the Euro will be right again look below and you will see that the MIAMI office has no clue what's going on as the EURO shows no such ARCTIC BLAST.

http://www.coaps.fsu.edu/~maue/tropical/plots/ec850_19.png
Member Since: 12.08.2010 Posts: 0 Comments: 6
743. hydrus
16. joulukuuta 2010 klo 19:14 (GMT)
Quoting Minnemike:
freshly brewed!
Did you see the backward low that traverses the the whole of Southern Canada? (I hope this works)....Link
Member Since: 27.09.2007 Posts: 1 Comments: 19607
742. seflagamma
16. joulukuuta 2010 klo 16:03 (GMT)
Quoting GeoffreyWPB:
Medical: Chill out - cold sensitivity is an individual thing


Nice article and so very true.

I've been very cold sensitive all my life, even when I lived in Mid-South area for 25 years.
That is why I always wanted to go where it is always warm...

but regardless of personally being cold sensitive or not,
when South Florida gets freezes and frosts,
Everyone suffers, in fresh food availability and prices
and the natural tropical wild life..on land or in the sea and fresh waters.


I enjoyed reading the article, thanks!

Member Since: 29.08.2005 Posts: 294 Comments: 40840
741. Minnemike
16. joulukuuta 2010 klo 16:01 (GMT)
Quoting RipplinH2O:
Howdy all...coffee?
freshly brewed!
Member Since: 31.07.2008 Posts: 0 Comments: 1320
740. RipplinH2O
16. joulukuuta 2010 klo 15:53 (GMT)
Howdy all...coffee?
Member Since: 30.07.2010 Posts: 0 Comments: 491
739. Minnemike
16. joulukuuta 2010 klo 15:46 (GMT)
science with absolutism: a few words on this from a philosophical perspective.

our understanding of all things is as fluid as the knowledge we purport to know. there is much to be gained on the order of intellectual wisdom by means of the Socratic paradox, "i know that i know nothing".

the things we think we know now are based on the mistakes of our past. this stands to reason that the things we will know in the future derive from the mistakes we make now, either by thought or by action. i agree with Misanthrope that there is no absolutism in science. the whole art is a best fit practice. that is where he is coming from by some of his more irritable statements about blindness and cowardice. that is also why i cite responsible action based on imagination.
Member Since: 31.07.2008 Posts: 0 Comments: 1320
738. Neapolitan
16. joulukuuta 2010 klo 15:44 (GMT)
Quoting Patrap (#718):
Unstable Antarctica: What's Driving Ice Loss?
12.15.10


That's astounding and depressing at the same time, and further evidence of just how quickly things are heating up. It also correlates nicely with the excellent article to which I linked a few days ago which stated the following: "New analyses of the heat content of the waters off Western Antarctic Peninsula are now showing a clear and exponential increase in warming waters undermining the sea ice, raising air temperatures, melting glaciers and wiping out entire penguin colonies."

You mentioned 19 cubic miles of melt from just one area. I did some calculating, and that's just under 21 trillion gallons of water (20,921,225,799,689.99424, to be precise), or nearly enough to fill nearly 35 million standard Olympic-sized swimming pools. Incredible...

Excellent comment; thanks for posting.
Member Since: 8.11.2009 Posts: 4 Comments: 13306
737. GeoffreyWPB
16. joulukuuta 2010 klo 15:22 (GMT)
Medical: Chill out - cold sensitivity is an individual thing
Member Since: 10.09.2007 Posts: 0 Comments: 10589
736. atmoaggie
16. joulukuuta 2010 klo 15:21 (GMT)
Quoting Minnemike:
i imposed my own ban on myself from discussing the topic further for the benefit of the blog, due to unnecessary and lengthy tit for tat's with Ripplin. i mention an Admin ban based on off topic discussion, if they bother to, but half of us would be hit by that if so... (the Doc never mentions AGW in post, just the NAO and impacts)

and i'm glad to see your reply too Atmo, my memory does serve me correctly. that was what i thought, and i had no recollection of you standing firmly on either platform. i still think your modus operandi limits scope by strict adherence to data, but i also know you are an advocate for far better data. i do believe however, there is a time where responsible action requires imagination. there's a point in which the data need be figured out. otherwise you are no different than the output on a computer screen, relying entirely on the integrity of the input.

we do have eyes and computers in our heads too.
Oh, I see. Fair enough.

Your comment about imagination speaks well to a comment I made last night about everyone's different amount of allowable uncertainty, unknowns, assumptions, etc. which you've wrapped up nicely in one word.

Obviously, we know where many of us fit into that...

Cheers!
Member Since: 16.08.2007 Posts: 6 Comments: 12461
735. Minnemike
16. joulukuuta 2010 klo 14:58 (GMT)
Quoting atmoaggie:
No, I don't think that there is any certainty that the platform is wholly incorrect, either. Nor do I think I've ever typed those words.

Personal ban? WTH? And Admin? For what? I think you need to read further back, too.
i imposed my own ban on myself from discussing the topic further for the benefit of the blog, due to unnecessary and lengthy tit for tat's with Ripplin. i mention an Admin ban based on off topic discussion, if they bother to, but half of us would be hit by that if so... (the Doc never mentions AGW in post, just the NAO and impacts)

and i'm glad to see your reply too Atmo, my memory does serve me correctly. that was what i thought, and i had no recollection of you standing firmly on either platform. i still think your modus operandi limits scope by strict adherence to data, but i also know you are an advocate for far better data. i do believe however, there is a time where responsible action requires imagination. there's a point in which the data need be figured out. otherwise you are no different than the output on a computer screen, relying entirely on the integrity of the input.

we do have eyes and computers in our heads too.
Member Since: 31.07.2008 Posts: 0 Comments: 1320
734. Neapolitan
16. joulukuuta 2010 klo 14:57 (GMT)
Hey, actual tropical weather news: after a three week break, the NHC released their TCR for Hurricane Julia a bit ago. Among the highlights:

--Julia was a bit stronger than thought; the previous top speed was estimated to have been 115 knots, but that has been bumped up to 120 knots;

--Julia was a hurricane for six hours less than previously thought, staying at that status for 84 hours;

--Julia was a major hurricane for six hours longer than previously thought, staying at Cat 3 or better for 30 hours;

--Julia was at tropical storm force or better for 12 hours longer than previously estimated, lasting 192 hours at that status;

--Julia's ACE was raised to 15.5125 (from 14.1825), and the storm's HDP rose from 11.345 to 11.5025;

--Seasonal ACE is now calculated to be 161.15.

The reports states the following: "Julia is the strongest hurricane in the Atlantic hurricane database (HURDAT) to be recorded east of 40 W. However, it is highly unlikely that either this peak intensity as a Category 4 hurricane or its 1.25 day duration as a major hurricane would have been observed for a hurricane in this location before the advent of regular satellite imagery and the Dvorak intensity analysis system in the 1970s. There were no reliable ship or coastal reports of tropical-storm-force or greater winds received in association with Julia. However, it is possible that that some tropical-storm-force winds did affect the southern Cape Verde islands."
Member Since: 8.11.2009 Posts: 4 Comments: 13306
733. Skyepony (Mod)
16. joulukuuta 2010 klo 14:49 (GMT)
Quoting Ameister12:
Why isn't the ABOM designating this?


It's 91S the TCFA was cancelled as it made landfall.
Member Since: 10.08.2005 Posts: 156 Comments: 36173
732. bluheelrtx
16. joulukuuta 2010 klo 14:49 (GMT)
Quoting hurristat:


I say album...

and I'm 17. :P


An music album is a collection of songs. The media format is irrelevant.
Member Since: 8.11.2006 Posts: 5 Comments: 222
731. atmoaggie
16. joulukuuta 2010 klo 14:43 (GMT)
Quoting Minnemike:
in hopes my memory serves me well, is it true then you have also not yet stated with unequivocal certainty that the AGW platform is wholly incorrect? (i.e. a certainty that current warming is a natural cycle not impacted by human activities)

in the case i am remembering falsely, please confirm Mr. Data.
No, I don't think that there is any certainty that the platform is wholly incorrect, either. Nor do I think I've ever typed those words.

Personal ban? WTH? And Admin? For what? I think you need to read further back, too.
Member Since: 16.08.2007 Posts: 6 Comments: 12461
730. aimetti
16. joulukuuta 2010 klo 14:37 (GMT)
good god ,
i havent been on here in a month and you all are still arguing over global warming.

Horrid.
Member Since: 20.08.2009 Posts: 0 Comments: 96
729. Ameister12
16. joulukuuta 2010 klo 14:37 (GMT)
Why isn't the ABOM designating this?
Member Since: 9.08.2009 Posts: 10 Comments: 4504
728. wunderkidcayman
16. joulukuuta 2010 klo 14:37 (GMT)
Hey guys whats going on its been really cool down here in the past couple of days
Member Since: 13.06.2009 Posts: 2 Comments: 9598
727. seflagamma
16. joulukuuta 2010 klo 14:33 (GMT)
Quoting surfmom:
NOT

I'm still totally incredulous you would prefer southern girls frigid and chattering, then hot, sweaty and TAN

be careful Whaleboy -LOL- methinks you're looking for StinkEye *big smile*


I also agree with Surf and Skye, we like to be hot, sweaty and tan!
Member Since: 29.08.2005 Posts: 294 Comments: 40840
726. Skyepony (Mod)
16. joulukuuta 2010 klo 14:30 (GMT)
Totally agree with surfmom. Much better to have us southern girls tan & sweaty than frozen & angry.

Chistmas lights & sheets did well on the tomatoes & cucumbers. Had near a 10 hr freeze night before last with 25.1F as the low. They lived. All the winter veggies~things like brocolli, cabbage, collards, onions, garlic, snow peas look good. Chili pepper died, along with all the last of the summer stuff~ limas, sweet taters, okra.. So far so good with the citrus.

Surf~ Your garlic died back too?
Member Since: 10.08.2005 Posts: 156 Comments: 36173
723. seflagamma
16. joulukuuta 2010 klo 14:22 (GMT)
Quoting surfmom:
coming out of hibernation to post -- We are WARMING
SWFL - SRQ
I am convinced
HELL is a frozen place
my veggie garden is Kaput
transformed from a Sahara Oasis
to some frozen tundra
...there are No birds singing - even my Hens are
on mute.
Checking the garden 6:30AM, Kinda looks like a windswept Chernobyl

Yesterday I had a FIRST TIME experience...had to break ICE in the water troughs -- couldn't believe it!

But thankfully we warm today - at least for a little while


{{Surf}}}

I hear you, I am not going to fight another cold winter here in SE Fla.. if it cannot live in our new "colder climate" then I have to stop planting winter gardens...
and the tropical critters need to travel further south...
the the critters that live in tropical waters, need to go further south into the warmer Caribbean Sea..

I just do not have it in me to keep trying to save my winter garden and my topical plants if this is going to continue for 3 months this winter....

I think I need to move even further South.

Pottery??? you out there??? you have room for another Family on your island???
Member Since: 29.08.2005 Posts: 294 Comments: 40840
722. surfmom
16. joulukuuta 2010 klo 14:16 (GMT)
Quoting Orcasystems:
ROFLMAO... I just looked... exact same temp right now here...as it is in Tampa... now thats funny
NOT

I'm still totally incredulous you would prefer southern girls frigid and chattering, then hot, sweaty and TAN

be careful Whaleboy -LOL- methinks you're looking for StinkEye *big smile*
Member Since: 18.07.2007 Posts: 30 Comments: 26536
721. JRRP
16. joulukuuta 2010 klo 14:16 (GMT)
Member Since: 16.08.2007 Posts: 0 Comments: 5085
720. seflagamma
16. joulukuuta 2010 klo 14:16 (GMT)
Quoting IKE:
My 35,000th post on WU without one timeout. No wall of denial from me....



LOL I am almost there, at 34,863 and never been banned from Dr Master's blog yet, but have from a few personal blogs! LOL

congrats IKE!
Member Since: 29.08.2005 Posts: 294 Comments: 40840
719. surfmom
16. joulukuuta 2010 klo 14:12 (GMT)
coming out of hibernation to post -- We are WARMING
SWFL - SRQ
I am convinced
HELL is a frozen place
my veggie garden is Kaput
transformed from a Sahara Oasis
to some frozen tundra
...there are No birds singing - even my Hens are
on mute.
Checking the garden 6:30AM, Kinda looks like a windswept Chernobyl

Yesterday I had a FIRST TIME experience...had to break ICE in the water troughs -- couldn't believe it!

But thankfully we warm today - at least for a little while
Member Since: 18.07.2007 Posts: 30 Comments: 26536
718. Patrap
16. joulukuuta 2010 klo 14:10 (GMT)
Unstable Antarctica: What's Driving Ice Loss?
12.15.10


When surface winds are strong, they stir the Southern Ocean and lift the warm water (red) onto the continental shelf where the additional heat contributes to melt of the ice shelf.

When surface winds are strong, they stir the Southern Ocean and lift the warm water (red) onto the continental shelf where the additional heat contributes to melt of the ice shelf. Credit: Frank Ippolito Scientists have previously shown that West Antarctica is losing ice, but how that ice is lost remained unclear. Now, using data from Earth observing satellites and airborne science missions, scientists are closing in on ice loss culprits above and below the ice.

The findings, presented Dec. 15 at the fall meeting of the American Geophysical Union (AGU) in San Francisco, Calif., are expected to improve predictions of sea level rise.

Time Not Healing Glacial Wounds

A new analysis by Ted Scambos, a glaciologist at the National Snow and Ice Data Center in Boulder Colo., and colleagues found that more than a decade after two major Antarctic ice shelves collapsed, glaciers once buttressed by the shelves continue to lose ice.

Changes are most evident in the West Antarctic Ice Sheet and along the Antarctic Peninsula. A spine of mountains forces passing winds to give up their moisture as snow, feeding glaciers that in turn feed the ice shelves that jut out into the Southern Ocean. More than a decade ago, dramatic changes started affecting a series of ice shelves, collectively called Larsen, along the Peninsula's northeast coast. In 1995, Larsen A was the first to collapse followed by a larger loss of Larsen B in 2002. Today, a small piece of the Larsen B and the entirety of the vast Larsen C hang on.

Investigating how the glaciers have responded to the loss of these ice shelf "dams," Scambos and colleagues tracked elevation information using data from satellites such as NASA's Ice, Cloud and land Elevation Satellite (ICESat) and previous airborne missions. They show that between 2001 and 2006, glaciers feeding Larsen A and Larsen B lost 12 gigatons of ice loss per year, or 30 percent of all ice lost throughout the Peninsula.

Moreover, the continued draw down of glaciers, such as Drygalski Glacier, fifteen years after the loss of Larsen A, have set precedent for what to expect elsewhere. Losses by glaciers that fed the Larsen B, such as Crane Glacier, are likely to continue.

Scambos and a team of colleagues have now placed instruments on glaciers just south of the area where the shelves disintegrated, anticipating that further warming will lead to further glacier speed-ups. The instruments and new aircraft overflights will provide further insight into shelf break-up and the onset of ice acceleration.


When surface winds are strong, they stir the Southern Ocean and lift the warm water (red) onto the continental shelf where the additional heat contributes to melt of the ice shelf. Credit: Frank Ippolito

Wind Matters

Further south is West Antarctica's Pine Island Glacier, another site of major ice loss presently draining more than 19 cubic miles of ice per year from the West Antarctic Ice Sheet. It continues to deteriorate rapidly and scientists want to know why.

By combining satellite and airborne data, Bob Bindschadler, a glaciologist with the Goddard Earth Sciences and Technology Center at NASA's Goddard Space Flight Center in Greenbelt, Md., has successfully gained more insight into interactions between the atmosphere, ocean and ice even though the data cant reveal these connections directly.

Bindschadler and colleagues looked at images from the Landsat satellite and spotted a series of large surface undulations on the ice shelf. Next they matched the undulations with the timing of warm water pulses in the waters adjacent to the ice shelf. When surface winds are strong, they stir the Southern Ocean and lift the warm water onto the continental shelf where the additional heat contributes to melt.

Airborne data showed the ice shelf was up to 150 meters (492 feet) thinner when the warmer water was present, allowing Bindschadler's team to establish a direct link between the rate of ice shelf melting and atmospheric wind speed. When the team accounted for the heat coming in and the ice lost, they concluded that only 22 percent of the heat is used in melting. Whether the remaining heat might melt additional ice is unknown, but it is clear that the atmospheric circulation has a strong role on the future of the ice shelf and the fate of the ice sheet inland. Stronger winds would lead to an acceleration of ice loss; weaker winds would have a stabilizing effect.

"In short, ice shelves are affected by what winds are doing," Bindschadler said. "As Antarctic Circumpolar winds continue to increase, ice shelves are at increasing risk."


West Antarctica is seeing dramatic ice loss particularly the Antarctic Peninsula and Pine Island regions. Ice loss culprits include the loss off buttressing ice shelves, wind, and a sub-shelf channel that allows warm water to intrude below the ice. Credit: NASA/NSIDC


Underwater Channel Promoting Melt?


A gravity instrument, flown during NASA's Operation IceBridge campaign in 2009, revealed the presence of a sinuous channel (blue) below West Antarctica's Pine Island ice shelf. The channel allows warm ocean water to reach the grounding line, leading to melting of the ice shelf from below. Credit NASA

Taking a closer look at Antarctica's Pine Island Glacier is Michael Studinger, a glaciologist with the Goddard Earth Sciences and Technology Center at NASA Goddard.

Studinger is project scientist for NASA's Operation IceBridge mission -- an airborne science campaign that makes annual surveys of polar snow and ice -- that is helping researchers understand changes to Pine Island and other critical regions along West Antarctica and the Peninsula.

After analyzing data from the mission's first Antarctic deployment in 2009, the team revealed for the first time a curious feature below the Pine Island shelf: a sinuous channel that allows warm ocean water to reach the grounding line, leading to melting of the ice shelf from below.

More information will become available throughout Operation IceBridge, which sustains watch over Earth's poles until the launch of ICESat-2, scheduled for January 2016. In November 2010, teams concluded the second Antarctic campaign during which they flew over sea ice and key glaciers including a return mission over Pine Island Glacier. These data will be incorporated into the tools scientists use to refine estimates of future sea level rise.
Member Since: 3.07.2005 Posts: 415 Comments: 125717
717. Orcasystems
16. joulukuuta 2010 klo 14:09 (GMT)
Complete Update





Member Since: 1.10.2007 Posts: 81 Comments: 26493
716. seflagamma
16. joulukuuta 2010 klo 14:07 (GMT)
Quoting GeoffreyWPB:
BOTH THE GFS AND ECMWF CONTINUE TO INDICATE THAT A MORE
AMPLIFIED PATTERN WILL DEVELOP ACROSS MUCH OF NORTH AMERICA BY THE
END OF NEXT WEEK...AS ANOTHER UPPER LOW DEEPENS AND DIGS
SOUTHEASTWARD ACROSS THE GREAT LAKES AND MID-ATLANTIC REGION WHILE
A MID-LEVEL RIDGE BUILDS OVER THE CENTRAL PLAINS. THIS MAY ALLOW
YET ANOTHER SURGE OF COLD ARCTIC AIR TO INVADE SOUTH FLORIDA BY
THE END OF NEXT WEEK.



thank you "bearer of good news" ROFL!
Just what I wanted to hear.. more "Global Cooling"....

I remember when homes never used their heaters in South Florida..
the past few winters, we have used our heaters much more often than our A/C units...
Member Since: 29.08.2005 Posts: 294 Comments: 40840
708. ShenValleyFlyFish
16. joulukuuta 2010 klo 13:16 (GMT)
Snow beginning to fall in Page Co VA (home of world famous Luray Caverns) temp approximately 20F/-6.7C
Member Since: 9.09.2007 Posts: 36 Comments: 4687
707. IKE
16. joulukuuta 2010 klo 13:01 (GMT)
Quoting ShenValleyFlyFish:
Guitars: MADE IN USA


Stand back...stand back.....somebody give me a cheeseburger....


I see a yellow man, a brown man
A white man, a red man
Lookin' for Uncle Sam
To give you a helpin' hand
But everybody's kickin' sand
Even politicians
We're living in a plastic land
Somebody give me a hand, yeah


Member Since: 9.06.2005 Posts: 23 Comments: 37858
706. ShenValleyFlyFish
16. joulukuuta 2010 klo 12:25 (GMT)
Quoting IKE:
My 35,000th post on WU without one timeout. No wall of denial from me....

Guitars: MADE IN USA
Member Since: 9.09.2007 Posts: 36 Comments: 4687
705. ShenValleyFlyFish
16. joulukuuta 2010 klo 12:11 (GMT)
Quoting DontAnnoyMe:
Guitar: MADE IN USA
Member Since: 9.09.2007 Posts: 36 Comments: 4687
704. ShenValleyFlyFish
16. joulukuuta 2010 klo 12:06 (GMT)
Quoting Grothar:
Thought you might want to hear this from my adopted country.

Guitar: MADE IN USA
Member Since: 9.09.2007 Posts: 36 Comments: 4687
703. IKE
16. joulukuuta 2010 klo 11:59 (GMT)
Quoting hurristat:


great song, IKE


Guitar work is incredible. Think I'll take another listen:)
Member Since: 9.06.2005 Posts: 23 Comments: 37858
702. hurristat
16. joulukuuta 2010 klo 11:57 (GMT)
Quoting IKE:
My 35,000th post on WU without one timeout. No wall of denial from me....



great song, IKE
Member Since: 15.10.2008 Posts: 11 Comments: 2305
701. severstorm
16. joulukuuta 2010 klo 11:42 (GMT)

Morning Everyone, Another cold night in wcfl. Should be last nite i have to cover all the plants. Nice little warmup comming starting today.
Member Since: 25.11.2007 Posts: 0 Comments: 956
700. IKE
16. joulukuuta 2010 klo 11:03 (GMT)
My 35,000th post on WU without one timeout. No wall of denial from me....

Member Since: 9.06.2005 Posts: 23 Comments: 37858
699. IKE
16. joulukuuta 2010 klo 10:51 (GMT)
Quoting traumaboyy:


Good morning Ike!!

We are running about 10 behind you but headed the right direction finally!!


Morning. Temps west of me in Pensacola and Mobile near 60.

Member Since: 9.06.2005 Posts: 23 Comments: 37858
698. traumaboyy
16. joulukuuta 2010 klo 10:48 (GMT)
Quoting IKE:
Temp up to 52.7 at my location. My heater is getting a break.


Good morning Ike!!

We are running about 10 behind you but headed the right direction finally!!
Member Since: 18.08.2008 Posts: 0 Comments: 2263
697. IKE
16. joulukuuta 2010 klo 10:42 (GMT)
Temp up to 53.1 at my location. My heater is getting a break.
Member Since: 9.06.2005 Posts: 23 Comments: 37858
696. flsky
16. joulukuuta 2010 klo 10:10 (GMT)
Quoting PSLFLCaneVet:


Gotta give you credit for your perseverance. Keep on truckin.... And, thanks.
Member Since: 24.10.2006 Posts: 0 Comments: 1737
695. traumaboyy
16. joulukuuta 2010 klo 10:06 (GMT)
Quoting DontAnnoyMe:


LOL! Hey TB, here's some interesting early AM reading for you.

Link


Thanks!!
Member Since: 18.08.2008 Posts: 0 Comments: 2263

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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

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