Greenland experiences melting over 97% of its area in mid-July

By: Dr. Jeff Masters , 12:58 PM GMT on July 25, 2012

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Son Nghiem of NASA's Jet Propulsion Laboratory in Pasadena, CA, was analyzing radar data from the Indian Space Research Organization's Oceansat-2 satellite last week when he noticed that 97% of Greenland appeared to have undergone surface melting on July 12--an event completely unprecedented in 30 years of satellite measurements. In a July 24 press release from NASA, Nghiem said, "This was so extraordinary that at first I questioned the result: was this real or was it due to a data error?" Multiple satellite data sets confirmed the remarkable event, though. Melt maps derived from three different satellites showed that on July 8, about 40 percent of the ice sheet's surface had melted, as a strong ridge of high pressure set up over Greenland. By July 12, the melting had expanded to cover 97% of Greenland. As I blogged about last week, temperatures at at the top of the Greenland Ice Sheet, 10,551 feet (3216 meters) above sea level, and 415 miles (670 km) north of the Arctic Circle, had risen above the freezing mark four times in the 12-year span 2000 - 2011. But in mid-July 2012, temperatures eclipsed the freezing mark on five days, including four days in a row from July 11 - 14. Interestingly, ice core records show that in 1889, a similar pronounced melt event occurred at the top of the Greenland Ice Sheet, and such events occur naturally about every 150 years. "But if we continue to observe melting events like this in upcoming years, it will be worrisome," said Lora Koenig, a NASA/Goddard glaciologist and a member of the research team analyzing the satellite data. Such an event could occur as early as this weekend: the latest wunderground forecast for the Greenland Summit calls for above-freezing temperatures to return again by Saturday through Tuesday, with a high of 36°F (2°C) on Tuesday. This would come close to the record warm temperature at Summit of 3.6°C set just two weeks ago. Exceptionally warm temperatures in Greenland this July have been made more likely by the fact that Arctic sea ice area has been at record low levels so far this month. Furthermore, the Greenland Ice Sheet has become darker this July than at any point since satellite measurements began (Figure 2), allowing Greenland to absorb more solar energy and heat up.


Figure 1. Extent of surface melt over Greenland's ice sheet on July 8 (left) and July 12 (right). Measurements from three satellites showed that on July 8, about 40 percent of the ice sheet had undergone thawing at or near the surface. In just a few days, the melting had dramatically accelerated and an estimated 97 percent of the ice sheet surface had thawed by July 12. Image credit: NASA.



Figure 2. The albedo (reflectivity) of the Greenland Ice Sheet at its highest elevations (2,500 - 3,200 meters, or 8,200 - 10,500 feet) has steadily decreased in recent years as the ice has darkened due to increased melting and dark soot being deposited on the ice from air pollution. This July, the high elevations of Greenland were the darkest on record, which helped contribute to the record warm temperatures observed at the Greenland Summit. Image credit: Dr. Jason Box, Ohio State University.


Video 1. Melt water from the record July temperatures in Greenland fed the raging Watson River, which smashed two bridges connecting the north and south of Kangerlussuaq (Sønder Strømfjord), a small settlement in southwestern Greenland. The flow rate of 3.5 million liters/sec was almost double the previous record flow rate.

Greenland's Petermann Glacier
Greenland's glaciers have seen significant changes in recent years, as they respond to warmer air and water temperatures. Northwest Greenland's Petermann Glacier has seen two massive calving events in the past two years, though it is uncertain if these events were caused by the warming climate. The most recent event came on July 16, 2012, when the glacier calved a 46 square-mile iceberg two times the size of Manhattan. The same glacier calved an iceberg twice as big back on August 4, 2010--the largest iceberg observed in the Arctic since 1962. The freshwater stored in that ice island could have kept the Delaware or Hudson rivers flowing for more than two years, or kept all U.S. public tap water flowing for 120 days. According to a university press release by Andreas Muenchow, associate professor of physical ocean science and engineering at the University of Delaware's College of Earth, Ocean, and Environment, “While the size is not as spectacular as it was in 2010, the fact that it follows so closely to the 2010 event brings the glacier’s terminus to a location where it has not been for at least 150 years. Northwest Greenland and northeast Canada are warming more than five times faster than the rest of the world, but the observed warming is not proof that the diminishing ice shelf is caused by this, because air temperatures have little effect on this glacier; ocean temperatures do, and our ocean temperature time series are only five to eight years long — too short to establish a robust warming signal.”


Figure 3. The massive 46 square-mile iceberg two times the size of Manhattan that calved from Greenland's Petermann Glacier on July 16, 2012, as seen on July 21, 2012, using MODIS satellite imagery. Image credit: NASA.

Related posts
Record warmth at the top of the Greenland Ice Sheet (July 18, 2012)
Unprecedented May heat in Greenland; update on 2011 Greenland ice melt
Greenland update for 2010: record melting and a massive calving event

Jeff Masters

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. wxchaser97

some small cells poping up to the west of ya now



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Quoting KEEPEROFTHEGATE:
you do know anything past 144hrs on a model is totally useless right
Yeah but just posting the whole run.
Member Since: March 16, 2012 Posts: 127 Comments: 7928
Good night everyone...I'm off to bed!

Member Since: November 6, 2010 Posts: 11 Comments: 7881
384 hrs
Member Since: March 16, 2012 Posts: 127 Comments: 7928
I see the NE Caribbean gets some decent weather throughout the run! Hope it comes TRUE!! We need rain :) good nite folks
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Quoting wxchaser97:
348 hrs
you do know anything past 144hrs on a model is totally useless right
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Quoting KEEPEROFTHEGATE:
and lets throw in an increasing solar cycle for good measure



Looks like muzzle flash out of a gun.Hope that one is pointed away from us.
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348 hrs
Member Since: March 16, 2012 Posts: 127 Comments: 7928
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324 hrs
Member Since: March 16, 2012 Posts: 127 Comments: 7928
Quoting jrweatherman:
Instead of calling it Global Warming, we need to call it Global Cycles. Because that is what we are experiencing - a cycle of warm weather.


Well, you're entirely right. (Some people don't recognize that it's getting warming. Go figure.)

Now, next chore. Describe for us the reason why it's warming. Things don't just get hotter or colder "because they feel like it" or "it's something to do".

We need a physical reason....
Member Since: February 22, 2011 Posts: 0 Comments: 1344
288 hrs

Not much happened before
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and lets throw in an increasing solar cycle for good measure

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Quoting jrweatherman:
Instead of calling it Global Warming, we need to call it Global Cycles. Because that is what we are experiencing - a cycle of warm weather.


sorry but you are incorrect
its
global warming/climate change/climate shift


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Deleted
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192 hrs
Member Since: March 16, 2012 Posts: 127 Comments: 7928
Instead of calling it Global Warming, we need to call it Global Cycles. Because that is what we are experiencing - a cycle of warm weather.
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Quoting wxchaser97:
KEEPER what are your thoughts on the Detroit area for severe wx tonight.


stuff west of the windy city is what you have to watch
stuff over cen mich will traverse eastward overnight across south cen ont and slowly drift s se as warm front crosses the region

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Quoting NCHurricane2009:
Looks like my prediction that 98L wouldn't develop...written on my blog on Jul 24 4 AM...came true. The reasoning behind that is found in paragraph P3 of that post.

My post from yesterday morning (Jul 25 8 AMish) was a pain to get up. You can read the fully corrected version now...if anyone cares...

Working on the next post now...



Looks like you were right based on your post from July 24th at 4:00am.
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Member Since: August 2, 2010 Posts: 21 Comments: 9737
Member Since: August 2, 2010 Posts: 21 Comments: 9737
Member Since: August 2, 2010 Posts: 21 Comments: 9737
156 hrs
Member Since: March 16, 2012 Posts: 127 Comments: 7928
150 hrs, here comes the next wave
Member Since: March 16, 2012 Posts: 127 Comments: 7928
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Quoting KEEPEROFTHEGATE:
KEEPER what are your thoughts on the Detroit area for severe wx tonight.
Member Since: March 16, 2012 Posts: 127 Comments: 7928
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Looks like my prediction that 98L wouldn't develop...written on my blog on Jul 24 4 AM...came true. The reasoning behind that is found in paragraph P3 of that post.

My post from yesterday morning (Jul 25 8 AMish) was a pain to get up. You can read the fully corrected version now...if anyone cares...

Working on the next post now...

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126 hrs
Member Since: March 16, 2012 Posts: 127 Comments: 7928
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Member Since: November 6, 2010 Posts: 11 Comments: 7881
98L will be by Iceland pretty soon....amazing....lol
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SEVERE THUNDERSTORM WARNING
MIC017-111-145-260530-
/O.NEW.KDTX.SV.W.0095.120726T0355Z-120726T0530Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1155 PM EDT WED JUL 25 2012

THE NATIONAL WEATHER SERVICE IN DETROIT/PONTIAC HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
BAY COUNTY IN SOUTHEAST MICHIGAN...
MIDLAND COUNTY IN SOUTHEAST MICHIGAN...
SAGINAW COUNTY IN SOUTHEAST MICHIGAN...

* UNTIL 130 AM EDT

* AT 1153 PM EDT...DOPPLER RADAR INDICATED A LINE OF SEVERE
THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS OF 60
MPH. THESE STORMS WERE LOCATED ALONG A LINE EXTENDING FROM
EDENVILLE TO 13 MILES WEST OF ALMA...AND MOVING EAST AT 40 MPH.
PENNY SIZE HAIL MAY ALSO ACCOMPANY THESE DAMAGING WINDS.

* SEVERE THUNDERSTORMS WILL BE NEAR...
HOPE AROUND MIDNIGHT EDT.
SANFORD AND PLEASANT VALLEY AROUND 1205 AM EDT.
AVERILL AND BOMBAY AROUND 1210 AM EDT.
PORTER TOWNSHIP AND GORDONVILLE AROUND 1215 AM EDT.
CRUMP AND MIDLAND AROUND 1220 AM EDT.
WILLARD AND POSEYVILLE AROUND 1225 AM EDT.

THE WARNING INCLUDES AREAS SURROUNDING THESE LOCATIONS...
ZILWAUKEE... ST. CHARLES... SANFORD...
SAGINAW... PLEASANT VALLEY... PINCONNING...
OIL CITY... OAKLEY... MUNGER...
MIDLAND... MERRILL... MARION SPRINGS...
LINWOOD... KAWKAWLIN... FREELAND...
FRANKENMUTH... ESSEXVILLE... EDENVILLE...
COLEMAN... CHESANING... BRIDGEPORT...
BIRCH RUN... BENTLEY... BAY CITY...
AUBURN...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF
YOUR HOME OR BUSINESS.

&&

LAT...LON 4381 8461 4383 8417 4400 8416 4400 8405
4391 8403 4391 8391 4378 8392 4375 8395
4368 8392 4365 8386 4363 8374 4360 8370
4322 8369 4322 8393 4313 8393 4313 8437
4346 8438 4347 8461
TIME...MOT...LOC 0355Z 280DEG 34KT 4378 8442 4339 8489
WIND...HAIL 60MPH 0.75IN
Member Since: March 16, 2012 Posts: 127 Comments: 7928
114 hrs


Member Since: March 16, 2012 Posts: 127 Comments: 7928
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G'night yall!

Oh, how I love the South. ;)
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102 hrs, closed 1010 low at the lesser Antillies
Member Since: March 16, 2012 Posts: 127 Comments: 7928
Quoting Tribucanes:
Okay kids down stairs it's now dead on top of me less than an quarter mile from me now, if that. This storms got some strong circulation to it. Only on enough to message for now.


way to be a crybaby suckit up hope all is safe with you and your cats
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Quoting WxGeekVA:


Looking at that map...



Night folks!

Have a good night Wx!
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96 hrs
Member Since: March 16, 2012 Posts: 127 Comments: 7928
Quoting nigel20:
Quite a bit SAL over the eastern Caribbean


Looking at that map...



Night folks!
Member Since: September 3, 2011 Posts: 13 Comments: 3468
78 hrs
Member Since: March 16, 2012 Posts: 127 Comments: 7928
Quite a bit SAL over the eastern Caribbean
Member Since: November 6, 2010 Posts: 11 Comments: 7881
Quoting BobWallace:


Have you seen any recent CO2 data for the South Pole? I find nothing more recent than Dec 2010.

Recently CO2 in the Arctic was measured at 400ppm, higher than what we're seeing at Mauna Loa. I'm wondering if the CO2 level might be lower at the south end.


I think that most of the attention is currently focused on the arctic. The dramatic recent events in Greenland are causing scientists worldwide to concentrate on understanding the global impact of these events.

Not that what is happening in Antarctica in inconsequential because we know it is warming and shedding mass, just not at the rate of Greenland and the Arctic Ocean. Also, the vast majority of the world's population resides in the Northern Hemisphere and are most vulnerable to the extreme weather events caused by changes in the arctic regions.
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Not much at 60, 66, 72 hours
Member Since: March 16, 2012 Posts: 127 Comments: 7928
SEVERE THUNDERSTORM WARNING
MIC057-073-107-117-260500-
/O.NEW.KGRR.SV.W.0055.120726T0340Z-120726T0500Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
1140 PM EDT WED JUL 25 2012

THE NATIONAL WEATHER SERVICE IN GRAND RAPIDS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
GRATIOT COUNTY IN CENTRAL MICHIGAN...
ISABELLA COUNTY IN CENTRAL MICHIGAN...
SOUTHEASTERN MECOSTA COUNTY IN CENTRAL MICHIGAN...
MONTCALM COUNTY IN CENTRAL MICHIGAN...

* UNTIL 100 AM EDT

* AT 1135 PM EDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE
TRACKING A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING
DAMAGING WINDS IN EXCESS OF 60 MPH. THESE STORMS WERE LOCATED
ALONG A LINE EXTENDING FROM CLARE TO 10 MILES WEST OF MOUNT
PLEASANT TO 5 MILES SOUTHEAST OF HOWARD CITY..AND MOVING EAST AT
45 MPH.
SMALL HAIL MAY ALSO ACCOMPANY THESE DAMAGING WINDS.

* LOCATIONS IMPACTED INCLUDE...
HOWARD CITY... GREENVILLE... MOUNT PLEASANT...
ALMA... EDMORE... STANTON...
ROSEBUSH... ASHLEY... ITHACA...
FERRIS TWP... LANGSTON... CEDAR LAKE...
VICKERYVILLE... BUTTERNUT... FENWICK...
TURK LAKE... SIDNEY... CORAL...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS CAN PRODUCE DAMAGING WIND IN EXCESS OF 60 MILES
PER HOUR...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN.
FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF
YOUR HOME OR BUSINESS. HEAVY RAINS FLOOD ROADS QUICKLY SO DO NOT
DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.

TO REPORT SEVERE WEATHER...CONTACT THE NATIONAL WEATHER SERVICE IN
GRAND RAPIDS AT 1 800 647 3836.

&&

LAT...LON 4312 8531 4329 8531 4330 8556 4347 8556
4347 8524 4359 8501 4382 8486 4381 8460
4347 8460 4347 8436 4312 8436
TIME...MOT...LOC 0340Z 285DEG 38KT 4378 8471 4356 8486
4331 8532
WIND...HAIL 60MPH <1.00IN

$$

OSTUNO
Member Since: March 16, 2012 Posts: 127 Comments: 7928
48 hrs and still not much
Member Since: March 16, 2012 Posts: 127 Comments: 7928
42 hrs and not much with the wave so far
Member Since: March 16, 2012 Posts: 127 Comments: 7928

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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.