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

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

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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Quoting ProgressivePulse:
Hope all are safe up in the Great Lakes tonight, big storms rolling in.

Could be getting rather active in the Atlantic next month. Very strong MJO pulse is forecast to persist for the month according to the EWP. I'm not even going to bring up the steering ATM but to say that hopefully the change in MJO brings some change in the pressure means.

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Quoting Tribucanes:
See you all tomorrow have a good early morning. wxchaser97 your a WU junkie (like me) and a real trooper to still be here. :) Enjoy your storms, hope all stay safe.
Dont you mean later in the day:) Thanks, its been hard but new faith has came, storms firing off to the west. See ya later. Slamguitar we all need the rain here, hope you get yours.
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Getting a brief downpour and additional storms are possible.
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See you all tomorrow have a good early morning. wxchaser97 your a WU junkie (like me) and a real trooper to still be here. :) Enjoy your storms, hope all stay safe.
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Also notice how the wave stalls out in the last 3 frames. Strong pulses like that are hard to bust sometimes. Could linger into a good part of September as well.
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Thunderstorms kicking up in my corner of the state and it's starting to fill in. Need some nice downpours.

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7400 or so without power in Wisconsin right now. FireWeather161 NYC is really under the gun. The worst is going to hit there quite possibly. Highest potential for severe wind, hail, and tornadoes is in NY. As bad as it gets excluding a tornado outbreak quite possibly for NYC tomorrow.
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Hope all are safe up in the Great Lakes tonight, big storms rolling in.

Could be getting rather active in the Atlantic next month. Very strong MJO pulse is forecast to persist for the month according to the EWP. I'm not even going to bring up the steering ATM but to say that hopefully the change in MJO brings some change in the pressure means.

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Motor City Madhouse Ted Nugent
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Quoting Tribucanes:
Well their update only got worse for ya in most ways FireWeather161. Five percent tornado chance is not that bad, let's hope it stays at that. Lot's of us having a bad night tonight weather wise too. Although my warned storm has been hitting me now for the last five and I've gotten a twenty second 40mph gust and torrential rain. So much for severe. Good luck tomorrow FireWeather161.
Thats how it always goes my friend.
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So like Feb 10 would be peak
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Well their update only got worse for ya in most ways FireWeather161. Five percent tornado chance is not that bad, let's hope it stays at that. Lot's of us having a bad night tonight weather wise too. Although my warned storm has been hitting me now for the last five and I've gotten a twenty second 40mph gust and torrential rain. So much for severe. Good luck tomorrow FireWeather161.
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I know, don't consider you a kid. :) Most the teenagers here are grown up for modern day kids. Kids are so soft in America these days though, most wouldn't have made it 100 years ago.
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Latest update is out, we have a 5% Tornado area here in Greater NY, and this pretty impressive wind threat area. Should be very interesting tomorrow.
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Quoting Tribucanes:
Aussie I'm only on enough to read these few comments and then give a quick update. But you are ABSOLUTELY right. All the kiddies are in bed though, setting a bad example though if they were here.
Im a teen but I was told I could stay up.
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1021. KEEPEROFTHEGATE (Mod)


getting hammer here
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With the last big Greenland ice sheet melt of 1889, we have another possible analog year to ponder. The actual number of tropical systems is probably wrong due to a lack of modern technology, but note how like 1934(record July Midwest heat) and 1985(very active July Eastern Pacific,) the tracks seem to favor less recurvature.

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Outflow boundary almost on me about a mile or 2 north.
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Aussie I'm only on enough to read these few comments and then give a quick update. But you are ABSOLUTELY right. All the kiddies are in bed though, setting a bad example though if they were here.
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Large barn down, power lines and trees down, power outages. Winds that blew the barn they showed down had to be a 100+gust. Wow. Large solid build barns down just blow down in a 70 mph gust usually. No large scale damage reports yet though. All the above mentioned were isolated for the most part. About 700 without power in Madison, Wisconsin.
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Quoting HurricaneHunterJoe:
Hey Aussie? When is it likliest for a Tropical Cyclone hitting the north coast? How about the east coast?

You mean, when is our Tropical Cyclone season?

The Australian cyclone season officially runs from November to April, although very few have occurred in November.

The earliest cyclone to impact the northwest Australian coast in the season was on 19 November 1910 when the eye passed over Broome. One of the latest cyclones in a season was TC Herbie that formed near Cocos Islands and passed over Shark Bay on 21 May 1988.
Member Since: September 30, 2007 Posts: 9 Comments: 16036
I was guessing December for the North
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The NWS says a hit around 2:25-2:30am with 60mph+ winds and penny size hail.
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More like 10 min. Heart of the winds are coming straight through where I'm at soon, or so my Met. says.
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Quoting Tribucanes:
Warning is back. Confirmed 70mph winds again. Severe will be here in five or so now.


WE REPEAT FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF
YOUR HOME NOT ON YOUR PC/LAPTOP ON A WEATHER BLOG.
Member Since: September 30, 2007 Posts: 9 Comments: 16036
Hey Aussie? When is it likliest for a Tropical Cyclone hitting the north coast? How about the east coast? Of course the coast's of Australia!
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Warning is back. Confirmed 70mph winds again. Severe will be here in five or so now.
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Im staying till the bitter end
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The outflow boundary is intensifying any storm it hits for me. Im not in the clear.
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LMAO Aussie my warning's been dropped but it's still going to be nasty here soon.
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Quoting wxchaser97:


FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF
YOUR HOME, NOT ON YOUR PC/LAPTOP ON A WEATHER BLOG.
Member Since: September 30, 2007 Posts: 9 Comments: 16036


Only thing GFS sees is a Typhoon by Okinawa.It follows a disturbance from Africa and loses it near the Bahamas.
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You've got me by two dew points and two degrees. Dastardly.
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Quoting Tribucanes:
Dewpoint here 73 now humidity 100 incoming

Temp of 84 and dew point of 75
Storms northwest are going severe and Im offically under a warning.
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Dewpoint here 73 now humidity 100 incoming
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Under a severe thunderstorm warning, I may now take a direct hit.
SEVERE THUNDERSTORM WARNING
MIC099-125-147-260700-
/O.NEW.KDTX.SV.W.0100.120726T0537Z-120726T0700Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
137 AM EDT THU JUL 26 2012

THE NATIONAL WEATHER SERVICE IN DETROIT/PONTIAC HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
MACOMB COUNTY IN SOUTHEAST MICHIGAN...
OAKLAND COUNTY IN SOUTHEAST MICHIGAN...
SOUTHERN ST. CLAIR COUNTY IN SOUTHEAST MICHIGAN...

* UNTIL 300 AM EDT

* AT 136 AM 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 CAPAC
TO GRAND BLANC...AND MOVING SOUTHEAST AT 45 MPH. PENNY SIZE HAIL
MAY ALSO ACCOMPANY THESE DAMAGING WINDS.

* SEVERE THUNDERSTORMS WILL BE NEAR...
EMMETT AND HIGHLAND AROUND 145 AM EDT.
GOODELLS AND WHITE LAKE AROUND 150 AM EDT.
SMITHS CREEK AND WOLVERINE LAKE AROUND 155 AM EDT.
WEST BLOOMFIELD AND SYLVAN LAKE AROUND 200 AM EDT.
MARYSVILLE AND FRANKLIN AROUND 205 AM EDT.
LATHRUP VILLAGE AND BEVERLY HILLS AROUND 210 AM EDT.

THE WARNING INCLUDES AREAS SURROUNDING THESE LOCATIONS...
WEST BLOOMFIELD... WARREN... TROY...
STERLING HEIGHTS... ST. CLAIR SHORES... ST. CLAIR...
SOUTHFIELD... ROYAL OAK... ROMEO...
ROCHESTER... RICHMOND... PONTIAC...
OXFORD... ORTONVILLE... NEW BALTIMORE...
MOUNT CLEMENS... MEMPHIS... MARYSVILLE...
MARINE CITY... MACOMB TOWNSHIP... HOLLY...
HARSENS ISLAND... EMMETT... CLARKSTON...
CAPAC... BIRMINGHAM... ARMADA...
ALGONAC...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4288 8247 4279 8246 4261 8251 4252 8269
4256 8266 4256 8270 4259 8267 4260 8272
4267 8263 4268 8269 4265 8280 4256 8277
4254 8285 4245 8286 4244 8342 4270 8369
4287 8369 4289 8299 4308 8299 4296 8242
TIME...MOT...LOC 0537Z 297DEG 43KT 4301 8289 4291 8361
WIND...HAIL 60MPH 0.75IN
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Quoting Tribucanes:
Yup, my area is severe warned currently but it has weakened in the last fifteen. Going to take a look at what your about to get.
Im in SE Oakland county, storms N and NW and should eventually get something.
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I don't know wxchaser those puppies to your West have quite a ways to go to get to severe level. Nothing North of you is going to impact to you since it's moving Eastward. But they did just pop up, just really weird to see storms firing and strengthening at night. By no means unprecedented though.
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Greenland melts before NASA's eyes

The Greenland ice sheet is melting at an ''unprecedented'' rate, according to NASA satellite data that shows 97 per cent of the vast mass is undergoing some form of melting.
''This was so extraordinary that at first I questioned the result: Was this real or was it due to a data error?'' a NASA researcher, Son Nghiem, said.
About half of the ice sheet usually shows signs of melting in a northern hemisphere summer, but the satellite data shows that between July 8 and July 12 the melt extended to cover almost all of Greenland.
It follows the breaking off this month of a giant chunk of ice from Greenland's Petermann Glacier. This formed an iceberg about twice the size of Manhattan, about 120 square kilometres in area.
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''For several days this month, Greenland's surface ice cover melted over a larger area than at any time in more than 30 years of satellite observations,'' NASA researchers said in a statement.
''Nearly the entire ice cover of Greenland, from its thin, low-lying coastal edges to its two-mile [3.2-kilometre] thick centre, experienced some degree of melting at its surface, according to measurements from three independent satellites analysed by NASA and university scientists.''
They described the event as being without precedent, because such a massive loss of ice has not been observed by humans, although estimates derived from studying old, compressed ice suggest that melts on this scale happen about once every 150 years.
''Researchers have not yet determined whether this extensive melt event will affect the overall volume of ice loss this summer and contribute to sea-level rise,'' NASA said. ''About one-fifth of the annual sea-level rise experienced globally is attributed to the melting of the ice sheet.''
The manager of Australia's climate monitoring section at the Bureau of Meteorology, Karl Braganza, said the observation was a disturbing development.
''In terms of just one event taken in isolation, you can't tell much from it. We had a similar event back in the 1800s so it does happen from time to time,'' Dr Braganza said.
''But clearly there is a trend going on in the Arctic this century. We have warmer ocean temperatures, now what looks like particularly large reductions in sea ice, and large chunks of glaciers breaking off.''
The Arctic appeared to be locked in a vicious cycle, where rising concentrations of greenhouse gases meant higher temperatures, and more melting ice, which meant, in turn, that less of the sun's incoming heat was reflected away from the Earth.
''What's alarming to scientists is that we know the Arctic ice is a key feedback, and the warming in the Arctic has been slightly faster than was predicted 10 or 20 years ago,'' Dr Braganza said.
''This year, we measured CO2 emissions in the Arctic at above 400 parts per million for the first time. That's the first time it's been at that level in 3 million years. Back then, during the Pliocene period, the Greenland ice sheet wasn't a feature. Now we've taken the atmospheric chemistry back to that territory.''
The NASA statement said the huge melt had been driven by an unusual ''heat dome'' of relatively warm air that travelled across Greenland this month. The warm patch spiked just before July 18, and has now dissipated, they said.
Member Since: September 30, 2007 Posts: 9 Comments: 16036
Yup, I saw what Keeper posted with those pop ups to your west. My area is severe warned currently but it has weakened in the last fifteen. Going to take a look at what your about to get.
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Storms develooping all around me and one just to the north of me. I may be under severe warning soon.
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wxchaser 97 looks like your going to get you severe weather. Keeper's great with the tools of the trade. Thanks Keeper.
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Going to finally get my first legitimate severe storm of the year tonight in about 20/30. Three to five miles in front of the storm, winds confirmed by law enforcement at 55-70. Shouldn't be too bad though, I think it's peaked for now at least. Hope it's not recycling.
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Quoting sunlinepr:


It's a very complex landing procedure.... Hope it goes OK....


Yes,I think they lost 2 missions.Very very complicated.
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To clear it up earlier, I live in SE Columbia county in Wisconsin. Wicked lightening and just as I suspected it went severe just North and East of here. Hope the next line which is producing 70 winds and traveling at 50mph continues to go NE and misses me. Wouldn't be surprised if it goes more Eastward soon though, which would put me in it. Lightening got so severe I unplugged the AC and turned off the computer. When I took out the internet card, lightening struck close by at the same time. I got a nasty little shock and had to drop it. No boom or anything. Didn't strike anything, weird. Rotation detected now in these storms on the way. This is still intensifying. Environment is ripe to produce one tonight I think too.
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Quoting HurricaneHunterJoe:


Big Rover scheduled to land August 5,2012 10:32pm Pacific Time. It's about 2 million miles from Mars right now. I think they will have live coverage on the Science Channel.


It's a very complex landing procedure.... Hope it goes OK....
Member Since: August 2, 2010 Posts: 22 Comments: 10147
Quoting KEEPEROFTHEGATE:
. wxchaser97

some small cells poping up to the west of ya now



Those are rapily developing and could go severe. I still have a chance at storms.
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Big Rover scheduled to land August 5,2012 10:32pm Pacific Time. It's about 2 million miles from Mars right now. I think they will have live coverage on the Science Channel.
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. wxchaser97

some small cells poping up to the west of ya now



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Dr. Masters co-founded wunderground in 1995. He flew with the NOAA Hurricane Hunters from 1986-1990. Co-blogging with him: Bob Henson, @bhensonweather

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