Satellites reveal rare levels of Greenland ice melt
Satellite data show Greenland surface melt on July 8, left, and July 12. "Melt" is dark pink; "probable melt" is light pink.
July 25th, 2012
12:40 PM ET

Satellites reveal rare levels of Greenland ice melt

Nearly all of Greenland’s ice cover at least temporarily melted at the surface during an unusually warm stretch in mid-July - a level of melting not seen there in 123 years, NASA said.

In an average summer, melting happens on about half of the surface of Greenland’s ice sheet, which covers most of the land and is an average 1 mile thick.

But an unusually strong ridge of relatively warm air - hovering just above freezing for several hours at the highest elevation - rapidly accelerated melting this month, and satellites showed that an estimated 97% of the surface had melted at some point by July 12, NASA said.

While some of that melt water freezes in place, some of it is lost to rivers and the ocean – and mid-July’s melting caused river flooding that threatened a number of bridges, said Tom Wagner, NASA’s cryosphere program manager in Washington. (The flooding has been captured on a number of YouTube videos, including this one.)

Where this falls in the larger context of Greenland’s changing ice cap - scientists say it is shrinking and causing ocean levels to rise, with warming ocean waters causing ice on the periphery to be lost through melting and rapid flow - is a complicated question, NASA says.

Ice core samples show that the surface melting seen this July happens once in about every 150 years, and the last such melt happened in 1889, NASA said.

“It could be that this melt event is caused by normal variations that just happen once in a while,” Wagner said by phone Tuesday.

So, Wagner said, one can’t attribute July’s melting to global warming, but the melting must be digested with this in mind: that "warming is causing the loss of ice all over Greenland, and the Greenland ice sheet is shrinking."

Wagner said Greenland has lost 150 gigatons of ice per year over the last 20 years, and its shrinking cap contributes up to half a millimeter a year to global sea-level rise. Researchers haven’t determined how much of mid-July’s melt refroze or went into the ocean, NASA said.

The July 8-12 melting happened days before an island of ice twice the size of Manhattan broke off from Greenland’s Petermann Glacier on July 16. But with glacier calving attributed to ocean temperature, not the more quickly fluctuating air temperature, no one is linking the calving to July’s melting of surface ice, Wagner said.

July’s melting "combined with other natural but uncommon phenomena, such as the large calving event last week on Petermann Glacier, are part of a complex story,” Wagner said in a news release. “Satellite observations are helping us understand how events like these may relate to one another as well as to the broader climate system.”

July’s melting was detected by three satellites - the Indian Space Research Organization’s Oceansat-2, and NASA’s Terra and Aqua.

July 18, 2012: Massive ice island breaks off Greenland glacier

May 4, 2012: Greenland ice melt could raise seas less than feared, study says

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Filed under: Greenland • Science • Weather
soundoff (263 Responses)
  1. ofCanada

    We are so screwed.

    July 25, 2012 at 8:04 pm | Report abuse |
  2. Amargosa

    It was hotter back in 1930's then it is now.

    July 25, 2012 at 8:05 pm | Report abuse |
  3. Mark

    It would take less than 7 feet of new snow pack a year to reach a mile in 800 years...reasonable in a cooling cycle.

    July 25, 2012 at 8:19 pm | Report abuse |
  4. Semantics101

    The Earth was warmer a 1000 yrs ago. Then there was a mini-ice age for a few hundreds years. Grain crops died in Europe and people starved until the potatoe was discovered by the Spanish in South America.

    These occurences are beyond control, we can only avoid catastrophy. Humans are as far as I know the most intelliegent beings to exist on the planet. However like any animal if we can't use our adaptive skills for survival then we're fossils.

    July 25, 2012 at 8:20 pm | Report abuse |
  5. David

    Global warming is not real, cutting taxes creates jobs, gun control does not good.....

    July 25, 2012 at 8:26 pm | Report abuse |
  6. carbide scribe

    Increased fresh water decreases the oceans salinity. As the pockets of salt, deep underwater, off the east coast, are removed. So too will the gulf stream change. The changing ocean currents will bring on the next ice age.
    Enjoy the heat while you can.
    Also, this may be a good time to speculate on Greenland real estate.

    July 25, 2012 at 9:14 pm | Report abuse |
    • phunk

      I am a firm believer in climate change occuring but seriously? We all saw The Day After Tomorrow also buddy, it was just a movie and that's not what's actually occuring.

      July 26, 2012 at 12:54 am | Report abuse |
    • FalcoPr

      Correct. The entire conveyor belt connecting the shallow currants and deep sea currants are disrupted. These currants can take up to 1000 years to complete from the top to the bottom and back.

      July 26, 2012 at 3:45 am | Report abuse |
    • lunchbreaker

      FYI, "The Day after Tomorrow" was based on a book called "The Coming Global Superstorm" which was co-authored by one person who produces television shows about psychics and aliens and another guy who wrote an autobiography of his own alien abduction.

      July 26, 2012 at 8:57 am | Report abuse |
    • Nico

      the next ice age....for Britain. The rest of us will have 110 degree summers

      July 27, 2012 at 8:55 am | Report abuse |
  7. FalcoPr

    The Flat-Earth Republicans will try to kill these facts with their massive support from corporate America.

    July 26, 2012 at 3:40 am | Report abuse |
    • normsw

      Flat earth Republicans? Haha. How about the pie-in-the-sky Democrats pointing the finger everywhere but at the real problem?

      July 26, 2012 at 5:12 am | Report abuse |
    • phunk

      No normsw, we point it at the real problem: conservatives.

      July 26, 2012 at 5:46 am | Report abuse |
    • s kel

      See thats why we can get nothing done. Proff is shown about this polor region melting and what does a typical consertive mind like normsw does? They try to somehow divert deny,divert, destroy, or belittle what is in front of them! Thats why nothing helpful gets done.Its mostly due to right wing ignorance, meaness and greed.

      July 26, 2012 at 12:00 pm | Report abuse |
    • Brineybones

      Talk about conspiracy theorists... You provide a textbook case. Do you see EVERYTHING 180 degrees off?

      July 27, 2012 at 9:00 pm | Report abuse |
    • Steve

      It happened before in 1889. Did our cars and power plants cause it then as well? Oh wait!

      July 31, 2012 at 10:22 pm | Report abuse |
  8. normsw

    Just as I thought; ice core samples show that Greenland has experienced multiple cycles of freezing and melting over the millenia. Anyone who thinks othewise is either ignorant or misinformed. Let's leave the deductions to the scientists and give up our layman's uneducated opinions.

    July 26, 2012 at 4:58 am | Report abuse |
  9. normsw

    All of the smokestacks & exhaust pipes worldwide are nothing when compared to the constant output of the world's volcanoes combined with total animal flatulance and natural gas emissions exiting the ground. Get a grip, global warmingers!

    July 26, 2012 at 5:26 am | Report abuse |
    • Thermion7

      Terrence Gerlach of the Cascades Volcano Observatory (USGS) – Crunched the numbers on this I believe his paper was published in 2007. "... – researchers estimate between 0.13 and 0.44 billion metric tons are released by volcanoes each year, with their best estimates between 0.15 and 0.26 billion tons – even the highest end of the range is dwarfed by anthropogenic emissions of 35 billion tonnes..." 135 times the volcanic output

      July 27, 2012 at 12:11 pm | Report abuse |
    • Thermion7

      Dr Marie Edmonds, a volcanologist at Cambridge University agrees. While volcanoes are the most important natural source of atmospheric CO2, she notes, "The results show clearly that the amount is 100 to 150 times less than anthropogenic amounts."

      July 27, 2012 at 12:13 pm | Report abuse |
  10. child of midian

    We conservatives support pollution. First we need to not only bring "smog" back to LA we need to cover the entire planet in it, next we need to knock down every, single, mountain everywhere and burn all the coal we can get our hands on, lift all regulation and oversight so that industry can pollute and poison all it wants in the name of capitalism and hope someday all our rivers and streams can be set on fire. Furthermore we will not abide by scientific data detailing how CO2 in the atmosphere directly correlates to climate temperatures or all this desalinization of the ocean BS, no matter how many times you check it and see that it's in fact less saturated with salt due to fresh water melt. Above all we call all you liberal anti-capitalist, socialist dummies who are so stupid you're pushing an agenda for clean air and water and to slow climate change and not making a single dime of profit off it.

    July 26, 2012 at 9:50 am | Report abuse |
  11. Barry G.

    This does not look good.

    July 26, 2012 at 11:49 am | Report abuse |
  12. Barry G.

    How hot and how bad will conditions have to become, before conservatives admit they were wrong?

    July 26, 2012 at 11:50 am | Report abuse |
    • william english

      200ft rise of oceans

      July 26, 2012 at 2:45 pm | Report abuse |
    • peter

      Not till the last one has died... and something tells me they would survive a nuclear war somehow, along with the cocroaches.

      July 26, 2012 at 7:25 pm | Report abuse |
  13. J.C.

    What happened in 1889? Horse flatulence?

    July 26, 2012 at 12:44 pm | Report abuse |
  14. william english

    the ice melts excess water puts preasure on the pacific plate pushing it down which in turn causing earth quakes and pushes magma up volcanoes erupt putting ash in the air thus cooling earth making excess snow and ice.
    that's the circle that's a fact

    July 26, 2012 at 2:35 pm | Report abuse |
  15. sonic10158

    even if conservatives didn't exist, the problem still would. EVERYONE (liberal and conservative) including Al Gore are guilty of causing this in some way or another, whether by using a gas powered car, buying plastic products, etc.

    July 27, 2012 at 1:04 am | Report abuse |
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