Climate

ABC News On Stunning Greenland Ice Melt: ‘Scientists Say They’ve Never Seen Anything Like This Before’

NASA reported today some truly shocking findings on the melting of the Greenland ice sheet this summer:

Satellites See Unprecedented Greenland Ice Sheet Surface Melt

July 24, 2012: 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. Nearly the entire ice cover of Greenland, from its thin, low-lying coastal edges to its two-mile-thick center, experienced some degree of melting at its surface, according to measurements from three independent satellites analyzed by NASA and university scientists.

On average in the summer, about half of the surface of Greenland’s ice sheet naturally melts. At high elevations, most of that melt water quickly refreezes in place. Near the coast, some of the melt water is retained by the ice sheet and the rest is lost to the ocean. But this year the extent of ice melting at or near the surface jumped dramatically. According to satellite data, an estimated 97 percent of the ice sheet surface thawed at some point in mid-July.

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.

We reported last month on the “Unprecedented May Heat In Greenland,” where the temperature hit 76.6°F. So it would seem that unprecedented heat leads to unprecedented melting.

I saw the ABC News story tonight, which had the headline quote. I’ll post the video when it is online.

The NASA release has more detail:

Son Nghiem of NASA’s Jet Propulsion Laboratory in Pasadena, Calif., was analyzing radar data from the Indian Space Research Organisation’s (ISRO) Oceansat-2 satellite last week when he noticed that most of Greenland appeared to have undergone surface melting on July 12. Nghiem said, “This was so extraordinary that at first I questioned the result: was this real or was it due to a data error?”

Nghiem consulted with Dorothy Hall at NASA’s Goddard Space Flight Center in Greenbelt, Md. Hall studies the surface temperature of Greenland using the Moderate-resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra and Aqua satellites. She confirmed that MODIS showed unusually high temperatures and that melt was extensive over the ice sheet surface.

Thomas Mote, a climatologist at the University of Georgia, Athens, Ga; and Marco Tedesco of City University of New York also confirmed the melt seen by Oceansat-2 and MODIS with passive-microwave satellite data from the Special Sensor Microwave Imager/Sounder on a U.S. Air Force meteorological satellite.

The melting spread quickly. Melt maps derived from the three satellites showed that on July 8, about 40 percent of the ice sheet’s surface had melted. By July 12, 97 percent had melted.

This extreme melt event coincided with an unusually strong ridge of warm air, or a heat dome, over Greenland. The ridge was one of a series that has dominated Greenland’s weather since the end of May. “Each successive ridge has been stronger than the previous one,” said Mote. This latest heat dome started to move over Greenland on July 8, and then parked itself over the ice sheet about three days later. By July 16, it had begun to dissipate.

Even the area around Summit Station in central Greenland, which at 2 miles above sea level is near the highest point of the ice sheet, showed signs of melting. Such pronounced melting at Summit and across the ice sheet has not occurred since 1889, according to ice cores. . . .

Ice cores from Summit show that melting events of this type occur about once every 150 years on average. With the last one happening in 1889, this event is right on time,” says Lora Koenig, a Goddard glaciologist and a member of the research team analyzing the satellite data. “But if we continue to observe melting events like this in upcoming years, it will be worrisome.”

That statement is a classic example of what James Hansen called “scientific reticence.”

The scientific literature and recent observations — along with our ongoing lack of climate action — have long passed the worrisome stage (see the post last month “Greenland Ice Sheet Melt Nearing Critical ‘Tipping Point’ ” and links below).

Neven’s Arctic Sea Ice blog notes that “In the meantime Dr. Jason Box reports on the Meltfactor blog“:

Greenland ice sheet record surface melting underway

While the potential impact of wildfires on darkening the Greenland ice sheet surface remain to be resolved, there is mounting evidence of an extreme year 2012 melt.

Melt signatures from active microwave remote sensing are stronger than in recent years over the upper areas of the ice sheet. Dark areas indicate absorption of the microwave signal emitted by the satellite. While, year 2010 and 2011 are recognized as being record melt years (Tedesco et al. 2011, van As et al. 2011), year 2012 melting appears to be more extensive.

Greenland_ASCAT_melt_2010-2012

… In my recently accepted albedo paper (Box et al. 2012, ACCEPTED VERSION), see abstract, the statement: “it is reasonable to expect 100% melt area over the ice sheet within another similar decade of warming.” [May be coming true already.]

Neven also directs us to ScienceDaily, which reports:

Surprising Link Between Ice and Atmosphere: GPS Can Now Measure Ice Melt, Change in Greenland Over Months Rather Than Years

ScienceDaily (July 24, 2012) — Researchers have found a way to use GPS to measure short-term changes in the rate of ice loss on Greenland — and reveal a surprising link between the ice and the atmosphere above it

The study, published in the early online edition of the Proceedings of the National Academy of Sciences, hints at the potential for GPS to detect many consequences of climate change, including ice loss, the uplift of bedrock, changes in air pressure — and perhaps even sea level rise.

The team, led by earth scientists at Ohio State University, pinpointed a period in 2010 when high temperatures caused the natural ice flow out to sea to suddenly accelerate, and 100 billion tons of ice melted away from the continent in only 6 months. . . .

Is it worrisome yet?

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29 Responses to ABC News On Stunning Greenland Ice Melt: ‘Scientists Say They’ve Never Seen Anything Like This Before’

  1. Ron Graves says:

    It seems to me that the ice loss in the graphic at the top of the page is considerably at odds with that of the July 18 2012 satellite image.

  2. Jack Burton says:

    One could say that this has happened before and Greenland was due for such a melting event.
    So, we can take comfort in that. But, this warm event is taking place in the face of years of increasing ice melt in Greenland. So if this is a natural event, then it is being grafted onto an unnatural warming and melting of Greenland’s climate and ice cover.
    We need more time to know how serious this is, but taken in the context of extreme weather all over the place, it may fit in as just one more wild extreme that an unstable warming climate is throwing at us. Are we shifting to a new state of climate, is that what all the wild weather means, a radical shift underway.
    If I had to guess, I would say YES, I think we have crossed a tipping point, maybe not as radical a tipping point as could be coming in 50 years, but a tipping point nevertheless!

  3. Samuel says:

    To paraphrase the latest Batman movie…it is not “A Storm’s Coming” but rather “The Storm is Now.”

  4. Leif says:

    Note how the current year big dip in ice melt happened a full month before the last record. I am not sure if that means much but it raises my eye brows. http://nsidc.org/arcticseaicenews/

  5. Merrelyn Emery says:

    Anybody who doesn’t believe that systemic change can happen at fantastic speed is about to get a dramatic education, ME

  6. prokaryotes says:

    Research closes gap between warming and Co2 rise

    I cannot emphasize enough how important this result is,” he said. “The authors collapse these values to something so short that it has major implications for our understanding of the carbon cycle and climate change.” http://climateprogress.net/climate-science/item/research-closes-gap-between-warming-and-co2-rise.html

  7. A billion [tons] here, a billion [tons] there, and soon you’re talking real [ice loss].

  8. Absolutely. This isn’t just about Greenland’s ice. It’s about the jet stream, the polar ice cap, the arctic ocean, thawing permafrost — the whole northern cap of the world which is warming faster than the temperate or tropical regions. A change in one element, say the melting of the polar ice cap, effects change in other elements in a series of multi-level, synergetic feedbacks that can bring the whole region — no, the whole planet down.

    Scary stuff, and way ahead of “schedule.”

  9. Salvi says:

    I think the first graph shows everywhere that experienced melting. I don’t think It is showing that it was all melted. There is still ice there (shown in the satellite image) but it experienced melting at the surface.
    from BBC news: “Nasa said that nearly the entire ice cover of Greenland, from its thin, low-lying coastal edges to its centre, which is 3km (two miles) thick, experienced some degree of melting at its surface.”

  10. Craig D says:

    North Carolina has outlawed GW. So, this report must be fake — dreamed up by some sinister cabal of greedy scientists so they could spend their summers vacationing in remote desolate god forsaken places. While we are struggling with our lattes from Starbucks, they are eating haute cuisine of canned soup heated over a small portable propane camping stove in some small cheap tent. Their efforts to live in such idyllic ways knows no bounds. Knowing this, how can we believe these reports. Sorry, my time is up, have to put my head back into the sand bucket. If my head is out of the sand bucket for too long, I might accidentally learn something. And that makes my head hurt.

  11. Craig D says:

    By definition a tipping point is a point that once passed there is no going back. So, if we passed the tipping point now, there will be no worse tipping point by 2050. The climate regime will have already tipped.

    The real clue that we have passed the tipping point is that kilometer wide plumes of methane have been witnessed coming from the bottom of the East Siberian Sea. (see Similitov, 12/2011.)

  12. D. R. Tucker says:

    “By abandoning President Carter’s commitment to clean energy, and by allowing the denialist right to dominate the airwaves millions of Americans trust, Reagan set us on the course to have a rendezvous with destiny, all right — a destiny that will mean undue suffering for my child, and the children of so many in this warming and worried world. This pain is avoidable, or might have been, if we had seen leadership grow, instead of retract, on our now mounting environmental challenges.”

    http://www.huffingtonpost.com/betsy-rosenberg/reagan-environment-policy_b_1678153.html

  13. Craig D says:

    To elaborate, methane is 100 times more potent of a GWG than carbon dioxide. So, the methane seeps are important. Interestingly, the fracking in Pennsylvania is resulting in methane bubbling up in some of the rivers there. As fracking goes global, don’t you think that much of the methane released from the rock will escape directly to the atmosphere? If we add huge amounts of deeply buried methane to the amount about to be released from the clathrates and permafrost, we could be setting the stage for a warming not seen since the great anoxic event in the early Triassic.

  14. Mulga Mumblebrain says:

    A pivotal figure in the destruction of humanity. His attitude to life and all other to his grand self was summed up by his observation when he allowed great stands of 2,000 year old sequoia to be clear-felled-‘You seen one redwood, you seen ’em all’.

  15. Dennis Tomlinson says:

    Saint Ronnie turned a blind (pair of) eye(s) on the AIDS epidemic, lest he disrupt the benefits of ridding us from our queers and drug addicts.

  16. Rodel Urmatan says:

    100x not. I think it’s is more on the 20x range. But it’s still a potent GHG.

  17. Mauri Pelto says:

    It is time to be worried. Having worked on Greenland glaciers for thirty years, this is not the same Greenland ice Sheet, the climate has changed enough to alter the very fabric of the ice sheet, from its velocity, to its surface color, to its melt rate. Glacier by glacier it is unusual to find one that is not being impacted.

  18. Will Fox says:

    Methane is 25 times as potent a heat-trapping gas as CO2 over a 100 year time horizon, but 72 to 100 times as potent over 20 years:

    http://thinkprogress.org/climate/2011/12/01/379675/nature-climate-experts-thawing-permafrost-warming-of-deforestation/

  19. Tom L says:

    He also dumped the nation’s mentally ill onto the streets creating an instant homelessness crisis. That’s freedom!

  20. Dennis Tomlinson says:

    And busted PATCO, Star Wars, Iran Contra, tripled the national debt… I keep telling my Right Wing friends to read “Tear Down this Myth”, but they will not heed my pleas – opting instead to contribute to online funds dedicated to creating a Rushmore Ronnie.

  21. K Krieger says:

    Joe Romm talks of Lara Koenig’s “Scientific Reticence”; here is what Hansen said “I suggest that `scientific reticence’, in some cases, hinders communication with the public about dangers of global warming. If I am right, it is important that policy-makers recognize the potential influence of this phenomenon.” http://iopscience.iop.org/1748-9326/2/2/024002/fulltext/
    Sure enough, here is what the New York Times reporter Kelly Slivka reported about the Greenland meltdown: “While scientists described it as an “extreme event” not previously recorded from space, they hastened to add that it was normal in a broader historical context.” http://www.nytimes.com/2012/07/25/science/earth/rare-burst-of-melting-seen-in-greenland-ice-sheet.html?_r=1
    Normal? What’s the matter with these scientists? Surely they too can for the mainstream media put the Greenland meltdown into a context like Joe Romm did. One wonders what institutional pressures these scientists are under to be scientifically reticent?

  22. Yes, the ice is a couple of miles thick, at least at the center. The concern is that this surface melting could be the start of a partial or complete melting of the entire ice mass. That would cause sea level rises of 10 to 20 feet (or more) inundating the world’s coastal areas where most people live and many, if not most of our cities are built.

  23. Tom L says:

    Who’s next? Custer?

  24. Paul Magnus says:

    That’s what u get for electing a movie star to president.
    Not sure who’s to blame here….

  25. Paul Magnus says:

    Even if it were something that had happened before why don’t they just let the media find that out on their own?

  26. Michael Pope says:

    Even if the total thawing of the GIS surface area has occurred before (it has) it seems likely that we have already passed a tipping point where Greenland is concerned. That point was achieved when the CO2 emitted into the atmosphere was sufficient to result in loss of the ice sheet, even if we immediately stopped all greenhouse gas emissions.

    The fact is that emissions to-date have resulted in ~0.8C increase in average surface temperature. Even if further emissions ceased immediately – and there is no possibility of this happening – sufficient CO2 has already been emitted to double the present increase in average temperature, ie: to +1.6C.

    It needs to be remembered that Arctic amplification is already in the order of x2 – x3 times average global temperature. In other words, we have already emitted sufficient CO2 to assure a rise in Arctic temperature in the order of 3C-6C, sufficient to ensure continued and accelerated melting of the GIS and permafrost.

    As Dr Shakhova and others have pointed out this will increase the risk of a major methane excursion from the East Siberian Arctic Shelf. Were this to result in relatively sudden release of >50Gt methane, the result would be the passing of yet another tipping point – sudden and irreversible change, not to the GIS, but to the global climate.

  27. Terry Moran says:

    A peek at this graph from gisp2, shows we’ve only seen one event like this since the Viking Age.and only 6 in last 2000 yrs.
    This was a very unusual occurrence.
    http://www.gisp2.sr.unh.edu/DATA/alley1.html

    Terry

  28. BillD says:

    The PBS Newshour covered the story last night and the NASA scientist was so cheerful and matter of fact that it was difficult to get the idea that the melting of the Greenland ice sheet was anything to be concerned about. Toward the end, he was asked to put this in perspective and smiled saying that “oh yes, the warming of the arctic, lose of sea ice etc. are really extreme. But one had to be really inturn to realize that these are serious issues. Yes, scientific reticence.

  29. Scott says:

    And yet they don’t provide us with actual high definition photos in real color?