News24

Satellites - new Greenland ice melt

2012-07-24 22:33

Washington - Greenland's surface ice cover melted this month over a larger area than ever detected in more than 30 years of satellite observations, Nasa said on Tuesday.

According to measurements from three separate satellites analysed by Nasa and university scientists, an estimated 97% of the ice sheet surface thawed at some point in mid July, the agency said in a statement.

"This was so extraordinary that at first I questioned the result: was this real or was it due to data error?," said Nasa's Son Nghiem.

The expert recalled noticing that most of Greenland appeared to have undergone surface melting on 12 July while analysing data from the Indian Space Research Organisation's Oceansat-2 satellite.

Results from other satellites confirmed the findings. Melt maps drawn up showed that on 8 July about 40% of the ice sheet's surface had melted, rising to 97% four days later.

The news comes just days after Nasa satellite imagery showed that a massive iceberg twice the size of Manhattan had broken off a glacier in Greenland.

"This event, combined with other natural but uncommon phenomena, such as the large calving event last week on Petermann Glacier, are part of a complex story," said Tom Wagner, Nasa's cryosphere programme manager.

In the summer, on average about half of the surface of Greenland's ice sheet melts naturally, Nasa said. Normally, most of that melt water quickly refreezes at high elevations, while in coastal regions some of it is retained by the ice sheet while the rest flows into the ocean.

"But this year the extent of the ice melting at or near the surface jumped dramatically," Nasa added.

Researchers have yet to determine whether the melt, which coincided with an unusually strong ridge of warm air over Greenland, will contribute to a rise in sea level.

Nasa said that even the area near the highest point of the ice sheet, located 3.2km above sea level, showed signs of melting.

According to glaciologist Lora Koenig, who was part of the team analysing the data, melting incidents of this type occur every 150 years on average.

"With the last one happening in 1889, this event is right on time," Koenig said. "But if we continue to observe melting events like this in upcoming years, it will be worrisome."

Comments
  • Amanda - 2012-07-25 07:10

    "With the last one happening in 1889, this event is right on time," Koenig said. "But if we continue to observe melting events like this in upcoming years, it will be worrisome." Oh, it seems it's just a natural cycle then. Stop with these stupid global warming scare stories.

      robin.stobbs.9 - 2012-07-25 09:13

      Bravo Amanda!

      komorison - 2012-07-25 10:37

      Amen! Global warming hoax!

      klippies.coke.7 - 2012-07-25 11:30

      Spot on Amanda

  • dewalds3 - 2012-07-25 08:04

    Oom Siener : 'Wanneer die ys begin smelt...'

  • iceman196 - 2012-07-25 08:19

    in the meantime, polar bears have to wait even longer for there hunting season to start as it takes longer for the oceans to solidify in winter, you think global warming is a myth, you think its a scare story, I wish it was, just wait, carry on with polluting the atmosphere, you people just dont get it, 'cant happen to me' attitude

      daan.vandenberg.773 - 2012-07-25 08:44

      Beautifull Sea View Stands for Sale in Witbank. Buy NOW!

      robin.stobbs.9 - 2012-07-25 09:21

      Yes, Ian. Global warming (sic!) IS a myth - changing climates is not. Climates have changed since the Earth had climates to change and will carry on doing so for ever and a day. Polar bears do not have to wait longer for THEIR hunting season - they hunt in THEIR summer and hibernate during winter. Polar bear populations are INCREASING throughout their range. Please do some research and read some scientific literature. "Reality Check: 'Alaska is having one of their coldest summers on record, you silly New York Times reporter person. If you put asphalt on permafrost, it will melt. In 1954, Canada had to relocate their largest Arctic community due to melting permafrost. Pretending that melting permafrost is something new is typical of the crap reporting we have come to expect from the New York Times. Cornelia Dean appears to be a propagandist rather than an actual reporter". Perhaps you are not aware of the fact that the North-West Passage was clear of ice in the early 1930s but it has not been clear of ice since then - so much for 'global warming'!

      robin.stobbs.9 - 2012-07-25 09:21

      Weather Channel Founder John Coleman: 'There is no significant man-made global warming. Carbon Dioxide is not a pollutant' . Read: http://wattsupwiththat.com/2012/07/23/john-coleman-on-the-california-cap-and-trade-law/

      crazyjourno - 2012-07-25 10:52

      @Daan! That is very funny! Whahahahahahahaaa lol

      ernst.j.joubert - 2012-07-25 11:25

      @Robin: Your source of information "wattsupwiththat" is laughable (as with your many other sources). The guys running this site have cyberbullied numerous climate scientists around the world. If they are right, why is it necessary to issue death threats against someones wife!? See below link: http://thinkprogress.org/climate/2012/01/15/404673/mit-climate-scientist-wifecyberbullying-pushed-by-deniers/

      robin.stobbs.9 - 2012-07-25 11:34

      @Ernst - your reference is such a reliable source. I'm amazed at your knowledge ;-)

      ernst.j.joubert - 2012-07-25 11:45

      @Robin: Robin may I make a suggestion to you: Contact the top scientists in the world that are working in climate science and ask them what their opinions are on the issue.

  • robin.stobbs.9 - 2012-07-25 09:23

    Any moment now Ernst will be coming on with his endless crap about 98% of scientists etc ..... Well read this: Since 1998, more than 31,000 American scientists from diverse climate-related disciplines, including more than 9,000 with Ph.D.s, have signed a public petition announcing their belief that “…there is no convincing scientific evidence that human release of carbon dioxide, methane, or other greenhouse gases is causing or will, in the foreseeable future, cause catastrophic heating of the Earth’s atmosphere and disruption of the Earth’s climate.” Included are atmospheric physicists, botanists, geologists, oceanographers, and meteorologists. So where did that famous “consensus” claim that “98% of all scientists believe in global warming” come from? It originated from an endlessly reported 2009 American Geophysical Union (AGU) survey consisting of an intentionally brief two-minute, two question online survey sent to 10,257 earth scientists by two researchers at the University of Illinois. Of the about 3.000 who responded, 82% answered “yes” to the second question, which like the first, most people I know would also have agreed with. Then of those, only a small subset, just 77 who had been successful in getting more than half of their papers recently accepted by peer-reviewed climate science journals, were considered in their survey statistic. That “98% all scientists” referred to a laughably puny number of 75 of those 77 who answered “yes”.

      robin.stobbs.9 - 2012-07-25 09:23

      That anything-but-scientific survey asked two questions. The first: “When compared with pre-1800s levels, do you think that mean global temperatures have generally risen, fallen, or remained relatively constant?” Few would be expected to dispute this…the planet began thawing out of the “Little Ice Age” in the middle 19th century, predating the Industrial Revolution. (That was the coldest period since the last real Ice Age ended roughly 10,000 years ago.) The second question asked: “Do you think human activity is a significant contributing factor in changing mean global temperatures?” So what constitutes “significant”? Does “changing” include both cooling and warming… and for both “better” and “worse”? And which contributions…does this include land use changes, such as agriculture and deforestation?

      ernst.j.joubert - 2012-07-25 11:37

      @Robin.stobbs: You know Robin consulting sources (like wattsupwiththat) that cyberbully climate scientists and worse still are not even peer reviewed, only exposes your ignorance. Perhaps you should read the link below: http://www.skepticalscience.com/global-warming-scientific-consensus-intermediate.htm

      robin.stobbs.9 - 2012-07-25 14:05

      @Ernst - Cool, is the name of the game. First: You have no idea who I am nor who I know and who my associates / colleagues are. Second; don't glibly base your perceptions of what I write here by the odd 'easy' reference I quote - they are there for people like yourself who cannot (?? will not ??) understand the 'heavy stuff'. OK?

      daniel.nel.142 - 2012-07-28 11:11

      Impressive stats @Robin, however global warming is a misnomer, I believe climate change is more appropriate. The year with no summer was 1816 which brought about by the 1815 eruption of Mount Tambora in Indonesia. The earth is living organism and it changes in powerful ways, something scientists still cannot measure since there too many variables . Our current lifestyle is simply not sustainable and will have to change as the climate changes.

      ernst.j.joubert - 2012-07-28 11:38

      @Robin: 98% of the scientists working in climate scientists agree that there is substantial evidence that human activity is damaging the stability of the climate. A 2010 paper in the Proceedings of the National Academy of Sciences of the United States (PNAS) reviewed publication and citation data for 1,372 climate researchers and drew the following two conclusions: (i) 97–98% of the climate researchers most actively publishing in the field support the tenets of ACC (Anthropogenic Climate Change) outlined by the Intergovernmental Panel on Climate Change, and (ii) the relative climate expertise and scientific prominence of the researchers unconvinced of ACC are substantially below that of the convinced researchers.

  • delish7564 - 2012-07-25 10:40

    Well Greenland is so-called for a reason, namely it used to be green, so perhaps it is reverting, slowly, to its original state!

  • lasherza - 2012-07-25 12:51

    This im afraid is the natural order of things.. As we ( human race ) expands in unprecedented numbers which is an inevitability we must accept the fact that earth cannot be our only refuge in the next 200 years. It will become impossible to live and sustain life here. NASA must resume the space program we must seek other worlds. The Sci-fi community in there wisdom have been prophesying this for decades. It will happen ..exciting times ahead for the human race interspersed with the usual tragedy and catastrophe. . .

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