More hype on Greenland's summer melt

Satellite image of dark blue melt ponds
Satellite image of dark blue melt ponds (Photo credit: Wikipedia)

You may recall the bogus claim of “97% of Greenland Ice melted”, that was dialed back (REP’s last story on WUWT). Now there’s more of the same sort of stuff. See this PR, and note my bold for the money quote.

From the City College of New York

Greenland melting breaks record 4 weeks before season’s end

Melting over the Greenland ice sheet shattered the seasonal record on August 8 – a full four weeks before the close of the melting season, reports Marco Tedesco, assistant professor of Earth and atmospheric sciences at The City College of New York.

The melting season in Greenland usually lasts from June – when the first puddles of meltwater appear – to early-September, when temperatures cool. This year, cumulative melting in the first week in August had already exceeded the record of 2010, taken over a full season, according to Professor Tedesco’s ongoing analysis.

“With more yet to come in August, this year’s overall melting will fall way above the old records. That’s a goliath year – the greatest melt since satellite recording began in 1979,” said Professor Tedesco.

This spells a change for the face of southern Greenland, he added, with the ice sheet thinning at its edges and lakes on top of glaciers proliferating.

Professor Tedesco noted that these changes jibe with what most of the models predict – the difference is how quickly this seems to be happening.

To quantify the changes, he calculated the duration and extent of melting throughout the season across the whole ice sheet, using data collected by microwave satellite sensors.*

This ‘cumulative melting index’ can be seen as a measure of the ‘strength’ of the melting season: the higher the index, the more melting has occurred. (The index is defined as the number of days when melting occurs multiplied by the total area subject to melting.)

Dr. Thomas Mote, Professor of Geography at the University of Georgia and colleague of Professor Tedesco, confirmed that the cumulative melt in 2012 had surpassed that of 2010 using a similar analysis.

The August 8th record differs from NASA’s announcement of unprecedented melting in mid-July, reported by Professor Tedesco and other researchers. Then, they found that the Greenland ice sheet had melted over 97 percent of its surface.

“That event was exceptional in the sense that it was an extremely rare event,” said Professor Tedesco. “Imagine Rio de Janeiro under a layer of snow and you get the idea.”

The extreme melting detected in mid-July, on the other hand, generated liquid water that refroze after a few days. “This changed the physical properties of the snowpack – making a slushy layer that turned into an icy crust after refreezing – but very likely it did not add to the runoff of meltwater that makes sea levels rise.”

The cumulative melting index, on the other hand, does account for water flowing to the ocean. The same meltwater can affect ice dynamics by lubricating the base of the ice sheet and speeding its slide toward the sea.

This year, Greenland experienced extreme melting in nearly every region – the west, northwest and northeast of the continent – but especially at high elevations. In most years, the ice and snow at high elevations in southern Greenland melt for a few days at most. This year it has already gone on for two months.

“We have to be careful because we are only talking about a couple of years and the history of Greenland happened over millennia,” cautioned Professor Tedesco. “But as far as we know now, the warming that we see in the Artic is responsible for triggering processes that enhance melting and for the feedback mechanisms that keep it going. Looking over the past few years, the exception has become part of the norm.”

###

* The National Snow and Ice Data Center provided satellite data from the United States Air Force Defense Meteorological Satellite Program.

The NASA Cryospheric Sciences Program and the National Science Foundation (NSF) sponsored this research.

Note: An upcoming paper submitted by Professor Tedesco and his colleagues examines the losses and gains that the Greenland ice sheet could experience, as projected through the end of the 21st Century according to different CO2-level scenarios.

Online:

Greenland Melting www.greenlandmelting.com

Profile http://www1.ccny.cuny.edu/prospective/gsoe/ese/directory/profile-record.cfm?customel_datapageid_1237265=1252241

Video: Bridge destruction over Watson River, Greenland, likely a consequence of cumulative melting. (Filmed by M.Tedesco) http://www.youtube.com/watch?v=kKjXKAatiIs

NASA Release: Satellites See Unprecedented Greenland Ice Sheet Surface Melt http://www.nasa.gov/topics/earth/features/greenland-melt.html

===========================================================

This quote…

“That event was exceptional in the sense that it was an extremely rare event,” said Professor Tedesco. “Imagine Rio de Janeiro under a layer of snow and you get the idea.”

In juxtaposition with this one:

“That’s a goliath year – the greatest melt since satellite recording began in 1979.”

…has to be one of the most ridiculous ones I’ve ever seen.

How rare? Well professor, show me the records of such melts prior to satellite monitoring and you might have an argument.  Greenland melts every summer. How many summer in the past 1000 years have such levels of melt? I don’t think he can tell us. Is a 1 in 30 year event “rare”?

As for the reason, I think this figures in:

I refer you to this photograph of a Moulin in Greenland:

http://wattsupwiththat.com/2010/11/03/greenland-ground-zero-for-global-soot-warming/

Image from National Geographic online slide show – Photo: James Balog – click for more

Balog writes:

In the winter a huge among of snow are accumulated on the Ice (2-3 meters, sometimes more) and we are not talking about 1 or 2 square-miles, it’s about 100.000′s of square miles (up to 1 million) on the Westside of the Ice cap and a similar picture on the Eastside… when the melting season starts in april-sep… the meltwater has to go somewhere, and for sure it goes downhill in huge meltwater rivers.

The black stuff on the bottom of the lakes is carbon dust and pollution in general… but not from one year, but several decades (the topographical conditions don’t change from year to year). On a flight over the Ice Cap a sky clear day, you can see hundreds of huge lakes with the black spot on the bottom.

See this experiment with soot on snow done by meteorologist Michael Smith of WeatherData where soot made a huge difference.

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August 15, 2012 2:29 pm

No wonder it’smelting with all of those microwave satellites pointing at it all day long…
REPLY: I know you meant to add /sarc but I have to point out (for those humorless anonymous haters out there like Rattus Norvegicus) that will point to it and and say “See? stoopid!” that it is passive microwave radiation emanating from the area observed, not an active scan like radar. Even if it were active scan, due to inverse square law we’d be talking milliwatts to microwatts per square meter. Hardly enough to make a difference. – Anthony

August 15, 2012 2:32 pm

And while I’m at it, couldn’t all those greenies up there not just clean all the muck out from the bottom of those pools? I mean, for the sake of the planet?
(/sarc unfortunately probably required for some…)

Tez
August 15, 2012 2:34 pm

There was far less ice there when the Vikings were farming Greenland for a period of 500 years beginning approx 1000AD.

AndyG55
August 15, 2012 2:38 pm

Haven’t the Iceland volcanoes been rather active of late?
How much of the ash from them makes it to Greenland, and how much does this affect melting?

David Larsen
August 15, 2012 2:39 pm

Alle schnee is gruene, nicht wiese.

Joachim Seifert
August 15, 2012 2:40 pm

In the 17 century, in the Little Ice Age, ice volume increased. globally.
… now we have higher temp levels and we MUST observe that this ice is
melting…
…..A complete normality with nothing alarming in it……. It is just a reversing
of the freezing process 300 years ago….. because we are on a global temp
level higher than in the 17 century…..
Alarming would be if global ice volume did not shrink…. We are back to normal
concerning the Arctic ice volume…. until it will grow again with the advance of the
next glacial time…..JS

Anders Ottosson
August 15, 2012 2:46 pm

The Vikings suffered alot when global warming reached Greeenland. And now the Scanidavians are next in the norse disaster-line. Sweden’s highest mountain has gained 200 cm since last year. It’s hot, hot, hot!
http://norran.se/2012/08/norrbotten/kebnekaise-ar-hogre-an-vanligt/

GuarionexSandoval
August 15, 2012 2:49 pm

“This year, Greenland experienced extreme melting in nearly every region – the west, northwest and northeast of the continent – but especially at high elevations. In most years, the ice and snow at high elevations in southern Greenland melt for a few days at most. This year it has already gone on for two months.”
I thought there was a graph that showed over the course of July this year there were maybe 5 days where, for a brief period of the day, the temperature exceeded 32F. That this happens over a period of two months doesn’t mean there is thawing for two months. Also, weren’t these thawing events supposed to be happening roughly every 150 years or so and the melt this year is, according to the author of that July melt paper, just about right on schedule?

highflight56433
August 15, 2012 2:51 pm

I guess the rest of us have NEVER noticed the snow melting faster around the dog crap, bird doodoo or any other messy mass that is not as white as the pure driven snow.
Thank goodness Mike’s experiment will also be featured on Roger Pielke Senior’s blog. Nice! (extra SARC) Maybe there is some handsome grant money available to throw various dark objects onto some backyard snow. (Measure stick not included)

Steve R
August 15, 2012 2:59 pm

I hate to be so old school about this, but I see any evidence that we aren’t spiraling into another ice age as something to be optimistic about rather than something to dread.

Tad
August 15, 2012 3:04 pm

How do the Greenlanders feel about this extra melting? Is it a bad thing for them?

rogerknights
August 15, 2012 3:12 pm

The same meltwater can affect ice dynamics by lubricating the base of the ice sheet and speeding its slide toward the sea.

Hasn’t this been mostly debunked on earlier threads here? Fr instance, Greenland is a bowl, and this lubrication idea isn’t how it really works very much anyway.

highflight56433
August 15, 2012 3:20 pm

“The black stuff on the bottom of the lakes is carbon dust and pollution in general”
Has anyone actually sampled the material on the bottom of those lovely ponds? Not necessarily needed since the “stuff” is also found in any shovel of snow. I always thought snow was/is dirty. Probably always has been in areas where the prevailing weather (climate) lifts ground dust into the atmosphere. Maybe Antartica snow is cleaner than Greenland snow. Soon to be renamed Blackstuff Isle, or Carbondustlante. And why is the “stuff” “pollution in general?” Its hard to find any body of water that has a virgin bottom. And do those same ponds reemerge every year to accumulate an ever-growing amount of “stuff?”

Chris Edwards
August 15, 2012 3:34 pm

So how does this leave the ice covered Viking farmland ? that is a real world comparison, and who in their right mind would want the glaciers back to their full extent say in 1800?

August 15, 2012 3:35 pm

Rapid melting of the Greenland ice sheet was observed in the period 1935-1955 too, see:
http://www.agu.org/meetings/fm05/fm05-sessions/fm05_C41A.html last paragraph:
“To address this issue, we compiled a history of surface elevation changes of Jakobshavn Isbrae since the LIA. We first combined data from historical records, ground surveys, airborne laser altimetry, and field mapping of lateral moraines and trimlines. This record shows two periods of rapid thinning by about 70 meters, in the early 1950s and since 1997… [snip] …Nevertheless, aerial photographs collected in the 1940s and 50s indicate that thinning extended far inland.”
Further, the Greenland summer temperatures in the previous warm period were higher than in the recent past, see:
http://www.ferdinand-engelbeen.be/klimaat/greenland_temp.html
But I need to extend the trend over the most recent years.

David A. Evans
August 15, 2012 3:35 pm

Steve R says:
August 15, 2012 at 2:59 pm

I hate to be so old school about this, but I see any evidence that we aren’t spiraling into another ice age as something to be optimistic about rather than something to dread.

Agreed, but we just know they’re comparing to the microwave soundings from the MWP and early 20th century, so we have to be scared!
DaveE.

Per-Erik Aspling
August 15, 2012 3:40 pm

Nordenskiolds greenland expedition 1883
Melt river on the ice.
http://runeberg.org/polexp1883/0226.html
Water melt holes on the ice, some with black dust on bottom.
http://runeberg.org/polexp1883/0244.html
Map ower the in land ice expedition from Disco bay.
Altitude in meters.
Left map part.
http://runeberg.org/polexp1883/0233.html
Middle part.
http://runeberg.org/polexp1883/0234.html
Right part.
http://runeberg.org/polexp1883/0235.html

Green Sand
August 15, 2012 3:40 pm

“The summer climate in the North Atlantic about the year 1000”
http://www.canadianmysteries.ca/sites/vinland/othermysteries/climate/4157en.html
“Roots of plants and deep Viking graves found in South Greenland in soil that is now tjaele (permafrost or permanently frozen ground) indicate that the annual mean temperature must have been 2-4°C warmer than now.”
Source: Knud Frydendahl, “The summer Climate in the North Atlantic about the Year 1000” in Viking Voyages to North America, Birthe L. Clausen (Denmark: Kannike Tryk A/S, 1993), 90-94.

Theo Goodwin
August 15, 2012 3:46 pm

rogerknights says:
August 15, 2012 at 3:12 pm
Yep! In Warmish nightmares, Greenland is a partially uncovered bowling ball and when the ice loses its grip – Kazaam!

wayne
August 15, 2012 3:46 pm

http://psc.apl.washington.edu/northpole/NPEO2012/WEBCAM1/ARCHIVE/npeo_cam1_20120815140422.jpg
http://psc.apl.washington.edu/northpole/NPEO2012/WEBCAM2/ARCHIVE/npeo_cam2_20120815124017.jpg
And the arctic melt ponds seem to be turning a whiter shade of pale. Isn’t this about four weeks earlier that the near past years?

davidmhoffer
August 15, 2012 3:48 pm

Even if it were active scan, due to inverse square law we’d be talking milliwatts to microwatts per square meter. Hardly enough to make a difference. – Anthony
>>>>>>>>>>>>>>>>>
Ah, but you’ve forgotten all those cell phones, millions upon millions of cell phones, each putting out a watt or so. Plus the cell towers themselves. Plus all those broadcast radio and television stations, plus the broadcast satellites we pick up on our satellite dishes. Carnage I say! Watts everywhere!
/SARC!
(I don’t usually add the /sarc to my comments as I rely on my wording to make it self evident, but in this case, I thought I’d better go with convention)

Ian W
August 15, 2012 3:52 pm

““We have to be careful because we are only talking about a couple of years and the history of Greenland happened over millennia,” cautioned Professor Tedesco. “But as far as we know now, the warming that we see in the Artic is responsible for triggering processes that enhance melting and for the feedback mechanisms that keep it going. Looking over the past few years, the exception has become part of the norm.”
So look at the Danish temperatures here — http://ocean.dmi.dk/arctic/meant80n.uk.php
What warming?
It would appear that the soot that Anthony points out is a far more likely reason for melt as the air temperatures are well within the normal range (you can go back looking at other dates too).
As the coastal ice in Greenland melted it disclosed farms so one can hardly say it is unprecedented melting. Is the good professor and friend in Georgia really that ignorant? Or are things carefully weasel worded to get published and retain funding?

James Abbott
August 15, 2012 4:01 pm

The melt figures for Greenland match the weather data. WeatherOnline shows that stations such as Nuuk and Scoresbysund have seen well above normal temperatures this summer with few days even recording maxima at average or below – almost every day of the summer has been above normal. Narsarsuaq has seen many clusters of days in the high teens and low twenties C – normal for July is about 14C. So its no wonder there has been a big melt this year.
NOAA report that for land temperatures
“Notably, it was the warmest July on record for the Northern Hemisphere, where the majority of Earth’s land mass is located. This is the fourth month in a row that the Northern Hemisphere has set a new monthly land temperature record.”
Its not hype – its happening.

P Wilson
August 15, 2012 4:07 pm

Its worth noting that Lora Koenig, a Nasa Goddard glaciologist and a member of the research team analyzing the satellite data, said that “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”.
http://www.bbc.co.uk/news/science-environment-19269571

Justthinkin
August 15, 2012 4:22 pm

Are they sure all that soot is not from the evil Vikings Suv’s,tractors,and steel plants that were operating there 700 years ago,when they were farming?
Surely there is a smart,young lawyer out there somwhere who wants to make a name for themslves by starting to sue these clowns for fraud?

kadaka (KD Knoebel)
August 15, 2012 4:23 pm

How do I apply for a research grant on carbon sequestering? I have a perfectly Green idea. Carbon powder in a spray can. Apply to walkways and driveways for solar powered snow and ice removal. Of course the can will be recyclable aluminum, that you can refill with the carbon (actually pulverized anthracite coal), with compressed air as the propellant, that you can supply from a bicycle pump. Since the carbon is not burned, and will end up in the ground and washed away by water, sequestering is achieved.
A wonderfully Green idea, with all of the expected efficiency and practicality.
Unfortunately the research and development to create a marketable product, the marketing, and the required political lobbying for the enforced mandated use of this important Earth-saving technology, will be quite expensive. I figure $10 million just for the development is quite reasonable, given current governmental rates. The efficacy has already been demonstrated by how fast black carbon (aka soot) is melting away Greenland and Arctic ice.
So, how do I get this Necessary Funding for Saving The Planet?

highflight56433
August 15, 2012 4:42 pm

In looking at a higher resolution photo, it appears all the darkening “stuff” is only on the ice downwind and to the east of the land forms; also very dark. And I do not see any of those bodies of water except to the west, another indication the “stuff” is local. If the culprit is carbon dust from manly activities (cigar smokin’ included), then the ice should be equally sooty and “pollution” covered. The edges are going to melt faster on the west with the easterly wind flow off the bare land.

AnonyMoose
August 15, 2012 4:55 pm

“How many summer in the past 1000 years have such levels of melt?”
I’d ask for 2000 or 3000 years, because 1000 includes the Little Ice Age, and we don’t know how unusual that was.

gregole
August 15, 2012 5:03 pm
Jim
August 15, 2012 5:06 pm

Tad, it’s funny you bring that up. I was watching a documentary online from Al Gore’s Current network that talked about Greenland and climate change. The people of Greenland, including the indigenous tribal persons, are absolutely thrilled about global warming and hoping that it continues. I guess for Al Gore that’s a bit of an inconvenient truth — you rarely hear anyone talk about the plusses of global warming. Of course, being an Al Gore production, it’s kind of slanted. For instance, the host takes a boat near a glacier and watches it calve into the sea as if glaciers never calved every summer before man existed.
Here’s the episode: http://current.com/shows/vanguard/89521833_i-heart-global-warming.htm

August 15, 2012 5:06 pm

Ref Anthony reply to Jimmy Haigh
August 15, 2012 at 2:29 pm
“…No wonder it’smelting with all of those microwave satellites pointing at it all day long…
‘… that will point to it and and say “See? stoopid!” that it is passive microwave radiation emanating from the area observed, not an active scan like radar….’
Gawd that brings back memories. I worked in EW for many years, (ship board). We had a Signalman who was deathly afraid of my antennas (all passive), and would stay well clear of them like they were contagious. Despite me explaining that they did not transmit he would have no part of it. One day I caught him studying an electronics course that he was taking in his off time and I figured that he would finally understand that my antennas were not going to kill him, After he finished the course he still avoided my antennas. I asked why. “Because they are sucking in all that RF.”
I gave up.
(Note, he was a highly proficient Signalman, it’s just that some core beliefs can’t be broken)

Jim
August 15, 2012 5:16 pm

Roger, you’re correct. The lubrication theory is false. Greenland was glaciated 130 kya when global temps were 5C warmer than present, so it’s safe to say it isn’t going anywhere soon.
http://www.guardian.co.uk/environment/2008/apr/18/climatechange.scienceofclimatechange?INTCMP=ILCNETTXT3487

David G
August 15, 2012 5:27 pm

Tez, the Vikings didn’t farm in Greenland for 500 years, not even close.

Tom in Worc.(usa)
August 15, 2012 6:13 pm

Shouldn’t the “researchers” be taking samples of the black shmutz at the bottom of the meltponds. Probably could determine its origins.

August 15, 2012 6:48 pm

It’s well worth reading about the 100 years of climate warming that was widely reported in the first half of the 20th century, including how all the glaciers and the Arctic were melting like never before.
http://kenskingdom.wordpress.com/2012/07/04/glaciers-icebergs-melt-as-world-gets-warmer/
http://www.waclimate.net/climate-history.html
These observations were undoubtedly not as precise as modern technology. However, they were probably close to the mark because the 19th century saw the end of the so-called little ice age.

tjfolkerts
August 15, 2012 6:55 pm

“You may recall the bogus claim of “97% of Greenland Ice melted”
Actually, no, I don’t recall any such claim anywhere by anyone at anytime. Could you provide a link to a reputable news source making such a claim?
I saw plenty of reports of 97% of the surface area experiencing some melting. I suppose that some casual readers might have misread the articles, but people misread science articles all the time even with the best of reporting.
So educate me — show evidence that the media made a bogus claim corresponding to “97% of Greenland Ice melted” as opposed to “97% of Greenland Ice SURFACE EXPERIENCED MELTING”, rather than WUWT making a bogus claim about bogus claims.

mbw
August 15, 2012 7:18 pm

“This quote…
“That event was exceptional in the sense that it was an extremely rare event,” said Professor Tedesco. “Imagine Rio de Janeiro under a layer of snow and you get the idea.”
In juxtaposition with this one:
“That’s a goliath year – the greatest melt since satellite recording began in 1979.”
…has to be one of the most ridiculous ones I’ve ever seen.”
I believe if you check you will find that Rio had a major snow storm in 1985. So, the comparison seems reasonable.

August 15, 2012 7:50 pm

“…The black stuff on the bottom of the lakes is carbon dust and pollution in general… but not from one year, but several decades (the topographical conditions don’t change from year to year). On a flight over the Ice Cap a sky clear day, you can see hundreds of huge lakes with the black spot on the bottom…”
Looks like what we’re seeing is the creation of the new Greenland coal deposits. As this carbon dust collects, and compresses under the expanding glaciers during the upcoming MIA (Modern Ice Age), these new deposits will ensure survival for future generations.
/sarc, of course…

Max
August 15, 2012 7:59 pm

Summit station Conditions:
-27 C -17 F
6.0 knots
95 degrees E
As of 08/16 00:58

Stephen Pruett
August 15, 2012 8:25 pm

TJFolkerts, The following is from the NASA press release, ” 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.” Because the term “surface” was never defined or even really described (it could mean all the ice on top of the ground), this press release seemed designed to give an impression of massive melting more than increased extent of normal melting of the topmost portion of the ice, amounting to a tiny fraction of the total ice. Of course the same press release included the term “unprecedented” in the title while explaining in the body of the article that this occurs every 150 years or so. It’s typical of the manner in which any unusual warming event is reported by both climate scientists and the media, while unusual cooling events are either ignored (mostly) or rationalized as an indirect effect of warming. Nothing bogus on this here, but high level bogosity index in the field and the media as a whole.

D. J. Hawkins
August 15, 2012 8:28 pm

David G says:
August 15, 2012 at 5:27 pm
Tez, the Vikings didn’t farm in Greenland for 500 years, not even close.

Looking at this from Wikipedia suggests an approximate 500 year occupancy:
http://en.wikipedia.org/wiki/History_of_Greenland
Take it for what ever you think it’s worth.

Graeme W
August 15, 2012 8:28 pm

tjfolkerts says:
August 15, 2012 at 6:55 pm
“You may recall the bogus claim of “97% of Greenland Ice melted”
Actually, no, I don’t recall any such claim anywhere by anyone at anytime. Could you provide a link to a reputable news source making such a claim?

It’ll depend on what you consider to be a reputable new source, of course, but try these links:
http://www.examiner.com/article/unprecedented-97-of-greenland-ice-sheet-melts-within-4-days
http://esciencenews.com/sources/the.guardian.science/2012/07/24/greenland.ice.sheet.melted.unprecedented.rate.during.july
http://www.illawarramercury.com.au/news/local/news/general/97-of-greenland-ice-sheet-melting/2635764.aspx
http://m.brisbanetimes.com.au/environment/climate-change/97-of-greenland-ice-sheet-melting-20120725-22pue.html
I’m sure you’ll point out that the articles also mention that it’s the surface that’s melting, but, taking the last one as an example, the headline says “97% of Greenland ice sheet melting”.
I ignored all the blog entries I found that talk about 97% of the ice sheet melting because they’re not a “reputable news source”, but they all took their lead from the news reports, and a lot of people didn’t appreciate the difference between the ice sheet melting and the ice sheet surface melting – it’s a subtle point that escaped a lot of people. Therefore, I think it’s legitimate to say that the MSM propogated the view that 97% of the ice sheet was melting because of their poor choice of words in headlines and leading paragraphs, or poor explanation of what really happened.

Graeme W
August 15, 2012 8:38 pm

Here’s another, higher profile link:
http://www.cbsnews.com/8301-205_162-57479558/97-percent-of-greenland-ice-experienced-melting-in-july/
To quote:

97 percent of Greenland ice experienced melting in July
(CBS News) Satellite imagery has revealed what NASA calls an “unprecedented” melting event over Greenland. The far northern Atlantic island, covered year-round in a thick sheet of ice, has experienced melting in over 97 percent of its ice sheet. Over a period of just four days, Greenland’s surface ice area melted over a larger area more than at any time in over 30 years of satellite observation.

Now, this can be (correctly) interpreted as 97% of the surface, but the sentence before that clearly states “melting in over 97 percent of its ice sheet”. The wording is such that many, many people will interpret that as CBS news reporting 97% of the ice sheet is melting, not the 97% of the surface of the ice sheet is melting.

Graeme W
August 15, 2012 8:41 pm

An example of a site that shows the interpretation that Anthony has commented on:
http://www.earthknowledge.net/index.php/knowledgeportal/93678-greenland-ice-sheet-melt-unprecedented
To quote:

NASA satellite measurements confirm that 97% of Greenland’s ice sheet has melted this summer, far more than ever before recorded.

dp
August 15, 2012 8:52 pm

I think the summer melt is a lot like my back yard. Some days my wife and I are there alone. Other days we may have a coyote visit. The day after, bunnies or deer. Raccoons show up every day. Once in a while a bear or cougar will appear. The precautionary principle says prepare so I carry a gun and a camera. So far I’ve only shot photos. Importantly I’m not over-prepared for one visitor or the other. The raccoons are probably the most dangerous visitors, and for them, tall boots should they decide we’re too close to the babies. Neither guns nor well-aimed imprecations do well against them, and they are known to carry rabies.
The precautionary principle applied to the arctic is simple – don’t over spend on one uncertainty vs another. You may choose badly and won’t have the political will or the funds to reverse course. Our planet has spent far more time colder than this and precious little time warmer. We’re in for a cold snap.

Bill Illis
August 15, 2012 8:53 pm

I would like to thank the scientists involved for gathering and so clearly presenting the data above.
(all NONE of it).
The ice-sheet temperature is -32.0C once you get past the first several metres. Melt water is going nowhere but refreezing in the ice-sheet (somewhere close to the surface).

wayne
August 15, 2012 9:06 pm

TJF, here’s the quote reported: (see former wuwt post, just search for 97%)
“A heat dome over the icy country melted a whopping 97 percent of Greenland’s ice sheet in mid-July, NASA said, calling it yet more evidence of the effect man is having on the planet.”
Kids blindly believe the media. Seems you would be outraged by this type of subliminal propaganda instead of defending, marginalizing and white-washing it Mr. Folkerts, for this type of hyperbole from your side is streaming it out daily. Didn’t I read somewhere in the past you were a teacher of young people?

kadaka (KD Knoebel)
August 15, 2012 9:23 pm

From tjfolkerts on August 15, 2012 at 6:55 pm:

“You may recall the bogus claim of “97% of Greenland Ice melted”
Actually, no, I don’t recall any such claim anywhere by anyone at anytime. Could you provide a link to a reputable news source making such a claim?

97 percent of Greenland ice experienced melting in July (bold added)


(CBS News) Satellite imagery has revealed what NASA calls an “unprecedented” melting event over Greenland. The far northern Atlantic island, covered year-round in a thick sheet of ice, has experienced melting in over 97 percent of its ice sheet. (…)

(…) But according to data compiled by three independent satellites and studied by researchers at NASA, 97 percent of the ice sheet thawed at some point in mid-July.

The incredible speed of the melt caught researchers off guard. Satellite maps taken on July 8 showed 40 percent of Greenland ice had melted. By July 12, that number had jumped to 97 percent.

Sure sounds like “97% melted” to me. Heck, ice ain’t hamburger. If someone hears “97% of the ice in the freezer thawed” they’ll take that to mean 97% of it melted, so that bit counts too.
Yes, with a careful reading of the online article, with info hidden in the online picture caption, you could figure out it is 97% of the ice sheet “at or near the surface”, that had thawed. But as a brief nightly TV news piece something like listened to during supper, cut up into little snippets for news blurbs, “97 of Greenland ice melted” will be the message conveyed.
Of course you did ask for a reputable news source, and this is CBS. YMMV.

kadaka (KD Knoebel)
August 15, 2012 9:30 pm

Whoops, Graeme W already got that one. “Reload, read, then post.” I should have that tattooed on the back of my hand so I can remember it better. 😉

AndyG55
August 15, 2012 10:12 pm

I’m pretty sure that the 97% melting.. without mentioning that it is surface melt, comes from the prime misrepresenter of climate spin in Australia.. Flannery !!

oMan
August 15, 2012 10:24 pm

Thanks. Two questions: (1) When the ice melts and refreezes, does the resulting surface have a higher reflectivity (reflectance? Shinier!) that might trick the satellites into thinking it is still melted? How much could that distort the readings? (2) It takes energy to melt ice. Presumably if we know the surface temperature, convection cooling effect, hours and intensity of sunlight, we can figure out how many (million) liters of melt-water could possibly result during the melt season. We know the area. So we will know the depth of the pools –probably a few millimeters or a centimeter (except where it gathers and creates moulins etc). H

Jon
August 15, 2012 10:26 pm

Could one factor for this be a couple of volcanos on Iceland not so long ago? Spraying the ice with black dust?

August 15, 2012 10:38 pm

@ James Abbott who says, “Its not hype – its happening.”
What’s happening James? It’s called weather. It’s summer in the northern hemisphere and this year it’s particularly hot in the US. Not unusual. I remember sweltering summers in So California in my childhood where for years the TV media went out and fried eggs on the sidewalk. (that was before the AGW hype) It was a curiosity, not a catastrophe.
This July was particularly COLD in many areas like Alaska, Britian, Africa, and New Zealand. Check out these articles with an open mind–not time to panic today:
“Record cold wave breaks 13 low temperature records: Juneau | Alaska news at adn.com”
http://www.adn.com/2012/07/14/2542733/record-cold-wave-breaks-13-low.html
“Most of the globe was cold, including snow in S. Africa and AUstralia-New Zealand.”
“Globally, for land/ocean surface combined, July 2012 averaged 0.47 degrees C. (0.85 F) above the 1951-1980 average, making last month the 13th warmest July on record. Records go back to 1880.” http://www.accuweather.com/en/weather-blogs/climatechange/how-did-july-2012-temperatures-1/69851
“The image below shows the satellite measured temperature anomalies of the lower troposphere for July 2012. The areas with the greatest warming relative to normal were over North America, Greenland and southeastern Europe. The far southern hemisphere experienced more widespread below-normal temperatures. ” http://www.accuweather.com/en/weather-blogs/climatechange/global-satellite-temperature-d/69263

Al Gore
August 15, 2012 10:41 pm

“NASA satellite measurements confirm that 97% of Greenland’s ice sheet has melted this summer, far more than ever before recorded.”
This is wrong. It’s not 97% it’s 997% and we are all doomed!!!

August 15, 2012 11:10 pm

The media-propagated claims about 97% of Greenland melting evaporate under scrutiny even faster than the claims about 97% of climate scientists “supporting” the warmist position.
http://wattsupwiththat.com/2012/07/18/what-else-did-the-97-of-scientists-say/
I’m also dubious about meltwater “lubricating the base of the ice sheet and speeding its slide toward the sea” to any significant degree.
From my recollection of high-school geography, there are submerged terminal moraines and depressions at the mouths of Norwegian fjords, because the weight of a sufficiently thick glacier or ice-cap squeezes out any water underneath it, even below sea level.
Meltwater flows over the surface of the ice cap (see photo above) and only descends underneath it through discrete channels (moulins). I do not see how the ice can “slide” on meltwater upon which it neither sits or floats.
Does anyone know of any peer-reviewed lit. quantifying this meltwater induced “sliding”?
Has anyone determined how much of the meltwater re-freezes after descending below the ice cap, where temperatures will be several degrees below freezing?

tty
August 15, 2012 11:23 pm

“Tez, the Vikings didn’t farm in Greenland for 500 years, not even close.”
Depends on what you call “close”. Greenland was first settled in 986 AD and the settlement there is last mentioned in icelandic sources in 1410 AD, but the archeological finds at Herjolfsnes indicates that the settlement probably survived at least to about 1450 AD. So – no – probably not quite 500 years.

George Lawson
August 16, 2012 12:43 am

and just in case anybody asks why the massive amount of meltwater has not had any effect on sea levels we might just drop this one in……
‘The extreme melting detected in mid-July, on the other hand, generated liquid water that refroze after a few days. “This changed the physical properties of the snowpack – making a slushy layer that turned into an icy crust after refreezing – but very likely it did not add to the runoff of meltwater that makes sea levels rise’

MonktonofOz
August 16, 2012 1:04 am

Fascinating that there are almost instant “peer reviews” of dubious statements. Who needs academics when there are the Graeme W and tty’s out there? Wonderful and should never be taken for granted for without the WUWT, JoNova et al the alternative view would never be “heard”.

Martin Lewitt
August 16, 2012 1:55 am

Hmmm, the models “jibe” with the climate, except for the “difference”:
“Professor Tedesco noted that these changes jibe with what most of the models predict – the difference is how quickly this seems to be happening.”
So the models still haven’t been fixed. Andreas Roesch published that ALL of the AR4 models had a positive surface albedo bias, i.e., under representing the surface albedo feedback by over 3W/m^2 globally and annually averaged. A figure about 4 times larger than the energy imbalance.
Scambos, who coauthored “Arctic Sea Ice Decline: Faster Than Forecast?” with Julienne Stroeve published in JGR, a few years ago noted that:
“Because of this disparity, the shrinking of summertime ice is about thirty years ahead of the climate model projections,”
Stoeve herself said: “The actual rate of sea ice loss in March, about ?1.8 percent per decade in the 1953 to 2006 period, was three times larger than the mean from the computer models,”
The problem is that the models just under represent the surface albedo feedback, it isn’t missing, so, in addition to the models are “matching” the recent warm climate incorrectly, the models will double down on their error by eventually catching up with the surface albedo, adding another 3+W/m^2 in the future to a climate that should have already had that absorbed energy in it. That is an amount comparable to the CO2 forcing that will also be added over the next century. I call it “Climate Models Gone Wild”. The model based “evidence” for net positive feedback to CO2 forcing was already shown to have no credibility back in 2006 by Roesch, and this was pointed out to the IPCC AR4 WG1 authors. Of course, they chose to report the model projections without any attempt to account for the impact of documented correlated model errors.

Bloke down the pub
August 16, 2012 2:50 am

Look on the bright side. If we do head into a new mini ice age we can just take off the expensive filter systems that were added to Western coal-fired power stations and pump soot into the atmosphere. Cheap geo-engineering solution to too much snow.

Kelvin Vaughan
August 16, 2012 3:13 am

David Ross says:
August 15, 2012 at 11:10 pm
Has anyone determined how much of the meltwater re-freezes after descending below the ice cap, where temperatures will be several degrees below freezing?
As 50% of Earths heat comes from within, it’s probably quite hot below the ice sheet.
The weight of ice probably means the bottom of the ice sheet is water anyway.
A Frenchmans head is convex but his beret dosn’t slip off when it gets wet in a downpour!

Entropic man
August 16, 2012 3:38 am

David Ross says:
August 15, 2012 at 11:10 pm
“the weight of a sufficiently thick glacier or ice-cap squeezes out any water underneath it, even below sea level.
Meltwater flows over the surface of the ice cap (see photo above) and only descends underneath it through discrete channels (moulins). I do not see how the ice can “slide” on meltwater upon which it neither sits or floats.”
I doubt you need peer review for this one. Direct experience may do it.I live in an area once under an ice sheets and its geography includes eskers, lines of deposited gravel till where watercourses once flowed below the ice.
Regarding lubrication, large volumes of water would tend to be squeezed out from between the ice and the underlying rock, if there was somewhere for it to flow. This is why you see meltwater flowing out under the terminal of a glacier. A thin layer if water would remain due to pressure melting, sufficient to provide lubrication. The same effect occurs when you ice skate; the pressure of your weight on the thin blades melts a thin film of water which reduces friction significantly.

Jimbo
August 16, 2012 3:41 am

The black stuff on the bottom of the lakes is carbon dust and pollution in general

Maybe it’s my pc monitor but it looks like I can also see black stuff at the sides of the ice too. But never mind soot and other pollutants it’s all down to the trace gas co2.
Anyway, more recent dumpings of snow at the summit.
http://stevengoddard.wordpress.com/2012/08/03/ice-gain-in-greenland-this-summer/

richardscourtney
August 16, 2012 3:48 am

George Lawson:
At August 16, 2012 at 12:43 am you say

and just in case anybody asks why the massive amount of meltwater has not had any effect on sea levels we might just drop this one in……
‘The extreme melting detected in mid-July, on the other hand, generated liquid water that refroze after a few days. “This changed the physical properties of the snowpack – making a slushy layer that turned into an icy crust after refreezing – but very likely it did not add to the runoff of meltwater that makes sea levels rise’

True, and the quote has another – perhaps more important – significance.
The melting and re-freezing of surface ice was observed on this occasion. So, it may have happened many times in the past when it could not have been observed.
Hence, you may want to “drop the quote in” whenever people claim the ice has “trapped” CO2 to provide an accurate indications of past atmospheric CO2 concentrations..
Richard

Alan the Brit
August 16, 2012 3:59 am

davidmhoffer says:
August 15, 2012 at 3:48 pm
As Numberwatch points out in Definitions, the mobile phone is a communications device that has failed to “kill its billions” of users! What better example of scare stories can you have?

Allan MacRae
August 16, 2012 4:22 am

This paper appears to be more global warming nonsense, another confirmation of The Law of Warmist BS. 🙂
http://wattsupwiththat.com/2012/02/28/the-gleick-tragedy/#more-57881
It should now be obvious that global warming alarmists and institutions like the IPCC have NO predictive track record – every one of their major scientific predictions has proven false, and their energy and economic recommendations have proven costly and counterproductive.
Some of us skeptics, in comparison, have an excellent predictive record. Here are some of our successful predictions from a decade ago, in 2002:
http://www.apegga.org/Members/Publications/peggs/WEB11_02/kyoto_pt.htm
1. Climate science does not support the theory of catastrophic human-made global warming – the alleged warming crisis does not exist.
3. Kyoto wastes enormous resources that are urgently needed to solve real environmental and social problems that exist today. For example, the money spent on Kyoto in one year would provide clean drinking water and sanitation for all the people of the developing world in perpetuity.
5. Kyoto will actually hurt the global environment – it will cause energy-intensive industries to move to exempted developing countries that do not control even the worst forms of pollution.
8. The ultimate agenda of pro-Kyoto advocates is to eliminate fossil fuels, but this would result in a catastrophic shortfall in global energy supply – the wasteful, inefficient energy solutions proposed by Kyoto advocates simply cannot replace fossil fuels.
The basis for the failed predictions of the IPCC et al is their insistence on a high climate sensitivity to CO2 – about an order of magnitude (10 times) too high.
This “climate sensitivity” is the essence of the mainstream argument between climate alarmists and climate skeptics, and it is now obvious that the alarmists are incorrect in their assumption of a “high sensitivity” value.
There has been no net global warming for 10-15 years.
Furthermore, the aerosol values used to force climate models to conform to observed cooling from ~1940-1975 were clearly fabricated to force this hindcasting to occur – actual aerosol measurements as reported by Douglas Hoyt and others disprove the fabricated aerosol values.
The rational conclusion is that the observed global cooling and warming trends are not unusual, are not primarily caused by humankind, and are in fact almost entirely natural in origin. That is the basis of our successful predictive track record, and that is, in all probability, the truth.
That is why we correctly stated, in 2002:
“Climate science does not support the theory of catastrophic human-made global warming – the alleged warming crisis does not exist.“
Furthermore, based on our above “natural origin” conclusion and observations of climate behaviour, in 2002 I (we) predicted imminent global cooling as the next probable step.
I still believe global cooling will occur, and can only hope that this cooling will be mild and not severe. My best guess, however, is a 40% probability that by 2020-2030 cooling will have commenced that is severe enough to significantly reduce the global grain harvest. Since I see no evidence that humanity is taking any mitigating measures to adapt to global cooling, I would very much like to be wrong in this last prediction.

Entropic man
August 16, 2012 4:27 am

tty says:
August 15, 2012 at 11:23 pm
“Tez, the Vikings didn’t farm in Greenland for 500 years, not even close.”
Depends on what you call “close”. Greenland was first settled in 986 AD and the settlement there is last mentioned in icelandic sources in 1410 AD, but the archeological finds at Herjolfsnes indicates that the settlement probably survived at least to about 1450 AD. So – no – probably not quite 500 years.
———————————————
You are on perilous ground here. One point of passionate argument on WUWT regards the existance, or non-existance of the Medieval Warm Period.

Entropic man
August 16, 2012 4:52 am

Those of us getting rather fed up with hype from all sides in the climate change debate may agree with Mr. Harrabin here.
http://www.bbc.co.uk/news/science-environment-19269571
NASA, CRU, NOAA, GWPF and WUWT please take note.

MonktonofOz
August 16, 2012 5:01 am

Allan MacRae; add one more to your list. If impoverished nations are “discouraged” from using coal to produce cheap electricity they are being condemned to eternal poverty. Only with cheap power can such countries start to enjoy the benefits the West take for granted.

richardscourtney
August 16, 2012 5:42 am

Entropic man:
I see you are still trolling. For example at August 16, 2012 at 3:38 am you say

A thin layer if water would remain due to pressure melting, sufficient to provide lubrication. The same effect occurs when you ice skate; the pressure of your weight on the thin blades melts a thin film of water which reduces friction significantly.

No. Pressure does not melt ice. That is a common ‘urban myth’ but it is false.
At all temperatures down to below -40 deg.C the surfaces of solid Ice surfaces are coated in a thin layer of liquid water which is only a few molecules thick. And this liquid film is why ice is slippery.
The reason for this film has only been determined by material science in recent decades, but the liquid surface of ice was discovered a long time ago by Michael Faraday (even you may have heard of him: he did some work on electricity).
All your arguments based on the ‘urban myth’ are wrong because the myth is wrong.
Richard

izen
August 16, 2012 5:45 am

While there may have been occasions in Greenland’s past when it was warmer than now, certainly during the Holocene maximum when solar input was around 7% higher, that did not coincide with the rest of the globe also being hotter. The MWP may have been warm in Greenland but is virtually undetectable in Himalayan ice-cores.
The present rate of melting in Greenland may not be unprecedented in the last 6000 years, but any past events were not associated with a global warming of the same magnitude.
On the issue of the 97% surface melt, it is a clear indication of the increasing incidence of extreme events. The preceding surface melt was around 150 years ago, but the one before that was 700 years ago and there have only been 6 events in the last 2000 years.
The incidence of Greenland surface melt was much higher during the Holocene maximum 7000 years ago when temperatures were higher, or at least higher than for the last few millennia. Present Greenland temperatures seem to be approaching those extremes with the concomitant increase in extreme melt event.
Without any contribution for increased solar input from orbital changes.
Here is a graph of the surface melt events in Greenland showing the way the incidence follows the temperature.
http://www.gisp2.sr.unh.edu/DATA/alley1.gif

Richard M
August 16, 2012 5:59 am

Since this year is not particularly warm globally, how can global warming be the cause. If it were you’d have expected even more melting in 2010, or 1998 or several other years. This is clearly another regional event just like the warm summer in the US. Since we’ve had many warm summers in the US in the past I suspect Greenland has had just as many.
Once again this demonstrates the dishonesty of the alarmists. They have to know what I stated above is true but they went ahead and spewed the propaganda anyways. As Dr. Hoerling stated in his rebuttal of NASA’s Hansen, all this does is reduce their credibility.

August 16, 2012 6:00 am

Tez says on August 15, 2012 at 2:34 pm :
“There was far less ice there when the Vikings were farming Greenland for a period of 500 years beginning approx 1000AD.”
============
Yes, nearly correct (let’s say possibly 250 years instead of 500) – and, as far as I can deduce, there was a lot less soot from the German and American factories landing on top of the pristine “Greenland Ice-sheet” back then. – So, how much warmer than today must the “Medieval Warm Period” have been? –
I see Wikipedia has ditched (or relegated to 2nd place) the Mann made “hockey-stick” in favor of a more devious (or half broken) one. One which acknowledges the “Medieval Warm Period” (MWP) but uses that period’s temperature peak as baseline, or T=0, resulting in making the year 2004 some 0.4, or even 0.5 deg. C warmer than at any earlier time during the past 2000 years.
Wikipedia also state: “The medieval warm period and little ice age are labeled at roughly the times when they are historically believed to occur, though it is still disputed whether these were truly global or only regional events.” –
Is Wiki really saying: ”historically believed to occur”? – Or should I change my optician?

August 16, 2012 6:03 am

richardscourtney says:
August 16, 2012 at 3:48 am
Hence, you may want to “drop the quote in” whenever people claim the ice has “trapped” CO2 to provide an accurate indications of past atmospheric CO2 concentrations..
Dear Richard,
Actually, remelt layers are readily observed in the coastal ice cores of Antarctica and in the Greenland ice core, that is why one could say that this happened 150 years ago at the Greenland summit too. For the CO2 levels, the only problem is that the air in the firn is sealed from exchanging with the atmosphere above, that makes that the air bubbles below the sealing have a smaller averaged years mixture than above the sealing and the ice age – gas age difference gets smaller too. But that doesn’t affect the accuracy of the CO2 levels themselves. Except that Greenland ice cores are unreliable for CO2 levels, due to inclusions of highly acidic volcanic dust from Icelandic eruptions, which interact in situ with sea salt carbonate dust inclusions.

August 16, 2012 6:08 am

Thanks for the feedback Kelvin Vaughan and Entropic man. Those were points I was not aware of. If the moderator allows, I’ll take this opportunity to open discussion about an aspect of the MWP that has been nagging me.
Why did Phil Jones mention the “Alerce series” in this Climategate email?
———————————–
From: Phil Jones
To: “Michael E. Mann”
Subject: Re: Fw: Law Dome O18
Date: Mon Feb 9 15:50:09 2004
[…]
At 10:19 09/02/2004 -0500, you wrote:
HI Phil,
Personally, I wouldn’t send him anything. I have no idea what he’s up to, but you can be sure it falls into the “no good” category.
[…]
At 02:46 PM 2/9/2004 +0000, Phil Jones wrote:
Mike,
FYI. Sent him the two series – the as received versions. Wonder what he’s up to? Why these two series? Used a lot more in the 1998 paper.
Didn’t want the Alerce series.
[…]
http://www.ecowho.com/foia.php?file=1076359809.txt&search=alerce
———————————–
The above email; the following two news reports from the 1990s (I read old newspapers) and the fact that Mann’s hockey stick only applies to the northern hemisphere; lead me to suspect that something is amiss. But I’m not sure. I’d like to hear any comments from more informed WUWTers.
———————————–
Tree Rings Show No Warming Tendency
New York Times July 13, 1993
http://www.nytimes.com/1993/07/13/science/tree-rings-show-no-warming-tendency.html
GROWTH rings from a 3,613-year-old South American tree show no evidence that human activity has had a warming effect on the climate, scientists say.
Two researchers report that annual rings in an alerce tree, the second oldest tree species known, show that although the climate near the west coast of South America has warmed and cooled many times over thousands of years, there has been no increase in temperatures during the industrial age.
The report appeared recently in the journal Science.
The scientists said their study did not contradict research suggesting that parts of the Northern Hemisphere have experienced warming trends. But the results do indicate that any so-called global warming is not really global, at least not yet.
Ricardo Villalba of the University of Colorado at Boulder and Antonio Lara of the University of Arizona said they measured the width of tree rings in 96 trunk wedges, or corings, taken from standing alerce trees or from stumps of harvested trees in Chile and Argentina. Average annual temperatures affect seasonal tree growth. As a result, it is possible to use the tree rings to reconstruct climatic conditions.
Mr. Villalba said that rings in the stump of one tree felled in 1975 showed that the tree had lived for at least 3,613 years. Other trees studied had lived from 325 to 2,248 years, he said.
Temperatures in the area, he said, were much higher before the industrial age than now. Summertime temperatures in southern South America increased from 1400 B.C. to 750 B.C. and then cooled, he said. The longest period when temperatures were above the mean for the area was from 80 B.C. to A.D. 160.
“The most recent warm periods were from A.D. 1720 to 1750, and from 1800 to 1880,” the study said. “The longest intervals with below-average temperatures were from 770 to 570 B.C., from A.D. 300 to 470, and from A.D. 1490 to 1700.”
“Global warming may not be a generalized problem,” Mr. Villalba said. “We need to know more about atmospheric circulation of temperatures” before science can draw any final conclusion about the effect of industry on global climate, he said.
———————————–
And of related interest.
———————————–
In Unexpected Places, Clues to Ancient and Future Climate Warming?
Tree Rings Say Not Yet
New York Times December 1, 1992
http://query.nytimes.com/gst/fullpage.html?res=9E0CEFDE1531F932A35751C1A964958260&pagewanted=all

Stubben
August 16, 2012 6:42 am

Per-Erik Aspling says:
August 15, 2012 at 3:40 pm

Nordenskiolds greenland expedition 1883
Melt river on the ice.
http://runeberg.org/polexp1883/0226.html
Water melt holes on the ice, some with black dust on bottom.
http://runeberg.org/polexp1883/0244.html

This is highly interesting. The black dust is named “krykonit” by Nordenskiöld. A search for “krykonit” in Bing gives among others a .pdf from 2002 by Frank T. Kyte “Tracers of the extraterrestrial component in sediments and inferences for Earth’s accretion history” http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20030062938_2003071760.pdf which cite the work of Nordenskiöld:

Murray and Renard (1 891) cited other work of their time describing possible “cosmic dust.” None appeared to be so conclusive in their results as the Challenger work, but they noted that Nordenskjold (1881, cited in Murray and Renard, 1891) collected dust in Greenland in deposits of “Krykonit.” These deposits, which occur in lakes on the Greenland ice sheet, are now known to contain some of the best-preserved concentrates of cosmic spherules yet discovered (Maurette et al., 1986).

The black dust in the melt ponds on the Greenland ice-sheet has cosmic origin.

beng
August 16, 2012 7:00 am

****
Theo Goodwin says:
August 15, 2012 at 3:46 pm
Yep! In Warmish nightmares, Greenland is a partially uncovered bowling ball and when the ice loses its grip – Kazaam!
****
When it melts, it’ll roll west into the Canadian archipelago & produce a seven-ten split.

August 16, 2012 7:26 am

Entropic,
Roger Harrabin is an eco-lunatic. He is the one pushing the human-cause runaway global warming hype, and you are a true believer in that ridiculous nonsense.

nc
August 16, 2012 8:01 am

Here is an interesting story of the rescue of a B-17 aircrew off the Greenland icecap by the use of a PBY amphibious aircraft on an icecap “lake” during WW-2. Note the lake disappeared after the rescue.
http://www.ultimatesacrifice.com/my_gal_sal_history.htm

Phil.
August 16, 2012 9:24 am

AnonyMoose says:
August 15, 2012 at 4:55 pm
“How many summer in the past 1000 years have such levels of melt?”
I’d ask for 2000 or 3000 years, because 1000 includes the Little Ice Age, and we don’t know how unusual that was.

Excluding this year, 4 times in the last 1000, 6 in the last 2000 and 12 in the last 3000. The peak was about 7000 years ago when it happened about every 25 years. The ‘once every 150 years’ refers to the average over the last 10000 years.

Phil.
August 16, 2012 9:32 am

oMan says:
August 15, 2012 at 10:24 pm
Thanks. Two questions: (1) When the ice melts and refreezes, does the resulting surface have a higher reflectivity (reflectance? Shinier!) that might trick the satellites into thinking it is still melted?

Actually it gets darker, that’s how they can determine that it’s melted.
http://www.meltfactor.org/blog/?p=514

Entropic man
August 16, 2012 9:49 am

Smokey says:
August 16, 2012 at 7:26 am
Entropic,
Roger Harrabin is an eco-lunatic. He is the one pushing the human-cause runaway global warming hype, and you are a true believer in that ridiculous nonsense.
—————————————-
I think that qualifies as an ad-hominem attack, Smokey, unless you can display convincing evidence. I note the emotional trigger words:- eco-lunatic,true believer, ridiculous nonsense. You are back to those political lobbyist tactics again.
He’s right about the headlines, though. A number of comments on WUWT reacted to the headline announcing the July 12th surface melting without reading the report properly. This very post is headed “More hype on Greenland’s summer melt”.
Other examples on WUWT include:-
“What planet does Michael Mann live on”
“James Hansen’s cherrypick”
“Climate change and the tooth fairy”
“Warming alarmism spreads faster, like a virus.”
To provide balance,here’s a chance for you to mine the alarmist websites for similar hyped catastrophic headlines.
.

Phil.
August 16, 2012 9:50 am

Tad says:
August 15, 2012 at 3:04 pm
How do the Greenlanders feel about this extra melting? Is it a bad thing for them?

They’re not too happy about this:
http://earthobservatory.nasa.gov/IOTD/view.php?id=78685

http://www.youtube.com/watch?v=kKjXKAatiIs&feature=player_embedded

Entropic man
August 16, 2012 10:01 am

Richad Courtney is right about the updated physics of low frictiom movement over ice surfaces. I was unable to lay hands on the original paper, but this gives a summary of what he found.
http://www.exploratorium.edu/hockey/skating1.html

richardscourtney
August 16, 2012 10:42 am

Ferdinand:
Thankyou for your response at August 16, 2012 at 6:03 am to my post at August 16, 2012 at 3:48 am.
It is always good to hear from you and – as we usually do – to ‘cross swords’.
Also, I noted your earlier post at August 15, 2012 at 3:35 pm which is also pertinent to my post. That earlier post of yours said

Rapid melting of the Greenland ice sheet was observed in the period 1935-1955 too, see:
http://www.agu.org/meetings/fm05/fm05-sessions/fm05_C41A.html last paragraph:

etc.
Your reply to my post says:

Actually, remelt layers are readily observed in the coastal ice cores of Antarctica and in the Greenland ice core, that is why one could say that this happened 150 years ago at the Greenland summit too. For the CO2 levels, the only problem is that the air in the firn is sealed from exchanging with the atmosphere above, that makes that the air bubbles below the sealing have a smaller averaged years mixture than above the sealing and the ice age – gas age difference gets smaller too. But that doesn’t affect the accuracy of the CO2 levels themselves. Except that Greenland ice cores are unreliable for CO2 levels, due to inclusions of highly acidic volcanic dust from Icelandic eruptions, which interact in situ with sea salt carbonate dust inclusions.

As I think you know, I agree your final point about the unreliability of Greenland ice cores due to volcanic contaminants.
But, as you also know, I strongly disagree with your assertion that “the air in the firn is sealed from exchanging with the atmosphere above”. The firn contains open porosity (i.e. it is not sealed) and variations in atmospheric pressure (i.e. weather) would pump air in and out of the firn.
However, those points are a distraction from the issue of the melts and re-melts.
The important point in direct relevance to my comment is stated by you when you say “remelt layers are readily observed in the coastal ice cores of Antarctica and in the Greenland ice core”. Indeed so. But that leads to two problems.
1. It cannot be known how many “remelts” happened but are not “readily observed”
and
2. The melting and refreezing must affect temporal resolution of the ice cores in unknown ways (i.e. annual layers are confused so cannot be resolved and must be ‘guessed’).
Richard

Gail Combs
August 16, 2012 11:09 am

Steve R says:
August 15, 2012 at 2:59 pm
I hate to be so old school about this, but I see any evidence that we aren’t spiraling into another ice age as something to be optimistic about rather than something to dread.
===========================
Agreed! I had frost bite as a kid and almost froze to death walking home from the school bus so I have a great respect for what really cold weather can do.

richardscourtney
August 16, 2012 1:02 pm

Friends:
At August 16, 2012 at 5:42 am I pointed out that the troll operating under the title Entropic man had based an untrue argument on an untrue ‘urban myth’. Subsequently, at August 16, 2012 at 10:01 am, he/she/they says:

Richad Courtney is right about the updated physics of low frictiom movement over ice surfaces. I was unable to lay hands on the original paper, but this gives a summary of what he found.
http://www.exploratorium.edu/hockey/skating1.html

“Updated physics”?!
As damage limitation that counts as being somewhat pathetic.

My rebuttal of his/her/their nonsense included this paragraph.

The reason for this film has only been determined by material science in recent decades, but the liquid surface of ice was discovered a long time ago by Michael Faraday (even you may have heard of him: he did some work on electricity).

Michael Faraday died on 25 August 1867. His work on the ice was completed more than 150 years ago.
Richard

richardscourtney
August 16, 2012 1:06 pm

As a PS, the troll was wrong that I had found his/her/their link. I did not know of it and I have posted on WUWT about the surface properties of ice in the past.
Richard

Entropic man
August 16, 2012 3:08 pm

Can’t win here. Perhaps I should post as “The Warmist Troll” from now on, just to keep Richard happy. Kind of him to tell me about Professor Somorjai’s work. It’s something I missed.
The ice moves, nevertheless
REPLY: I thought the idea of science was to determine truth, not to “win”. – Anthony

Joachim Seifert
Reply to  Entropic man
August 16, 2012 4:35 pm

You snuck into the climate science blog……please read JJ’s good
reply to your Warmist alarmism…… do repent, it is never
too late….

Entropic man
August 16, 2012 3:37 pm

REPLY: I thought the idea of science was to determine truth, not to “win”. – Anthony
I’m not talking about the science, though all it can usually give is probability, not truth.
“Truth” is more the province of politicians and priests.
I said “I cant win” because there’s no point in my indulging in further debate with Richard from now on. His perception of me as a paid warmist troll will probably lead him to automatically dismiss any evidence I present, regardless of its quality

Allan MacRae
August 16, 2012 4:59 pm

MonktonofOz says: August 16, 2012 at 5:01 am
Allan MacRae; add one more to your list. If impoverished nations are “discouraged” from using coal to produce cheap electricity they are being condemned to eternal poverty. Only with cheap power can such countries start to enjoy the benefits the West take for granted.
___________
Sorry Monkton, but increased cheap global energy supply is exactly what the radical enviros are trying to prevent. Please see the first three excerpts below.
Did you seriously think this was all about the phony global warming scare? That, apparently, is the smokescreen.
Skill-testing question for ALL:
WHAT IS THE REAL GREEN AGENDA?
Source:
http://www.green-agenda.com
___________
Excerpts:
“Complex technology of any sort is an assault on
human dignity. It would be little short of disastrous for us to
discover a source of clean, cheap, abundant energy,
because of what we might do with it.”
– Amory Lovins, Rocky Mountain Institute
“The prospect of cheap fusion energy is the
worst thing that could happen to the planet.”
– Jeremy Rifkin,
Greenhouse Crisis Foundation
“Giving society cheap, abundant energy would be the
equivalent of giving an idiot child a machine gun.”
– Prof Paul Ehrlich, Stanford University
“The only hope for the world is to make sure there is not another
United States. We can’t let other countries have the same
number of cars, the amount of industrialization, we have in the US.
We have to stop these Third World countries right where they are.”
-Michael Oppenheimer,
Environmental Defense Fund
“Global Sustainability requires the deliberate quest of poverty,
reduced resource consumption and set levels of mortality control.”
-Professor Maurice King
“We’ve got to ride this global warming issue.
Even if the theory of global warming is wrong,
we will be doing the right thing in terms of
economic and environmental policy.”
– Timothy Wirth,
President of the UN Foundation
“No matter if the science of global warming is all phony…
climate change provides the greatest opportunity to
bring about justice and equality in the world.”
– Christine Stewart,
former Canadian Minister of the Environment
“The data doesn’t matter. We’re not basing our recommendations
on the data. We’re basing them on the climate models.”
– Prof. Chris Folland,
Hadley Centre for Climate Prediction and Research
“The models are convenient fictions
that provide something very useful.”
– Dr David Frame,
climate modeler, Oxford University
“I believe it is appropriate to have an ‘over-representation’ of the facts
on how dangerous it is, as a predicate for opening up the audience.”
-Al Gore,
Climate Change activist
“It doesn’t matter what is true,
it only matters what people believe is true.”
– Paul Watson,
co-founder of Greenpeace
“The only way to get our society to truly change is to
frighten people with the possibility of a catastrophe.”
– emeritus professor Daniel Botkin
“The climate crisis is not a political issue, it is a moral and
spiritual challenge to all of humanity. It is also our greatest
opportunity to lift Global Consciousness to a higher level.”
-Al Gore,
Nobel Peace Prize acceptance speech
“We are on the verge of a global transformation.
All we need is the right major crisis…”
– David Rockefeller,
Club of Rome executive member
“We must make this an insecure and inhospitable place
for capitalists and their projects. We must reclaim the roads and
plowed land, halt dam construction, tear down existing dams,
free shackled rivers and return to wilderness
millions of acres of presently settled land.”
– David Foreman,
co-founder of Earth First!

August 16, 2012 5:20 pm

Entropic,
Let me be clear: Roger Harrabin is an eco-lunatic, a true believer, and he spouts ridiculous nonsense. Furthermore, the onus is not on scientific skeptics to provide “convincing evidence” of anything. That is the burden on those pushing the CAGW conjecture, and I have to tell you, they have failed. There is no convincing evidence for CAGW. But if you find any, be sure to post it here. Be prepared to defend your putative “evidence”.

richardscourtney
August 16, 2012 8:34 pm

Friends:
At August 16, 2012 at 3:08 pm and August 16, 2012 at 3:37 pm the troll who posts as ‘Entropic man’ complains that I am certain he is a paid troll. But he/she/they clearly hopes many don’t know the reason for my certainty. It is explained by posts on the thread at
http://wattsupwiththat.com/2012/08/14/why-we-need-debate-not-consensus-on-climate-change/
Below I copy two of my posts from that thread (which immediately followed one another in the thread) because they are especially informative and it saves people needing to find them.
Please note that Entropic man did not respond to these posts but must have seen them because he/she/they did make subsequent posts in that thread.
If Entropic man is withdrawing from WUWT it is probably because his/her/their paymaster has withdrawn funding following exposure of him/her/them. And one can assume he/her/they will be replaced.
Richard
——-
richardscourtney says:
August 16, 2012 at 6:00 am
Entropic man:
I see you are still trolling. Your post at August 16, 2012 at 3:58 am misquotes me as saying at August 16, 2012 at 1:04 am

I see no reason to think you are telling the truth on this thread when you claim you are not one of the many paid warmist trolls.

when I actually wrote

But, since you have refused to attempt justification of other falsehoods you posted on this thread, I see no reason to think you are telling the truth on this thread when you claim you are not one of the many paid warmist trolls.

Those falsehoods which you refuse to justify are your lies about the Stern Report. But you use your misquotation of me as an excuse to continue to refuse to justify those lies.
You are one of the worst slimey trolls it has ever been my misfortune to observe, and I am now convinced that you are paid to conduct your despicable trolling.
Richard
——–
richardscourtney says:
August 16, 2012 at 6:38 am
Friends:
I write to explain why I disbelieve the assertion of Entropic Man that he is not a paid troll.
At the listed time of August 16, 2012 at 1:04 am I wrote my post which Entropic Man answered. The local time here in the UK was 9:04 am: n.b. I made my post early this morning.
Subsequently, about 3 hours later At August 16, 2012 at 3:58 am Entropic Man made his reply. That would have been 11:58 am UK time: i.e. about noon. But in that post he says;

I go out to my archery club for an evening ( European time) and come back to abuse!

Clearly, he is claiming he resides in Europe and returned to find my post after having been out for the evening. But my post was in the morning and he replied to it before the evening (wherever he abides in Europe).
Obviously, Entropic man is a fake. He claims to be in Europe but he is not. He claims to have made a post in the evening but he did not. And he claims to not be a paid troll and I don’t believe it.
Richard

David Jones
August 17, 2012 1:06 am

O H Dahlsveen says:
August 16, 2012 at 6:00 am
Tez says on August 15, 2012 at 2:34 pm :
“There was far less ice there when the Vikings were farming Greenland for a period of 500 years beginning approx 1000AD.”
============
Yes, nearly correct (let’s say possibly 250 years instead of 500) –
Let’s say: http://www.co2science.org/articles/V7/N22/EDIT.php

David Jones
August 17, 2012 1:12 am

Entropic man says:
August 16, 2012 at 4:27 am
tty says:
August 15, 2012 at 11:23 pm
“Tez, the Vikings didn’t farm in Greenland for 500 years, not even close.”
You are on perilous ground here. One point of passionate argument on WUWT regards the existance, or non-existance of the Medieval Warm Period.”
I think these summarise the existence and world-wide extent of the MWP
http://pages.science-skeptical.de/MWP/MedievalWarmPeriod1024x768.html
http://wattsupwiththat.com/2012/03/22/more-evidence-the-medieval-warm-period-was-global/

Entropic man
August 17, 2012 2:50 am

I’ve no problem with the Medieval Warm Period. Recent tree ring confirmation of Roman period warmth equal to 20th century levels rather reinforces my own view that we are living in a period of long term cooling as changes in the Earth’s orbital eccentricity move us towards towards the next glacial period, accelerated in the LIA due to a temporary reduction in solar output, and reversed by cAGW from 1900 on.
http://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate1589.html

izen
August 17, 2012 3:07 am

While Dick Courtney and Entropic man argue the arcana of …. something or another, the thread topic of whether the reporting of the melt in Greenland is ‘hype’ or not seems to be getting lost.
The rate of melting in Greenland has already accelerated over the last decade, this even greater rate of melting this year comes on top of this. Claiming that pointing this put is ‘hype’ seems to be based on a desire to minimise the observed acceleration and reject the implications of even greater rates of melt this year.
Here’s the already increased base from which this years melt is an increase –
Eric Rignot1,*, Pannir Kanagaratnam2,*
Using satellite radar interferometry observations of Greenland, we detected widespread glacier acceleration below 66° north between 1996 and 2000, which rapidly expanded to 70° north in 2005. Accelerated ice discharge in the west and particularly in the east doubled the ice sheet mass deficit in the last decade from 90 to 220 cubic kilometers per year. As more glaciers accelerate farther north, the contribution of Greenland to sea-level rise will continue to increase.
So the record melt a month from the end of the melting season is on top of a doubling of the melt rate over the last decade.
All of this exceeds any computer modelling of possible ice-cap melting which is clearly underestimating the rate of ice mass loss and therefore the rate of sea level rise.

Entropic man
August 17, 2012 3:38 am

Smokey says:
August 16, 2012 at 5:20 pm
Let me be clear: Roger Harrabin is an eco-lunatic, a true believer, and he spouts ridiculous nonsense. Furthermore, the onus is not on scientific skeptics to provide “convincing evidence” of anything.
—————————–
We are not discussing cAGW at this point, we are discussing Roger Harrabin and I. We disagree with you on cAGW. This does not make us insane. Nor does it mean that we are of that opinion based on faith, rather than on our assessment of the evidence. Nor does you sceptical stance on cAGW make you insane or credulous.
To imply either is insulting and diminishes a debate which should be about the science, not the sanity of the debaters.

Sasha
August 17, 2012 4:50 am

The graphic gives a totally misleading impression that Greenland is becoming ice-free – even where the ice is still 3km thick.

August 17, 2012 5:31 am

Entropic says:
“We are not discussing cAGW at this point, we are discussing Roger Harrabin and I. ”
We are discussing wild-eyed “hype”. Read the headline.
Since there is exactly zero scientific evidence for catastrophic AGW, to keep harping on it as if it actually exists is at least borderline insane. The rest of us are skeptical of CAGW because that is the default position when there is no supporting evidence. Occam’s Razor says that the simplest explanation – natural variability within long term parameters – is the correct explanation.

richardscourtney
August 17, 2012 5:56 am

izen:
re. your post at August 17, 2012 at 3:07 am.
Please see the above exchange between Ferdinand Engelbeen and myself.
There is nothing unusual in the recent melting of the Greenland Ice Sheet.
Melting and refreezing is a common event.
Also, in addition to your false claim that recent melting of the Ice Sheet is unusual, your post makes personal remarks. Until the paid troll made deliberately misleading remarks all my posts in this thread were directly pertinent to the subject of the thread. I then posted to object to the nature of those remarks and I made one – only one – post to inform about the troll.
And you have been told not to abuse me with diminutives.
Richard

Bill Illis
August 17, 2012 6:30 am

The Greenland ice-sheet temperature is -32C immediately below the surface. It stays that temperature for about 1500 metres down and then it slowly warms up until bedrock is reached where it is -2.7C and it melts given the higher pressure.
http://ars.sciencedirect.com/content/image/1-s2.0-S0277379104002689-gr3.jpg
http://www.eos.ubc.ca/research/glaciology/research/Publications/LhommeClarkeMarshall(QSR-2005).pdf
The snow that fell on Greenland during the Holocene is 600 metres down and the snow that fell during the last glacial maximum is 1300 metres below the surface. It accumulates every year despite a few days each two years that get above 0.0C.
The ice at the bottom of the ice-sheet is only 120,000 to 130,000 years old and the temperature at the bottom of the ice-sheet is -2.7C which is enough to melt the 125,000 year old ice when it gets there. It slowly trickles as water now to low points on the Greenland bedrock (potentially making it to the ocean in a few places – potentially staying as rock-hard-wet-water-ice in other places). One new drill-site, NEEM, at a northern summit might have the only non-melted ice at the bottom.
So, Greenland does not melt from the top, it melts from the BOTTOM [and from the SIDES which are continually replenished from ice flow from the summit high points].
That is the science. Not this +1.0C 4 melt day garbage being foisted onto the warmers minds of late.

Entropic man
August 17, 2012 9:18 am

izen says:
August 17, 2012 at 3:07 am
Bill Illis says:
August 17, 2012 at 6:30 am
If one of you can give me volumes relased from the Greenland ice cap by the recent event, annually or decadally for recent years I can estimate the effect on sea levels.

August 17, 2012 11:03 am

izen says:
August 17, 2012 at 3:07 am
The rate of melting in Greenland has already accelerated over the last decade, this even greater rate of melting this year comes on top of this. Claiming that pointing this put is ‘hype’ seems to be based on a desire to minimise the observed acceleration and reject the implications of even greater rates of melt this year.
The problem is that there were no satellites before the ’70s of the past century. But the melt in the period 1935-1955 was as huge as today, as far as can be deduced from altimetry and old aereal photo’s: some 70 meter reduction of the ice sheet height at the Jacobshavn/Illulisat glacier over a few decades, going far into the main ice sheet. The current peak melt of a few days even at the summit happened too some 150 years ago, as could be measured in the Greenland ice cores. Thus there is not reason for panic, we still are within natural variability.
Melting of the ice sheet at the edges is mainly a matter of temperature. There are several stations around Greenland which show higher summer temperatures in the period 1935-1955 than current:
http://www.ferdinand-engelbeen.be/klimaat/greenland_temp.html but I need to do an update of the graph for the most recent years.
The breakup point of the largest Greenland glacier is retreating since before 1850, but there was a large retreat around 1950 and after that again advancing (together with a cooler climate) and since 1990 again a retreat. Thus nothing unusual there, simply natural variability:
http://www.ferdinand-engelbeen.be/klimaat/greenland_glacier.html

Bill Illis
August 17, 2012 11:51 am

Entropic man says:
August 17, 2012 at 9:18 am
Here is the latest most sophisticated model. It is still draft for discussion.
http://www.the-cryosphere-discuss.net/6/2789/2012/tcd-6-2789-2012.pdf

Entropic man
August 17, 2012 1:01 pm

Bill Illis says:
August 17, 2012 at 11:51 am
Here is the latest most sophisticated model. It is still draft for discussion.
http://www.the-cryosphere-discuss.net/6/2789/2012/tcd-6-2789-2012.pdf
————————————————-
They are allergic to complex models here. I think we’ll try arithmetic instead.
http://www.agu.org/pubs/crossref/2011/2009JB006847.shtml
Schrama et al 2011 used GRACE data to measure ice loss from the Greenland ice sheet. (see Figure 2). They found a loss between March 2003 and February 2010 of 1512 gigatons, 252 Gt per year.
A gigaton is one billion tons of ice, one cubic kilometre.
The surface area of Earth is 510,000,000 square kilometres of which 71% or 360,000,000sq.km. is ocean.
To raise the surface of 1 sq.km of ocean by 1mm would need 1/1,000,000 cubic kilometres of water. To raise the level of the entire ocean by 1mm would need 360,000,000/1,000,000 =360 cubic kilometres.
The annual sea level rise due to Greenland ice loss is therefore 252/360 = 0.7mm/year.
That is 4.2mm over the six years of the study.
If we accept the figure of 180mm/century quoted elsewhere, that is 1.8 mm’/year and Greenland contributes 39% of the sea level rise.
If the sceptics are right, that this melting rate is normal and will continue unchanged or even slow, we have no need to worry. If the consensus is right and ice sheet melting is due to accelerate, then we may have problems.
Oh, for a time machine!

richardscourtney
August 17, 2012 2:49 pm

Friends:
Ferdinad Engelbeen says in his fine post at August 17, 2012 at 11:03 am

The current peak melt of a few days even at the summit happened too some 150 years ago, as could be measured in the Greenland ice cores. Thus there is not reason for panic, we still are within natural variability.

The paid troll says at August 17, 2012 at 1:01 pm

If the consensus is right and ice sheet melting is due to accelerate, then we may have problems.

I say
If the consensus is right and pigs are due to learn to fly then we may need reinforced umbrellas.
Richard

Bill Illis
August 17, 2012 4:49 pm

The southern third of Greenland is too far south to have an ice-sheet. The summer solar insolation is too high to allow glaicers to build up. The only reason the ice-sheet is there is because of the ice accumulation in the centre/north during the ice ages.
If the interglacials last for 20,000 to 25,000 years, the southern third of Greenland melts out and the centre/north height will drop by 500 metres or so.
The last time this happened was the interglacial at 400,000 years ago, which was not a particularly warm one (less than current temperatures probably), and the southern third of Greenland melted out and small trees even grew there.
The Greenland ice-sheet has been shrinking since the last glacial maximum and will continue to do so for 50,000 years or even 120,000 years (when the Milankovitch Cycles turn low enough for the next ice age to begin – they don’t until then).
So, 0.3 mm/yr (the correct figure) of sea level rise was going to happen regardless of the CO2 level in the atmosphere.
That is the science .

Editor
August 17, 2012 11:18 pm

David G says:
August 15, 2012 at 5:27 pm
> Tez, the Vikings didn’t farm in Greenland for 500 years, not even close.
References?
Barry Fagan, in his “The Little Ice Age” gives 980s – mid 1300s:


They had the land to themselves, a place where the green summer pastures and thick willow scrub offered pasture and fuel. The summers were brief and fairly warm, with longer days than Iceland. The winters were long and harsh, but the Norse were accustomed to climatic extremes. They found much better grazing land than at home, abundant fish and sea mammals, and edible birds aplenty. Eirik sailed back to Iceland with glowing reports of a land so fertile he named it Greenland, “for he said that people would be much more tempted to go there if it had an attractive name.”
…..
For five centuries, Europe basked in warm, settled weather, with only the occasional bitter winters, cool summers and memorable storms, like the cold year of 1258 caused by a distant volcanic eruption that cooled the atmosphere with its fine dust. Summer after summer passed with long, dreamy days, golden sunlight, and bountiful harvests. … Nothing prepared them for the catastrophe ahead. As they labored through the warm summers of the thirteenth century, temperatures were already cooling rapidly on the outer frontiers of the medieval world.
…..
The Norse could usually survive one bad summer by using up the last of their surplus the following winter. But two successive poor hay crops placed both the animals and their owners at high risk, especially if lingering ice restricted summer hunting and fishing. The ice-core analyses for 1343 to 1362 reveal two decades of much colder summers than usual. Such a stretch, year after year, spelled disaster.
… All the dog bones at the manor farm came from the final occupation layer and displayed the butchery marks of carcasses cut up for human consumption. Having first eaten their cows and then as much small game as they could take, the Nipaatsoq families finally consumed their prized hunting dogs.
… The Norse kept a foothold at the warmer Eastern Settlement for another 150 years. …
980s to late 1200s (I left that out) + 150 = about 450 years.


Yeah, I was surprised the settlements were there for so long myself.

August 21, 2012 4:46 am

Entropic man says:
August 16, 2012 at 3:38 am

A thin layer if water would remain due to pressure melting, sufficient to provide lubrication. The same effect occurs when you ice skate; the pressure of your weight on the thin blades melts a thin film of water which reduces friction significantly.

Except that it’s not the same. Here’s a simple demo why: scatter gravel on a patch of concrete in poor condition, in sub-freezing temps. Spray with water to make a thin layer of ice. Now go skate on it.
After about the 10th severe face-plant, perhaps you’ll get it.
The rock below a glacier is no smooth, flat, prepared surface. It is jagged and debris-covered, with ridges and valleys crosscutting it. It does not permit sliding. Nohow. When a glacier moves, it GRINDS, it doesn’t “slip”.

Entropic man
August 21, 2012 9:34 am

I live in Northern Ireland, a glacially eroded landscape and see various effects.. On the hills under the original centre of the ice sheet you often get the rough surface you describe (locking the ice in place at the base but allowing it to flow nearer the surface), plus corries where a patch of ice maybe a mile across has rotated and ground a hollow beneath it.
Further out, along the paths of the glaciers, you see quite smooth surfaces on the bottom and sides of the U-shaped valleys where the material carried by the ice has ground away the surface. You even see enormous gouges where a boulder in the ice has scraped along the valley, tearing chunks away from the surrounding rock as it went. Glacial erosion can be savage!
When the ice sheet melts it leaves behind eskers, drumlins, morraines and kettleholes where material eroded along the way has been dumped by melting ice or carried in meltwater.
I love glaciers, ever since Geography classes.

Entropic man
August 21, 2012 10:50 am

Bill Illis says:
August 17, 2012 at 4:49 pm
The southern third of Greenland is too far south to have an ice-sheet. The summer solar insolation is too high to allow glaicers to build up. The only reason the ice-sheet is there is because of the ice accumulation in the centre/north during the ice ages.
If the interglacials last for 20,000 to 25,000 years, the southern third of Greenland melts out and the centre/north height will drop by 500 metres or so.
The last time this happened was the interglacial at 400,000 years ago, which was not a particularly warm one (less than current temperatures probably), and the southern third of Greenland melted out and small trees even grew there.
The Greenland ice-sheet has been shrinking since the last glacial maximum and will continue to do so for 50,000 years or even 120,000 years (when the Milankovitch Cycles turn low enough for the next ice age to begin – they don’t until then).
So, 0.3 mm/yr (the correct figure) of sea level rise was going to happen regardless of the CO2 level in the atmosphere.
That is the science .
————————————
Melting ice sheets raise sea level 1mm per 360 cubic kilometres released. (August 17th, 1.01pm).
Simplify your estimated melting to a 500M decrease in thickness across the whole ice sheet of 1,710,000sq. km.This would release 1,710,000/2 = 855,000 cu. km of water.
The sea level rise would be 855,000/360 = 2375mm or 2.375 metres.
If that happened gradually over the rest of the interglacial, say 20,000 years, the rise would be 2375/20,000 = 0.12mm/year from Greenland (entirely consistent with your 0.3mm/yr).
Unfortunately, instead of the 855000/20000 = 42.75 cu km/yr you project, the current loss rate has been measures at 252 cu.km/yr (schrama et all 2011, see my 1.01pm comment). This gives a sea level rise of 252/360 = 0.7mm/yr, over twice your figure for melting from Greenland alone.
At present the ice sheet seems to be losing mass about five times faster than your model predicts. Whether this is temporary or ongoiing is a discussion for another time.