Crack in the Earth: Greenland glacier loses ice island twice the size of Manhattan

It’s business as usual at the Petermann glacier, doing what a glacier does, calving ice into the sea. We reported on another chunk in 2010, four Manhattans in size. Borrowing from an oft used media ploy, at this rate, it will be down to ice cube size in ten years. I wonder though, if we’d ever have noticed any of this without MODIS? Keep that in mind when reading the claims.

At left An ice island twice the size of Manhattan has calved from Petermann Glacier off northern Greenland. At right, the 2010 calving, with the crack for the new chunk visible. MODIS Imagery Courtesy of Prof. Andreas Muenchow, University of Delaware from their press release

From the University of Delaware — An ice island twice the size of Manhattan has broken off from Greenland’s Petermann Glacier, according to researchers at the University of Delaware and the Canadian Ice Service. The Petermann Glacier is one of the two largest glaciers left in Greenland connecting the great Greenland ice sheet with the ocean via a floating ice shelf.

Andreas Muenchow, associate professor of physical ocean science and engineering in UD’s College of Earth, Ocean, and Environment, reports the calving on July 16, 2012, in his “Icy Seas” blog. Muenchow credits Trudy Wohleben of the Canadian Ice Service for first noticing the fracture. 

The discovery was confirmed by reprocessing data taken by MODIS, the Moderate Resolution Imaging Spectroradiometer aboard NASA’s Terra and Aqua satellites.

At 46 square miles (120 square km), this latest ice island is about half the size of the mega-calving that occurred from the same glacier two years ago. The 2010 chunk, also reported by Muenchow, was four times the size of Manhattan.

“While the size is not as spectacular as it was in 2010, the fact that it follows so closely to the 2010 event brings the glacier’s terminus to a location where it has not been for at least 150 years,” Muenchow says.

“The Greenland ice sheet as a whole is shrinking, melting and reducing in size as the result of globally changing air and ocean temperatures and associated changes in circulation patterns in both the ocean and atmosphere,” he notes.

Muenchow points out that the air around northern Greenland and Ellesmere Island has warmed by about 0.11 +/- 0.025 degrees Celsius per year since 1987.

“Northwest Greenland and northeast Canada are warming more than five times faster than the rest of the world,” Muenchow says, “but the observed warming is not proof that the diminishing ice shelf is caused by this, because air temperatures have little effect on this glacier; ocean temperatures do, and our ocean temperature time series are only five to eight years long — too short to establish a robust warming signal.”

The ocean and sea ice observing array that Muenchow and his research team installed in 2003 with U.S. National Science Foundation support in Nares Strait, the deep channel between Greenland and Canada, has recorded data from 2003 to 2009.

The Canadian Coast Guard Ship Henry Larsen is scheduled to travel to Nares Strait and Petermann Fjord later this summer to recover moorings placed by UD in 2009. These mooring data, if recovered, will provide scientists with ocean current, temperature, salinity and ice thickness data at better than hourly intervals from 2009 through 2012. The period includes the passage of the 2010 ice island directly over the instruments.

According to Muenchow, this newest ice island will follow the path of the 2010 ice island, providing a slow-moving floating taxi for polar bears, seals and other marine life until it enters Nares Strait, the deep channel between northern Greenland and Canada, where it likely will get broken up.

“This is definitely déjà vu,” Muenchow says. “The first large pieces of the 2010 calving arrived last summer on the shores of Newfoundland, but there are still many large pieces scattered all along eastern Canada from Lancaster Sound in the high Arctic to Labrador to the south.”

Prior to 2010, the last time such a sizable ice island was born in the region was 50 years ago. In 1962, the Ward Hunt Ice Shelf, on the northern coast of Ellesmere Island in Nunavut, Canada, calved a 230-square-mile island.

Article by Tracey Bryant

0 0 votes
Article Rating

Discover more from Watts Up With That?

Subscribe to get the latest posts sent to your email.

76 Comments
Inline Feedbacks
View all comments
Justthinkin
July 17, 2012 7:11 pm

OMG. That much fresh water into that cold sea water??? The narwhals and walrus’ are doomed! (but Opus is now safe).And the North Atlantic Current is fubared. And surely NYC will be under water by Xmas of this year. And all caused by an increase in temp caused by cAGW. (now where’s my grant?)

Andrew
July 17, 2012 7:27 pm

Large concentrations of Gin and Vermouth have also been observed in the area.
Mild earthquake is also predicted…just a small shaker, wouldn’t want things stirred up…

Tez
July 17, 2012 7:39 pm

There was a lot less ice in Greenland when it was being farmed by the Viking settlers. That was in the 10th Century and they stayed there for a period of 500 years or so.
The climate scientists need to find out what caused the ice to disappear all that time ago before they can reasonably discount such processes being in force now.

Byron
July 17, 2012 7:40 pm

Has it never occured to the warmists that continually growing unbroken ice sheets/glaciers would be something to get REALLY worried about

David Ross
July 17, 2012 7:52 pm

“An ice island twice the size of Manhattan has broken off from Greenland’s Petermann Glacier … At 46 square miles (120 square km), this latest ice island is about half the size of the mega-calving that occurred from the same glacier two years ago.”
For perspective, the, later mentioned, ice island that broke free from the Ward Hunt Ice Shelf, in (pre-CAGW) 1962, was 230-square-miles, so equivalent to 10 Manhattans, which is still 4 Manhattans more than the 2010 and 2012 ice islands combined.
But if we took that ice and put it in a Lake Michigan amount of whiskey and vermouth and had a maraschino cherry the size of a small moon we’d have a Manhattan to beat them all 🙂

July 17, 2012 8:03 pm

Maybe I’m just stupid but I think icebergs are nothing new. I mean, when have they ever not been in recorded history? I seem to have heard about one putting a dent into one of Man’s unsinkable things.
Point being, these glaciers have been losing pieces of themselves since before Man noticed they existed. Those pieces have been replaced at the “top” and lost at the “bottom”. But now we have pictures. And ourselves to blame it on. If only those cavemen hadn’t learned about fire!

July 17, 2012 8:25 pm

If the terminus is now at a location where it was about 150 years ago, then this is not unprecedented, right?

Christopher Simpson
July 17, 2012 8:34 pm

<iRobert Wille says:
July 17, 2012 at 8:25 pm
If the terminus is now at a location where it was about 150 years ago, then this is not unprecedented, right?
Obviously you have trouble with the meaning of words. “Unprecedented” simply means, “has never, ever happened before for at least 20 years or so.”
Seriously, though, this drives me nuts in news reports. First they say something is “unprecedented,” and in the very next sentence they’ll say that the last time it happened was such-and-such a date (generally in the ’30s or early ’40s, I notice).
We really should have an “Alarmist to Sane” dictionary.

July 17, 2012 9:00 pm

Christopher Simpson says:
July 17, 2012 at 8:34 pm
Obviously you have trouble with the meaning of words. “Unprecedented” simply means, “has never, ever happened before for at least 20 years or so.”
Seriously, though, this drives me nuts in news reports. First they say something is “unprecedented,” and in the very next sentence they’ll say that the last time it happened was such-and-such a date (generally in the ’30s or early ’40s, I notice).
We really should have an “Alarmist to Sane” dictionary.
=======================================================
Or a “When We Decide to Set The Precedent” dictionary?

July 17, 2012 9:27 pm

Upon such matters one should brood………
“The Wisconsin glacial, which preceded the Holocene, the interglacial in which all of human civilization has occurred, is littered with abrupt climate change (ACC). D-O oscillations average 1,500 years, and have the same characteristic sawtooth temperature shape that the major ice-age/interglacials do, a sudden, dramatic, reliable, and seemingly unavoidable rise of between 8-10C on average, taking from only a few years to mere decades, then a shaky period of warmth (less than interglacial warmth), followed by a steep descent back into ice age conditions. Each D-O oscillation is slightly colder than the previous one through about seven oscillations; then there is an especially long, cold interval, followed by an especially large, abrupt warming up to 16C (a Bond cycle). During the latter parts of the especially cold intervals, armadas of icebergs are rafted across the North Atlantic (Heinrich events), their passage recorded reliably by the deep ocean sediment cores which capture the telltale signature of these events in dropstones and detritus melted out of them.”
http://wattsupwiththat.com/2011/01/05/on-%E2%80%9Ctrap-speed-acc-and-the-snr/#more-30992
Of particular interest to sea-level aficionados might be this:
http://www.clim-past.net/8/1067/2012/cp-8-1067-2012.pdf
Abstract. Borehole PRGL1-4 drilled in the upper slope of the Gulf of Lion provides an exceptional record to investigate the impact of late Pleistocene orbitally-driven glacioeustatic sea-level oscillations on the sedimentary outbuilding of a river fed continental margin. High-resolution grainsize and geochemical records supported by oxygen isotope chronostratigraphy allow reinterpreting the last 500 ka upper slope seismostratigraphy of the Gulf of Lion. Five main sequences, stacked during the sea-level lowering phases of the last five glacial-interglacial 100-kyr cycles, form the upper stratigraphic outbuilding of the continental margin. The high sensitivity of the grain-size record down the borehole to sealevel oscillations can be explained by the great width of the Gulf of Lion continental shelf. Sea level driven changes in accommodation space over the shelf cyclically modified the depositional mode of the entire margin. PRGL1-4 data also illustrate the imprint of sea-level oscillations at millennial time-scale, as shown for Marine Isotopic Stage 3, and provide unambiguous evidence of relative high sea-levels at the onset of each Dansgaard-Oeschger Greenland warm interstadial. The PRGL1-4 grain-size record represents the first evidence for a one-to-one coupling of millennial time-scale sealevel oscillations associated with each Dansgaard-Oeschger cycle.

July 17, 2012 9:32 pm

We only know where Petermann Glaciers terminus was after 1875/76, because nobody was ever there to write about it before that time. The current terminus of the glacier is further back since it has ever been for the last 137 years. This is the entire observational record and the “unprecedented” refers to that time period only. We know not what it was before, that is, I can dream that there was no ice before that time and I can dream that there was ice everywhere. Either way, I have no data to confirm or deny either claim which is why I refer to this as dreaming.
Please note that the terminus in 1875/76 was seaward from where it is now, so the current location is an absolute minimum since that time. If the industrial revolution and associated prosperity and economic growth has something to do with this current minimum location, I do not know, but this is not proof for either proposition. I do know, however, that air temperatures since 1987 have been warming at a fairly steady clip, but such warming has occured in the 1920-30ies as well, so the current higher air temperatures are NOT unprecedented. Furthermore, air temperatures are largely irrelevant for Petermann Glacier, because air temperatures cause no more than 10-20% of the melting, because the oceans below this ice shelf cause 80% of the mass loss. For the ocean in and near Nares Strait and Petermann Fjord we only have records since 2003 which is NOT a climate record from which to draw conclusions regarding local, never mind, global warming.

John F. Hultquist
July 17, 2012 9:41 pm

When half of Manhattan breaks away and floats to Ireland, wake me. That would be news.

July 17, 2012 9:54 pm

I probably should have qualified my first comment on this thread. We went from 4 times Manhattan to twice in two years. Then consider Heinrich events that raft untold numbers of bergs towards the AMDO, and the signature sediments they produce. Combine that with emerging rapid sea level changes during the brief D-O events and consider viz-a-viz the present calving.

dp
July 17, 2012 9:55 pm

They’re really missing the boat on this. They should say the ice is 8 times the size of Alameda island. Alameda could use the press, too.
So what happened 150 years ago? The LIA was winding down but that had barely just started. Might it be that advances stop when everything is frozen solid and then start to move again when everything starts to thaw? That would explain why the snout was as long as it got since then. But if it is shrinking does that suggest things are cooling off and the melt and movement is slowing?

johnmcguire
July 17, 2012 10:10 pm

What was that crap about Greenland and Northwest Canada warming 5 times faster than anywhere else ? How are they producing big icebergs if they are warming ? The ice pushes to the sea and then breaks off is my understanding. Oh , they extend their fake temperature readings to there and then figure them to the thousandth degree yeah yeah , I’m sure everybody believes that.

July 17, 2012 10:28 pm

Muenchow points out that the air around northern Greenland and Ellesmere Island has warmed by about 0.11 +/- 0.025 degrees Celsius per year since 1987.
Sounds suspiciously unmeasurable, but that doesn’t prevent a nice calculation with…wait…for it…two and a half hundredths of degree accuracy! Wow! Sure is Balmy!

July 17, 2012 10:47 pm

Its an assumption that warming temperatures are causing the melt. More likely in my opinion is increased solar insolation and surface particulate deposition decreasing albedo.
Suprisingly, the nearby weather station at Eureka holds the record for the sunniest month in the world (May). This is a very sunny place in the Arctic summer.
http://www.currentresults.com/Weather-Extremes/sunniest-places-countries-world.php

Alan Clark of Dirty Oil-berta
July 17, 2012 10:50 pm

Just in time. Pour me a Glayva! Avec ice souvez plez! No but seriously, I don’t think I could care any less about the Arctic Ocean getting a bit more ice in it.

Jean Meeus
July 17, 2012 10:53 pm

“Muenchow points out that the air around northern Greenland and Ellesmere Island has warmed by about 0.11 +/- 0.025 degrees Celsius per year since 1987.”
This is a warming of 11 degrees Celsius per century. Can you really believe that?

Lew Skannen
July 17, 2012 10:55 pm

“Greenland glacier loses ice island …”
Calm down. There is no need to panic. These things always turn up eventually. Now can you remember where you last saw it?…

July 17, 2012 11:02 pm

To clarify, the particulates are deposited as the ice accumulates and become embedded in the ice. When the ice reaches the point net ice melt occurs. It melts and sublimates from the top and previously embedded particulates accumulate on the surface decreasing the albedo and increasing the amount of solar energy absorbed. So these are primarily particulates from decades, even centuries ago.

RACookPE1978
Editor
July 17, 2012 11:33 pm

Andreas Muenchow says:
July 17, 2012 at 9:32 pm
Thank you for the pleasure, promptness, and detail, of your reply! Robt

Steve R W.
July 18, 2012 12:15 am

Any threat to shipping from icebergs yet? Such as the area where the Titanic sunk.
I see nothing to worry about with this latest Greenland glacier event.
http://wattsupwiththat.com/2012/04/12/titanic-anniversary-unusual-climate-extreme-ice-conditions-tragic-accident/

Admad
July 18, 2012 12:24 am

“The Petermann Glacier is one of the two largest glaciers left in Greenland …” Weasel words, carefully chosen to enhance fears of CAGW etc.

John
July 18, 2012 12:32 am

Just to put it into perspective, if the Greenland ice sheet was as big as Manhattan, then this piece that just broke off would be the size of half a football pitch.
Send in some property developers, most of Greenland will be inhabitable soon!

1 2 3