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

Watts up with That? ^ | July 17, 2012 | Anthony Watts

[Ernest_at_the_Beach]

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

[Marine_Uncle]

I took your advice and had a drink. Actually had a few tulip glasses of wine signed off. Fired up Microsoft Flight Simulator. Loaded a mission to take off from carrier Nimitz off the Virginian Coast at Oceania NAS, flew a shorty flight plan to Willow Grove NAS in NE Philly. Landed, parked, then went to bed. Sure beats the madness on FR. :)

[thackney]

Can you even imagine the amount of shaved ice for martinis one could obtain from that hunk of ice.

If you ever tasted glacier ice, you would never consider it for consumption again.

Thousands of years of capturing bird poop, dust, etc along with the snow needed to form glacier ice makes a very nasty tasting ice/water. Sadly, I know this from direct experience. My mouth is puckering up now just remembering the experience from years ago.

[Marine_Uncle]

Yo Thack. Good points. Well taken.

[thackney]

I remember rafting just downstream of the Matanuska Glacier in Alaska. There were so many minerals in the water that it was liquid at 28°F. Glacier fed rivers are gray compared to the clear streams that join them. A glacier is one of the least pure natural sources of water.

[thackney]

[Marine_Uncle]

RE: "A glacier is one of the least pure natural sources of water."
Understand. Nice picture as well. I have never been to the great state of Alaska.

[thackney]

I just though of something. The “taste” may be worse in Alaska. Glaciers in an area with active volcanoes are going to capture ash in that compacted snow.

If you ever get to see the front edge of a glacier on land, you might be surprised how filthy it is. Those that calve into water are not so bad, but if it completely melts down on land, the gravel, etc that was accumulated is concentrated down as much of the ice melts away. Lighter stuff was already carried away with the melting, but the leading edge is full of stuff that is harder for water to carry.

[Marine_Uncle]

Sulfur compounds, as well. I have witnessed similar scenes in eastern states in mountainous, ski areas, where clear streams where turned to milk white, which normally where very clear say free stoners. Especially during spring melts.

[bkepley]

Rope that calve and take it to Texas.

[OneVike]

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

In other words, the planet is doing what it has always done, replenish itself through a cyclical process that has been going on from the beginning of time when God created it.

The lack of historical perspective that is presented to the readers in articles written about earthly common events like this always brings to mind the phrase, "Some people are educated beyond their intelligence"

These ignoramuses truly lack wisdom. Without it, they will never be able to understand that which is as plain as the nose on their face.

[Ernest_at_the_Beach]

I went to bed and the next day when I got on the internet ...FR wasn't responding....so I worked on my puter...

But got to leave again....be back much later.

[presently no screen name]

.....>But got to leave again....be back much later.<

You like the beach more than you like us!! :)

Here’s something to make the day complete with some laughs!

http://www.freerepublic.com/focus/f-news/2908410/posts

[presently no screen name]

the planet is doing what it has always done, replenish itself through a cyclical process that has been going on from the beginning of time when God created it.

Exactly! And GREAT POST!