Tornado Alley (PROG)

[F6]

Glacial Change Ain’t What It Used To Be: Petermann Calves Another Huge Chunk of Greenland Ice


Petermann Glacier has calved another gigantic ice island, larger than twice the size of Manhattan, not quite as large as the calving of two years ago [ http://neven1.typepad.com/blog/2010/08/animation-10-petermann-glacier-ice-tongue.html ]. A study this month found that the melting of the Greenland Ice Sheet is nearing a critical “tipping point [ http://thinkprogress.org/climate/2012/07/01/508782/greenland-ice-sheet-melt-nearing-critical-tipping-point/ ].”

by Neven, via the Arctic Sea Ice Blog [ http://neven1.typepad.com/blog/2012/07/petermann-calves-again.html ]
Jul 16, 2012 at 6:14 pm

This second big calving (spotted this time by Arcticicelost80 [ http://neven1.typepad.com/blog/2012/07/asi-2012-update-7-steady-as-she-goes.html?cid=6a0133f03a1e37970b017616814b20970c#comment-6a0133f03a1e37970b017616814b20970c ]) is another spectacular event on Greenland, after retreats of the Jakobshavn Glacier and lowest reflectivity of the Greenland ice sheet on record (see blog post [ http://neven1.typepad.com/blog/2012/07/the-dark-side-of-greenland.html ]), leading to unprecedented flooding [ http://neven1.typepad.com/blog/2012/07/the-wet-side-of-greenland.html ] in the southwest of Greenland.

From the Icy Seas blog [ http://icyseas.org/2012/07/16/new-petermann-ice-island-forming-july-16-2012/ ]:

This morning Petermann Glacier lost another ice island….



The break-off point has been visible for at least 8 years in MODIS imagery propagating at speeds of 1 km/year towards Nares Strait. The fracture also extended further across the floating ice sheet from the northern towards its southern side.

This event is still evolving, Trudy Wohleben of the Canadian Ice Service noticed it first (as in 2010) after reviewing MODIS imagery. Several people in several countries are monitoring and assessing the situation, but a first estimate of its size is 200 km^2 (3 Manhattans), I will revise this figure as soon as I got my hands on the raw data.

Read more here [ http://icyseas.org/2012/07/16/new-petermann-ice-island-forming-july-16-2012/ ].

Two years ago Patrick Lockerby was the first to tell the world [ http://www.science20.com/chatter_box/arctic_newsflash_petermann_ice_tongue_loses_huge_chunk ] about the big calving that occurred at Petermann Glacier [ http://en.wikipedia.org/wiki/Petermann_Glacier ]. The Arctic Sea Ice blog followed suit [ http://neven1.typepad.com/blog/2010/08/animation-10-petermann-glacier-ice-tongue.html ] shortly afterwards. The whole event garnered a lot of attention, popularizing the island of Manhattan as an area measurement tool (metre, kilometre, Manhattan). This second big calving in as many years doesn’t come as a surprise, as attested by this article [ http://green.blogs.nytimes.com/2011/08/31/documenting-a-collapsing-ice-shelf/ ] on the New York Times blog from August last year:

Thanks to satellites and other instruments, researchers do know what is happening to ocean and air temperatures in northwest Greenland. They have been warming briskly of late, as global-warming theory predicted decades ago that they would for the whole Arctic.

Dr. Box finds a drastic increase in sea-surface temperatures in the region, and a sharp decline in sea ice. Scientists suspect that warmer water is circulating under Greenland’s floating ice shelves and causing them to weaken. But given the dearth of measurements from beneath Petermann, they do not have hard proof that is what happened in this case.

The breakup of the Petermann ice shelf fits into a broader picture. Many lines of evidence suggest that melting and breakup of Greenland ice, a phenomenon once concentrated on the southern end of that island, has spread to the colder northwest corner. As I reported [ http://www.nytimes.com/2010/11/14/science/earth/14ice.html ] last year, many scientists are worried about the overall fate of the Greenland ice sheet, especially the prospect that its melting could raise global sea levels substantially.

(…)

Dr. Box said another chunk of the Petermann Glacier, this one about twice the size of Manhattan, is now on the verge of breaking loose.

Dr. Box was right. He can now add another image to these two he posted on the blog [ http://bprc.osu.edu/wiki/Petermann_Glacier_before-after-photos_2010-2011 ] of the Byrd Polar Research Center blog last year:

In response to the question: How abnormal is this event? Jason notes: “The August 2010 ice calving at Petermann is the largest in the observational record for Greenland” Falkner et al. (2011) scoured the observations and found no evidence of an event this large in scattered observations since 1876. Johannessen et al. (2011) identified the next largest observed Petermann calving event ocurring in 1991, being 58% as large as the 2010 event.

Another image can be added to these two posted in the same BPRC blog post (check out the little Eiffel towers on the left that give an idea about this mamma’s magnitude):



When it comes to those “dearth of measurements” mentioned in the article, Andreas Münchow, a sea-going physical oceanographer from the University of Delaware, is supposed to go to Nares Strait (here [ http://icyseas.files.wordpress.com/2012/06/t2012162nares2.png?w=500&h=615 ] to be precise) on the Canadian Coast Guard Ship Henry Larsen at the beginning of August to retrieve instruments that have recorded ocean current, temperature, salinity, and ice thickness data at better than hourly intervals from 2009 through 2012. As Dr. Münchow says in a comment following the blog post I alluded to at the top:

I am crunching numbers … this is a very worrisome event that will make our lives to get a ship recover our instrumentation more challenging and risky. I hope that this ice island will stay inside the fjord until we have safely entered and exited Nares Strait the first 2-3 weeks in August.

– Neven writes for the Arctic Sea Ice Blog. This is an excerpt of a piece originally published at the Arctic Sea Ice Blog [ http://neven1.typepad.com/blog/2012/07/petermann-calves-again.html ] and was reprinted with permission.

*

Related Climate Progress posts:

Unprecedented May Heat In Greenland, Temperature Hits Stunning 76.6°F
http://thinkprogress.org/climate/2012/06/04/494641/unprecedented-may-heat-in-greenland-temperature-hits-stunning-766f/

Greenland Ice Sheet “Could Undergo a Self-Amplifying Cycle of Melting and Warming … Difficult to Halt,” Scientists Find
http://thinkprogress.org/climate/2011/10/24/351570/greenland-ice-sheet-melting-warming/

*

Copyright 2012 Arctic Sea Ice Blog (emphasis in original)

http://thinkprogress.org/climate/2012/07/16/525251/glacial-change-aint-what-it-used-to-be-petermann-calves-another-huge-chunk-of-greenland-ice/ [with comments]


===


Biggest Greenland glacier break-up

Uploaded by newscientistvideo on Sep 29, 2011

Read more:
http://www.newscientist.com/blogs/nstv/2011/09/time-lapse-tuesday-biggest-greenland-glacier-break-up.html

http://www.youtube.com/watch?v=XeYHzu_bW6M


===


Record Amount of Arctic Sea Ice Melted in June, Plus Amazing Video Of Greenland Ice Melt

Andrew Freedman, via Climate Central [ ]
Jul 15, 2012 at 12:20 pm

The Arctic melt season is well underway, and sea ice extent — a key indicator of global warming — declined rapidly during June, setting a record for the largest June sea ice loss in the satellite era. Sea ice extent is currently running just below the level seen at the same time in 2007, the year that set the record for the lowest sea ice minimum in the satellite era.


Arctic sea ice extent as of July 12, plus daily extent data for 2007 record melt season. Gray area around the average line shows the two standard deviation range.
Credit: NSIDC.

While the current rate of sea ice decline does not necessarily indicate that another record low will be set this year — weather conditions and other factors could slow the melt before the September sea ice minimum — so far the 2012 melt season has continued the trend of accelerated sea ice loss in the Far North.

According to the National Snow and Ice Data Center (NSIDC) in Boulder, Colo., large amounts of sea ice loss were observed during June in the Beaufort, Bering, and Kara Seas as well as Baffin and Hudson Bay. The only area with above average sea ice at the end of June was the eastern Greenland coast, the NSIDC stated.

During June, the Arctic lost a record total of about 1.1 million square miles of ice — an area about as large as the combined land area of Alaska, California, Florida, and Texas. At the end of the month, Arctic sea ice extent was 456,000 square miles below the 1979-to-2000 average. The past three years have seen the lowest June ice extents on record, and this year, sea ice loss is running about three weeks ahead of schedule. The ice extent recorded for June 30 would normally be expected on July 21, based on the 1979-2000 average, the NSIDC said.


Northern Hemisphere June snow cover anomalies, showing the record low in 2012. Credit: NSIDC.

Warmer-than-average air temperatures and a lack of snow cover helped speed the melt, according to the NSIDC. In its July 5 analysis, the NSIDC reported that a record low Northern Hemisphere snow cover extent was set for the month of June.

“This rapid and early retreat of snow cover exposes large, darker underlying surfaces to the sun early in the season,” the NSIDC reported, “fostering higher air temperatures and warmer soils.”

In general, the Arctic has been warming at a rate about twice that of lower latitudes, a trend that is expected to continue due to feedbacks in the Arctic climate system. For example, when sea ice melts, the darker ocean surface is exposed to incoming solar radiation. This warms the water and the air much more than if the brighter sea ice had remained.

Recent research has demonstrated that rapid Arctic climate change is altering the flow of weather systems across the Northern Hemisphere, raising the possibility of far-reaching consequences well south of the Arctic Circle. Increased summer sea ice loss is also helping to open the Arctic to oil and natural gas drilling, as well as increased shipping activities, which could cause further changes to the Arctic environment.

Andrew Freedman is the Senior Science Writer for Climate Central. This piece was originally published at Climate Central and is reprinted with permission.

Copyright 2012 Climate Central

*

JR: What follows are videos [ http://www.youtube.com/watch?v=RauzduvIYog ; http://www.youtube.com/watch?v=7SuJ1sFn_B0 ] and excerpt from Neven’s Arctic Sea Ice Blog [ http://neven1.typepad.com/blog/2012/07/the-wet-side-of-greenland.html ]:

The Wet Side of Greenland

by Neven

When writing The dark side of Greenland [ http://neven1.typepad.com/blog/2012/07/the-dark-side-of-greenland.html ], a recent blog post on decreasing reflectivity of the Greenland ice sheet, with images comparing the southwest of Greenland with satellite images from previous years, I of course realized that when that ice sheet becomes less reflective, it will soak up more solar energy and thus melt faster. But the practical aspect of this theory never really dawned on me, until I saw this video [above].

Levels in the Akuliarusiarsuup Kuua [ http://en.wikipedia.org/wiki/Akuliarusiarsuup_Kuua ] river, also knows as the Watson river, have reached such heights that they have smashed the two bridges connecting the north and south of Kangerlussuaq [ http://en.wikipedia.org/wiki/Kangerlussuaq ], a small settlement in southwestern Greenland, located at the head of the fjord of the same name. The river water stems from different meltwater outflow streams from Russell Glacier [ http://en.wikipedia.org/wiki/Russell_Glacier ] (an outflow of the Greenland ice sheet), and is a tributary of Qinnguata Kuussua [ http://en.wikipedia.org/wiki/Qinnguata_Kuussua ], the main river in the Kangerlussuaq area.

Of course the local media are covering the story. Here are a few excerpts from different news articles [ http://sermitsiaq.ag/node/131149 ] from Sermitsiaq (via Google translate):

What has happened in detail over the inland ice, which caused this incident, is not yet known, but the fierce heat has certainly been an important player. And unfortunately it looks like the weather will not come to the Greenlanders’ rescue, as the air temperatures over the ice sheet are expected to remain warmer than normal at least the next 7-10 days, writes Greenland meteorological Jesper Eriksen at dmi.dk.

However, it’s not only hot on the icecap at Kangerlussuaq. Deep in the ice, there are also plus degrees:

In Greenland, it has been very hot over the inland ice in comparison to normal conditions. On July 11th at 15 UTC the recorded temperature at the Summit Camp weather station, which is located at the ice cap’s highest altitude (3200 metres), was 2.2 degrees Celsius. That is quite high for this height, particularly in light of the fact that ice has a relatively high albedo.

Just 2.2 °C doesn’t sound like much (although it looks to be a new record [ http://www.wunderground.com/history/station/04416/2012/7/13/MonthlyHistory.html?req_city=NA&req_state=NA&req_statename=NA ] for July), until one realises that we are talking Summit Camp [ http://www.summitcamp.org/ ] here. At an altitude of 3200 metres. In the middle of the Greenland ice sheet. Nothing but ice.

3.5 million liters of water pressed through the narrow river every second. It’s almost a doubling of previous records. It’s no wonder that a 20 ton wheel loader was torn away from the bridge in Kangerlussuaq like a toy [second, shorter vid just above].

Copyright 2012 Arctic Sea Ice Blog (emphasis in original)

JR: The rest of Neven’s post is here [ http://neven1.typepad.com/blog/2012/07/the-wet-side-of-greenland.html ].

*

http://thinkprogress.org/climate/2012/07/15/517681/record-amount-of-arctic-sea-ice-melted-in-june/ [with comments]


===


Must see video of Greenland melting (2009.02.20)

Uploaded by starrdreams on Mar 5, 2009

Source: http://www.telegraph.co.uk/earth/environment/climatechange/4734859/Scientists-capture-dramatic-footage-of--Arctic-glaciers-melting-in-hours.html

http://www.youtube.com/watch?v=3F9FbdqGRsg


===


Melting Trends: Arctic Ice Completely Gone by 2020?

Uploaded by ForaTv on Aug 31, 2009

Complete video at: http://fora.tv/2009/08/18/A_REALLY_Inconvenient_Truth_Dan_Miller

Environmentalist Dan Miller discusses images of arctic ice melting trends at the North Pole. He argues that light once reflected off the surface of the melting ice is now being absorbed by water, priming a feedback loop that will continuously accelerate the melting process.

Dan Miller's presentation focuses on why the UN IPCC (Intergovernmental Panel on Climate Change) reports are actually best case scenarios. For example, IPCC climate models do not include the effect of melting permafrost releasing greenhouse gases, even though the permafrost is melting now and it holds more greenhouse gases than all that mankind has ever released.

Another example is that IPCC predictions of sea level rise only take into account thermal expansion of the oceans and melting of glaciers; the largest factor, disintegration of glaciers, was not included because it is hard to model. The result is that sea level rise will likely be substantially higher this century than the IPCC predicts.

Miller discusses several other potential catastrophes that are not included in IPCC predictions and also discusses tipping points that could put climate change solutions out of our reach in years or decades, the psychology of climate change, and why it is difficult for people to respond to the threat posed by a warming earth.

His talk concludes with a discussion of ways to address climate change and the risks and opportunities that companies face due to the climate crisis. - Berkeley Cybersalon

Dan Miller is Managing Director of the Roda Group. He is the former president of Ask Jeeves, Inc., a Roda Group affiliate company. He is currently working with a number of Roda Group affiliated companies to assist them with their business development efforts. Mr. Miller sits on the Board of several Roda Group companies.

At the end of 1994, Mr. Miller retired from his position as Executive Vice President of TCSI Corporation (Nasdaq: TCSI), a company he co-founded with his Roda Group partner, Roger Strauch. Mr. Miller retired from the Board of Directors of TCSI in June of 1997. TCSI is a leading provider of integrated software products and services for the global telecommunications industry.

Prior to TCSI, Mr. Miller was a systems engineer at Hughes Aircraft's Space and Communications Group where he was responsible for designing communications payloads for commercial communications satellites.

http://www.youtube.com/watch?v=cqjO8rwB-GI


===


(linked in):

http://investorshub.advfn.com/boards/read_msg.aspx?message_id=41221897 (earlier this string) and preceding and following

http://investorshub.advfn.com/boards/read_msg.aspx?message_id=59369237 and preceding and following

http://investorshub.advfn.com/boards/read_msg.aspx?message_id=66163504 and preceding and following

http://investorshub.advfn.com/boards/read_msg.aspx?message_id=69813178 and preceding and following

http://investorshub.advfn.com/boards/read_msg.aspx?message_id=70063182 and preceding and following

http://investorshub.advfn.com/boards/read_msg.aspx?message_id=71892998 and preceding and following

http://investorshub.advfn.com/boards/read_msg.aspx?message_id=77611326 and preceding and following