From the European Space Agency (ESA):
Satellite observes rapid ice shelf disintegration in Antarctic
5 April 2012
As ESA’s Envisat satellite marks ten years in orbit, it continues to observe the rapid retreat of one of Antarctica’s ice shelves due to climate warming.
One of the satellite’s first observations following its launch on 1 March 2002 was of break-up of a main section of the Larsen B ice shelf in Antarctica – when 3200 sq km of ice disintegrated within a few days due to mechanical instabilities of the ice masses triggered by climate warming.
Now, with ten years of observations using its Advanced Synthetic Aperture Radar (ASAR), Envisat has mapped an additional loss in Larsen B’s area of 1790 sq km over the past decade.
The Larsen Ice Shelf is a series of three shelves – A (the smallest), B and C (the largest) – that extend from north to south along the eastern side of the Antarctic Peninsula.
Larsen A disintegrated in January 1995. Larsen C so far has been stable in area, but satellite observations have shown thinning and an increasing duration of melt events in summer.
“Ice shelves are sensitive to atmospheric warming and to changes in ocean currents and temperatures,” said Prof. Helmut Rott from the University of Innsbruck.
“The northern Antarctic Peninsula has been subject to atmospheric warming of about 2.5°C over the last 50 years – a much stronger warming trend than on global average, causing retreat and disintegration of ice shelves.”
Larsen B decreased in area from 11512 sq km in early January 1995 to 6664 sq km in February 2002 due to several calving events. The disintegration in March 2002 left behind only 3463 sq km. Today, Envisat shows that only 1670 sq km remain.
Envisat has already doubled its planned lifetime, but is scheduled to continue observations of Earth’s ice caps, land, oceans and atmosphere for at least another two years.
This ensures the continuity of crucial Earth-observation data until the next generation of satellites – the Sentinels – begin operations in 2013.
Credits: ESA
“Long-term systematic observations are of particular importance for understanding and modelling cryospheric processes in order to advance the predictive capabilities on the response of snow and ice to climate change,” said Prof. Rott.
“Climate models are predicting drastic warming for high latitudes. The Envisat observations of the Larsen Ice Shelf confirm the vulnerability of ice shelves to climatic warming and demonstrate the importance of ice shelves for the stability of glaciers upstream.
“These observations are very relevant for estimating the future behaviour of the much larger ice masses of West Antarctica if warming spreads further south.”
Radars on Earth observation satellites, such as Envisat’s ASAR, are particularly useful for monitoring polar regions because they can acquire images through clouds and darkness.
The Sentinel missions – being developed as part of Europe’s Global Monitoring for Environment and Security (GMES) programme – will continue the legacy of radar observations.
That’s all very nice, but Antarctic sea ice is above average now and has been for a while.
Isnt this classic cherry picking. Southern Hemisphere ice is above normal.
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seaice.anomaly.antarctic.png
“The northern Antarctic Peninsula has been subject to atmospheric warming of about 2.5°C over the last 50 years – a much stronger warming trend than on global average, causing retreat and disintegration of ice shelves.”
I’m no climate scientist, so the above quote leaves me with the following question: How exactly does CO2 cause the northern Antarctic Peninsula to warm up more than the rest of the world? Shouldn’t CO2 be warming the world more uniformly, if indeed it is doing it at all?
What we see occurring at both Poles and in the Himalayas are changes equivalent to the “canary in the cage” phenomena. A very real danger is that the muskeg in the North will also melt releasing vast quantities of methane and CO2. Should this occur warming will accelerate even more rapidly than at present.
Do these people have no shame?
Antarctic ice has performed opposite predictions, yet the same tripe is repeated over and over.
“Ice shelves are sensitive to atmospheric warming and to changes in ocean currents and temperatures,” said Prof. Helmut Rott from the University of Innsbruck.
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Then they are also sensitive to cold…..what made them in the first place, in a place that would be the most unstable for ice shelves?
…that has the be the stupidest place in this whole world to put floating ice shelves
so what made them form there in the first place
I thought that was called calving? Maybe because the Arctic isn’t cooperating, it’s time to look South.
So all by itself the same satellite that tells us sea level is falling
is also telling us that ice loss is ‘rapid’ and ‘due to climate change’?
‘Rapid’ by what measure? ‘Due to’ according to whom?
Gee, here I was thinking satellites sent signals that we interpet as data,
but I was so wrong. They talk, preaching the dangers of global warming!
More crock in the Antarctic.
“…when 3200 sq km of ice disintegrated within a few days due to mechanical instabilities of the ice masses triggered by climate warming.”
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Since ice shelves have a habit to move, it can not be so simple attributed to warming. A warm weather can cause some melting on the surface, naturally, but not “mechanical instabilities of the ice masses”. Even the biased Wikipedia has something different about “mechanical instabilities”: “Ice shelves are principally driven by gravity-driven pressure from the grounded ice [1] That flow continually moves ice from the grounding line to the seaward front of the shelf.” (http://en.wikipedia.org/wiki/Ice_shelf)
Also interesting is, that the pictures of the animation are SUMMER pictures. January is the warmest month there: “Because the Antarctic Peninsula, which reaches north of the Antarctic Circle, is the most northerly part of Antarctica, it has the mildest climates within this continent. Its temperature are warmest in January, averages 1 to 2°C, and coldest in June, averages from -15°C to – 20°C. Its west coast from the tip of the Antarctic Peninsula south to 68 degrees South, which has a maritime Antarctic climate, is the mildest part of Antarctica Peninsula. Within this part of the Antarctic Peninsula, temperatures exceed 0°C for 3-4 months during the summer, and rarely fall below -10°C during the winter.” (http://en.wikipedia.org/wiki/Antarctic_Peninsula#Climate)
“Climate models are predicting drastic warming for high latitudes.
Just once, I wish these sorts of doom articles would reference a specific model, developer source, run date(s) and how predictions are derived from run output.
Are you listening, Prof. Rott ? ?
We’ve seen with the Wilkins ice bridge breakup that a large ocean swell over a period of week can lift and drop a shelf, causing a mechanical breakup that has nothing to do with temperature. This might well be the same. We’d need a time lapse series of photos to be sure.
A bunch of pathetic liars playing with a satellite.
Love the pictures, hate the lies.
Want 50% of the money back.
The Antarctic sea ice anomaly is up 0.472 milliom sq. kilometres so I do no see much signs of melting there. That’s a lot of new ice by any meansure. When things get too big they just crack off bits at the edge.
Someone does definitely seem to be on crack here to judge by the quality of the article. Hugh Pepper and his canary in the cage are definitely two of them.
These days almost everything is rapid, unprecedented, catastrophic and due to Global Warming, even if the temperatures are generally going down. Down is the new Up. We are getting very bored with the vapid nature of it all and are beginning to tire of the stupidity.
I take it.that these satellite records are the first covering this area and there are no such records prior 2002 to make comparison with? Yet observed history since explorers first discovered the Antartic suggests the outer ice shelf has variously advanced and retreated over that relatively short period.
The fact this new satellite record of retraction occurred over the 10 years that the measured average temperature of our planet has NOT risen must suggest some explanation other than to blame ‘global warming’? Please explain?
Hmmmm — can you say end of summer melt season, and Antarctic ice is currently above the long term average.
News flash ice shelves just like glaciers terminating in the sea are constantly calving ice bergs this has been going on for millions of years.
As indicated by the following article these huge ice bergs are nothing new (or unusual)
http://www.usatoday.com/weather/resources/coldscience/2005-01-20-1956-antarctic-iceberg_x.htm
1956 size 12,000 sq miles 208×60 miles
Yet if you look for “largest iceberg ever recorded” on wikipedia you will see no mention of this gargantuan ice berg, as they claim the largest ever recorded is the berg named B-15 which is approximately 1/2 the size of the 1956 berg at 183×23 miles, with a surface area of 11,000 km² (6,835 mi²)
https://en.wikipedia.org/wiki/Iceberg_B-15
Mighty convenient to not mention the much larger 1956 berg and pretend it did not happen.
There is also no legitimate reason to believe the 1956 berg was the largest possible prior to modern observation methods.
Get over it guys, this is nothing new or in the least bit unusual!
Larry
Could someone give me a scientifically defensible reconciliation of the Antarctica ice shelves retreat and the SH Sea Ice anomaly being above average per Joe Bastardi link. To this simple mind one doesnt follow the other.
Just to be sure the USA today report linked to above does not get “disappeared”
Source : http://www.usatoday.com/weather/resources/coldscience/2005-01-20-1956-antarctic-iceberg_x.htm
“Antarctica shed a 208-mile-long berg in 1956
One of the largest known Antarctic icebergs broke off in 1956. Julie Palis and Guy Guthridge of the Naitonal Science Foundation and Lyn Lay, the librarian at Byrd Polar Research Center, found an article about it in the Polar Times, vol. 43, page 18.
Here is the entire text:
“A record iceberg seen in Antarctic
“Little America V, Antarctica, Nov. 17- The U.S.S. Glacier, the Navy’s most powerful icebreaker, has sighted an iceberg more than twice the size of Connecticut.
“The berg was sighted by the Glacier early this week about 150 miles west of Scott Island. The ship reported it was 60 miles wide and 208 miles long- or more than 12,000 square miles, as against Connecticut’s 5,009.
“According to the United States Navy sailing directions for Antarctica, the largest berg hitherto reported was that seen Jan. 7, 1927, off Clarence Island by the Norwegian whale catcher Obb I. The ship said it was 130 feet high and roughly 100 miles long. Both these gargantuan icebergs were of the tabular variety typical of Antarctica. This type consists of a section of continental ice sheet that has pushed out a great distance over the sea before breaking off – a situation that does not arise in the Arctic. The tabular berg has a flat top and is of uniform height, drawing roughly 700 feet of water.
“It was the “calving” that is, breaking off, of such an immense wafer of ice at the Bay of Whales sometime between 1948 and 1955 that deprived the original Little America of its harbor. Hence this camp, built early this year, had to be set up on Kainan Bay, thrity-five miles to the east.”
Correct me if I am mistaken but this is sea ice, thus afloat on the water. Melting would then occur from below (the water being warmer than 0 C) and above when air temperatures or absorption due to low albedo are suitable. However the breaking up of thick ice is mostly a mechanical process driven by ice mass, leverage, collision with already broken-off ice bergs, sea level and waves. Melting to my mind plays a very minor role apart from weakening stress points.
Hugh Pepper says:
With ice at both poles increasing (go farther up and catch Bastardi’s comment), you let us know when that melting to release methane and CO2 occurs, Hugh. And the obvious thing is, Hugh, Bastardi has 1,000 times the credibility you have!
Hugh–why do you even post such nonsense? Are you paid to do it? Are you a member of “The Team” pitching “The Cause” because….
BECAUSE?
The frame dated 19 Jan 2008 in the animated gif looks like Larsen A and B recovered somewhat for a short while yet all they seem to mention is retreat.
Just hold the phone here. My crystal ball is just as good as these guys so why arn’t they paying me the big bucks too?
A relatively thin brittle sheet of crystal H2O forms over a surging ocean. It shatters into various sized pieces that float, melt, refreeze and make for pretty pictures. Other than the last aspect there is nothing to get excited about.
http://img.dailymail.co.uk/i/pix/2008/03_03/Berg2ALAMY1802_800x533.jpg
“What we see occurring at both Poles and in the Himalayas are changes equivalent to the “canary in the cage” phenomena. ”
Yup, just like a canary in a cage…Perfectly normal.
” A very real danger is that the muskeg in the North will also melt releasing vast quantities of methane and CO2. Should this occur warming will accelerate even more rapidly than at present.”
not at all + acceleration….. Terrifying.
Hugh Pepper says:
April 5, 2012 at 3:52 pm
Should this occur warming will accelerate even more rapidly than at present.
This reply is NOT meant to convince Hugh Pepper of anything but to clarify things for new people that may be on this site and who may be wondering what is going on here. My concern is that if statements like the above are not challenged, people may believe them to be true. The above statement is almost like being asked if you are still beating your wife. So here are the facts as I see them:
1. It is NOT warming at the present time.
2. Since it is not warming, there is no acceleration in the warming.
3. Since there is no acceleration in the warming, it cannot accelerate even more rapidly.
See the following for the last ten years.
http://www.woodfortrees.org/plot/wti/from:1995/plot/wti/from:2002/trend/plot/hadsst2gl/from:1995/plot/hadsst2gl/from:2002/trend
The green downward sloping line is the average of four different data sets over the last ten years. The purple downward sloping line is the average of sea surface temperatures over the last ten years. So it has been cooling over the last ten years.