Antarctic ice sheets melting at ever-faster rate due to global warming: new study

Sun, 2008-01-20 12:20Bill Miller
Bill Miller's picture

Antarctic ice sheets melting at ever-faster rate due to global warming: new study

The report in last week’s Nature Geoscience, which builds on previous findings, lends greater urgency to the search for a new global agreement to limit greenhouse emissions.

Nature Geoscience has concluded that changes in water temperature and wind patterns due to global warming are melting ice sheets in western Antarctica at a much faster rate than previously detected.

Using measurements from satellites that scanned about 85 percent of Antarctica’s coasts from 1996 to 2006, the study’s authors found that West Antarctica has been losing ice 60 percent faster than 10 years ago.

While ice loss is still rather small compared with Antarctica’s vast ice sheets, the study said if the trend continues global sea levels could raise higher and more swiftly than previously supposed.

A report by the British Antarctic Survey, itself based on earlier work completed in 2005, registered a 12% increase in melting from 1993 to 2003 and concluded that eighty-seven percent of glaciers have been retreating and are now actually speeding up. The Antarctic Peninsula, moreover, has warmed by nearly 3C over the last half-century.

The Intergovernmental Panel on Climate Change has predicted if nothing is done to slow the increase in global-warming gases, the world’s oceans could rise as much as two feet this century. Many scientists add another foot because they think the panel underestimated glacial flows.

How much the Antarctic melting will add is still anybody’s guess, but the new findings are yet another sign that there is no way to deny global warming.

Previous Comments

This study appears to refer to the western Antarctic only which has seen some melting for years. The Antartica on whole appears to be gaining mass.

Overall, the southern hemisphere has 1,000,000 square kilometers more of sea ice then it did last year, and is well above average for the last 28 years.

http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/current.365.south.jpg

http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/current.anom.south.jpg

The study deals with the whole of Antarctica (except for a small part not covered adequately by satellite) for the first time. That is why it is so important. And the data is much more accurate than that used in previous studies. The specific information about the western area where loss is highest is featured, but that isn’t the only area covered by the study. They also found that increase from snow is negligible.

Not only is the ice mass shrinking, the rate of ice loss has increased by a whopping 75% over 10 years (from 1996-2006). Lead author Eric Rignot is quoted in the Globe & Mail: “I see [global warming] as the main driver for the change in ice mass. And this means that we are not in a natural cycle, but in something that is related to global warming or global climate change, whichever you want to call it.” The G&M story is at: http://www.theglobeandmail.com/servlet/story/RTGAM.20080113. [space inserted]wicesheet13/BNStory/National/home

The original paper is being published in a new journal in the Nature group, Nature Geoscience, here: http://www.nature.com/ngeo/index.html. But of course the paper itself is firewalled.

This study is particularly important because the 4th IPCC scenarios reckoned in the Greenland ice loss, but when they went to press there was no clear picture of what was happening at the other pole. Apparently the impact on sea level rise of what Rignot et al have found will be as significant as what’s happening in Greenland.

The issue of sea ice is a completely separate one, and is a seasonal variation, not part of the long-term land-based ice sheet loss.

Fern Mackenzie

Paul S, once again you show your lack of respect for scientists by choosing to believe what you find on the anti-science sites rather than checking what is being reported in the scientific literature.

The report which is described in the Nature paper supports the results carried out by the GRACE group, which measures total mass of the ice. The Nature paper measures the speed at which the ice is moving, the faster it moves seaward the faster it will disappear.

Sea ice extent really has very little to do with the mass of ice in Antarctica since a lot of thinner ice is is not as important has the total volume of ice.

The two graphs you refer us to are for sea ice and not total ice. Total ice, now determined by two completely different methods, GRACE and satellite interferometric synthetic-aperture radar, both show much more rapid loss of ice than had previously been thought.

Ian Forrester

Climate obviously has changed and will continue to change. The observation that ice is melting, which can look dramatic on TV, does not show that human activity is the cause. The assertion that humans are or ever can have a significant influence on climate by limiting the use of fossil fuel (a.k.a. limiting human production of carbon dioxide) is not supported by any historical record. The only implication that carbon dioxide level has a significant effect on climate comes from huge but still incomplete computer programs that attempt to predict future climate.

Avoid the group-think and de facto censorship by Climate Scientists. Directly interrogate official government data that taxpayers have paid for from ORNL and NOAA as follows:

If the carbon dioxide level from Lawdome, Antarctica http://cdiac.ornl.gov/ftp/trends/co2/lawdome.combined.dat is graphed on the same time scale as fossil fuel usage from http://cdiac.ornl.gov/trends/emis/tre_glob.htm it is discovered that the current carbon dioxide level increase started about 1750, a century before any significant fossil fuel use.

If average earth temperature since 1880 from http://www.ncdc.noaa.gov/oa/climate/research/anomalies/anomalies.html is graphed on the same time scale as fossil fuel use it is discovered that there is no correlation between rising fossil fuel use and average global temperature at least until 1976.

The asserted hypothesis that, since 1976, increasing carbon dioxide level has caused the temperature to rise is refuted by the carbon dioxide level from http://cdiac.ornl.gov/trends/co2/vostok.html and earth temperature from http://cdiac.ornl.gov/ftp/trends/temp/vostok/vostok.1999.temp.dat determined from the Vostok, Antarctica ice cores. If these are graphed on a higher resolution time scale it is discovered that the change in atmospheric carbon dioxide level lags earth temperature change by hundreds of years.

If Lawdome and recent carbon dioxide data and Vostok and recent temperature are plotted on the same graph since 1000 AD (or before) it is observed that temperature oscillates up to plus or minus 1.5 degrees Celsius (half pitch about 100 yr) while carbon dioxide level remains essentially unchanged (between 9000BC and 1750AD). This will also show that the average global temperature 200 years ago was about the same as now, 400 years ago was significantly higher than now and current rate of temperature change is fairly typical. Recent measurements show that average earth temperatures in 2006 and 2007 were actually lower than in 1998.

For most of the history of earth carbon dioxide level has been several times higher than it is at the present as shown at http://www.geocraft.com/WVFossils/Reference_Docs/Geocarb_III-Berner.pdf .

The conclusion from all this is that carbon dioxide change does not cause significant climate change. Actions based on the human-caused global warming mistake put freedom and prosperity at risk.

As I have noted before, it is of interest to me how quickly people with no scientific qualifications have suddenly become experts on climate science and interpreting data. The field is exquisitely complex, and to suppose that any one of us can pull data off of the internet, crunch the numbers and come up with a valid hypothesis that negates all of the original research and peer-reviewed analysis carried out by real climate scientists is staggeringly arrogant.

But please, Mr Pangburn – submit your interpretation for peer-review (and I mean by climate scientists, not by economists, art historians or civil engineers). If it stands up to scrutiny, I am sure that Nature Geoscience will be glad to print it for further consideration by the scientific community.

Fern Mackenzie

Dan Pangburn said: “For most of the history of earth carbon dioxide level has been several times higher than it is at the present as shown at http://www.geocraft.com/WVFossils/Reference_Docs/Geocarb_III-Berner.pdf .

The conclusion from all this is that carbon dioxide change does not cause significant climate change. Actions based on the human-caused global warming mistake put freedom and prosperity at risk”.

During the Jurassic and Cretaceous periods carbon dioxide concentrations were several times higher than they are now. Temperatures were also much higher. The world was very tropical and the forests and estuarine environments were very high in plant and algal life. This dead biomass, over time, became submerged by sediments and was eventually transformed into coal and oil and gas. At the same time, this depleted the atmosphere of carbon dioxide and temperatures dropped. This process took millions of years. Now we are bringing that buried biomass to the surface and burning it and turning it into carbon dioxide again in a reversal of what happened 50 to 60 million years ago.. The temperature is rising, surprise surprise.

The only problem is we are doing (changing carbon dioxide concentrations) in a matter of centuries what originally took millions of years. No wonder the climate is in serious trouble, it is not the absolute change which is bad, it is the rate of change.

Ian Forrester

Excellent posts.
For a very funny take on this rate of change issue, check out http://bigcitylib.blogspot.com/search/label/Global%20Warming
(Thursday, January 10, 2008: Tim Ball Denies Darwin!). The original article is hysterical, with Tim & Tom (Dumb & Dumber) taking on geological time, God and environmental “extremists”. See the whole awful thing at http://canadafreepress.com/index.php/article/1272.

Fern Mackenzie

Fern, thanks for the kind words. I had checked BCL’s post but hadn’t read the CFP article itself until you jogged my memory.

It is full of inaccuracies (what else can you expect from the Tim and Tom show). They completely mis-characterized Darwin’s religious beliefs. He was far removed from the atheist that they portray. He had a strong religious and Christian faith with which he gradually became disenchanted because of his scientific findings. However, he did believe in creation, that is the creation of the original life form since he was unaware of any explanation for abiogenesis. Towards the end of his life he became an agnostic (in its true meaning of “I don’t know”) but atheism was never an option for him.

Just goes to show how poorly informed on everything these two are.

Bear with me and I will quote two very relevant statements from Darwin’s writings.

“I cannot pretend to throw the least light on such abstruse problems. The mystery of the beginning of all things is insoluble to us; and I for one must be content to remain an Agnostic”. Taken from his autobiography (http://www.update.uu.se/~fbendz/library/cd_relig.htm)

“….we must likewise admit that all the organic beings which have ever lived on this earth may be descended from some one primordial form.” From “On the Origin of Species”.

Ian Forrester

One of the most misunderstood concepts in science is Darwin’s “survival of the fittest” – which most people interpret as “survival of the strongest” or “… most powerful.” The notion that something small & relatively weak might be better suited to the environment than a muscle-bound homo sapien is usually lost on them!

As for his faith, I wouldn’t expect anything else from these fellows. I am surprised, though, that they would strike out in this direction given that it is likely to do their credibility no good at all, and lately they could really use an infusion.

Fern Mackenzie

A useful graph of carbon dioxide level and global temperature over geologic time (CO2 from Berner and temperature from Scotese http://www.scotese.com/climate.htm) is shown at http://mysite.verizon.net/mhieb/WVFossils/Carboniferous_climate.html. This shows that carbon dioxide level does not influence average global temperature. Especially note the temperature dip at the end of the Jurassic while CO2 was about 5 times the present level and the steadily declining CO2 level and fairly constant temperature during the Cretacious.

http://epw.senate.gov/public/index.cfm?FuseAction=Minority.SenateReport lists 4000 scientists and engineers who conclude that the climate is normal. Anybody who actually looks at historical climate data will be forced to the same conclusion.

400 not 4000, and questionable how many are scientists and if any of them are prominent. It has been debunked many times, including here:

http://www.desmogblog.com/
{cut here} 400-prominent-scientists-dispute-global-warming-bunk

Dan Pangburn said: “This shows that carbon dioxide level does not influence average global temperature”.

Unfortunately for him if you actually read one of Berner’s papers (the CO2 data which are shown in DP’s link were supposedly taken from one of his 2001 papers) you will find that it does not look anything like what is presented in his 2001 paper. In particular, there is no lowering of CO2 concentration at 150mya BP. I don’t know which 2001 paper is referred to in the link but I did find this 2001 paper:

http://www.geocraft.com/WVFossils/Reference_Docs/Geocarb_III-Berner.pdf

Here is a quote from that paper: “Nevertheless, the overall trend remains. This means that over the long term there is indeed a correlation between CO2 and paleotemperature, as manifested by the atmospheric greenhouse effect”.

Mmmm who should we believe? An expert or someone who trawls right wing web sites so he can cherry pick data and doesn’t bother to check its authenticity?

Ian Forrester

Some people may actually compare the link you give to the one I gave and discover that they are the same. The results of his study are summarized in Figure 13 of that paper. The results speak for themselves.
I doubt that the folks at CDIAC and NCDC would take kindly to their sites being referred to as right wing web sites.

If you check out this link

http://mysite.verizon.net/mhieb/WVFossils/Carboniferous_climate.htm

which you provided, you will see that it does not agree with accepted temperature profiles

(http://www.palaeos.com/Mesozoic/Mesozoic.htm#Climate).

In particular, there is no documentation to support the cooling shown between the Jurassic and Cretaceous.

Who drew that erroneous curve? And if you posted the same link to Berner’s paper as I did, did you actually read it? I very much doubt it since you would have not made your erroneous statement about carbon dioxide levels and temperature. Your conclusion is completely opposite to what Berner says and what the data show.

As I have said to many people before, read the actual papers, do not believe the misquotes, cherry picking and mis-representations you find on your favourite right wing web sites.

When did I ever refer to CDIAC and NCDC as right wing web sites? Get a grip on reality, you are completely misinterpreting their data or are guilty of mis-representing what you found on these sites.

Ian Forrester

I find the characterization of people and websites as right and left wing to be polarizing, and although some folks might self-identify as belonging to either philosophically incoherrent “wing”, I wonder if (nay, hope!) a plea to folks to avoid puking partisan junk on every thread would be more constructive.

Steve, you may not like the term “right wing sites” but unfortunately they are well entrenched.

For example go to:

http://www.therightwing.com/

This is a modified Google Search site that claims: “The Right Wing Search allows you to search the best resources on the Right. You will get results from only right wing sites”.

Thus it is very easy for people to only get results which confirm their own biases. I think that these biased sites should be called as such (if a left wing site is as guilty of misinformation it should be called too). I believe in calling a spade a spade.

To me the polarization is between truth and dishonesty but it is much harder to convince people that they are viewing dishonest material whereas they seem to accept being called right wing, in fact some people seem to think of it as a badge of honour.

Ian Forrester

It’s good to know who and what you have in mind when you use that phrase. I myself visit many websites that are certainly not left-wing, so I appreciate this clarification.

Look back at my post. All of the sites that were referenced are either CDIAC or NCDC except for the Berner link which you also used.

The ‘erroneous curve’ came from

http://www.scotese.com/climate.htm

as also noted earlier. Is Scotese wrong? Hieb’s graph is just a convienient superposition of the work of Brenner and Scotese but anyone can make their own or check his.

Uh, err, which anti-science website did I quote from Ian?

This is a new study, so some caution is in order. The consensus among scientists is that the Antarctic is gaining mass.

=“It reinforces the finding that the Antarctic is losing mass — which is still not a well-accepted result,”=
- Eric Rignot

Agreed. Most other studies of the Antarctic don’t jibe with Rignot’s results.

Secondly, snowfall in the interior was not actually measured; climate models were used to predict what it might be.

But I can tell from your posts that you spend way too much time on that type of web site. Try reading the scientific literature or at least find some sites which will keep you up to date on what is new and not the old stuff you keep reciting.

It is very funny when you see all the deniers quoting the same out of date paper all at the same time when it gets reported on one of their favourite web sites.

Ian Forrester

Still a mind reader, eh Ian?

Your posts reflect the AGW denier talking points. Do they send you people e-mail alerts and urge you to all descend on some particular blog and saturate it with your phony research? It is so predictable that it makes a laughing stock out of all you deniers, you are so flock-like and predictable.

Ian Forrester

Just trying to get a handle on the Antarctic and whether it is losing ice mass or not. What does the concensus say Ian?

there has been no consensus, and the IPCC reports specifically address the previous lack of comprehensive or reliable data respecting the Antarctica ice sheet. Previous papers on the subject have been “all over the map”. That is why this report is so important. It is the first analysis of the situation that uses the most precise data available, and deals with the entire continent. It provides a new baseline for discussion and further research, from which will derive a consensus. Ongoing research will help refine, correct, challenge, confirm etc etc the findings of Rignot et al, but for the moment it is worth paying attention to the point: a major study using the most current methods and data has suggested that the problem might be worse than we thought.

Fern Mackenzie

It is stunning to see that this website continues to have it’s discussions ruined by a few rogue posters who manage to script dissent on the first reply to every story. From there, the discussion becomes about that dissent rather than a discussion of what really matters.
Melting of both polar regions [n and s] is beyond worst predictions and global dimming is actually hiding much worse effects of CO2 emissions. Therefore, we are really in trouble within 20 years, and the urgency for remedial action is greater than we thought. Instead of recognizing that urgency, we get stuck on silly distractions like “ya but the total mass of ice is greater”.

——————————————————-
GLOBAL WARMING? IT’S THE COLDEST WINTER IN DECADES
——————————————————-

By Tony Bonnici
Daily Express [London]
Monday February 18,2008

NEW evidence has cast doubt on claims that the world’s ice-caps are melting, it emerged last night.
Satellite data shows that concerns over the levels of sea ice may have been premature.

It was feared that the polar caps were vanishing because of the effects of global warming.

But figures from the respected US National Oceanic and Atmospheric Administration show that almost all the “lost” ice has come back.

Ice levels which had shrunk from 13million sq km in January 2007 to just four million in October, are almost back to their original levels.

Figures show that there is nearly a third more ice in Antarctica than is usual for the time of year.

The data flies in the face of many current thinkers and will be seized on by climate change sceptics who deny that the world is undergoing global warming.

A photograph of polar bears clinging on to a melting iceberg has become one of the most enduring images in the campaign against climate change.

It was used by former US Vice President Al Gore during his Inconvenient Truth lectures about mankind’s impact on the world. But scientists say the northern hemisphere has endured its coldest winter in decades.

They add that snow cover across the area is at its greatest since 1966.

The one exception is Western Europe, which has - until the weekend when temperatures plunged to as low as -10C in some places - been basking in unseasonably warm weather. The UK has reported one of its warmest winters on record.

However, vast swathes of the world have suffered chaos because of some of the heaviest snowfalls in decades.

Central and southern China, the USA and Canada were hit hard by snowstorms.

Even the Middle East saw snow, with Jerusalem, Damascus, Amman and northern Saudi Arabia reporting the heaviest falls in years and below-zero temperatures. Meanwhile, in Afghanistan snow and freezing weather killed 120 people.

In Britain the barmy February weather came to an abrupt halt at the weekend as temperatures plunged to -10C in central England.

Experts believe that this month could end up as one of the coldest Februaries in Britain in the past 10 years.

The freezing night-time conditions look set to stay around -8C until at least the middle of the week.

A Met Office spokesman explained: “There has been little or no cloud cover across England and Wales. So there is a capacity for a fair bit of heat to be able to escape at night.

“It has been warmer in Scotland but that’s because it has been cloudy there.

“Until the weekend the temperatures were in the 14s and 15s, and we will see a return to that later this week, though it will look grey and overcast when the clouds return.”

But he added that there was little chance of snow. He said: “When the rain comes it will get warmer.”

——————————————————

Http://www.express.co.uk/posts/view/35266/Global-warming-It-s-the-coldest-winter-in-decades (accessed 19 Feb. 2008).

Excellent post Andy! It’s amazing how actual evidence shuts up all the sheep pretty quickly. It’s almost like they ignore it and move on to some other article somewhere else. I prefer real modern evidence over some broken computer model that was built in the 70’s, that if you follow from then until now, is already proven wrong! You have over 30 years of actual data to compare it against, and it is dead wrong. So I don’t know why people continue to cling to the IPCC BS. I am beginning to believe more and more that there is more to this then meets the eye. The United Nations may be using this to suck money out of industrialized nations and funnel it to poorer nations through the trading of carbon credits. You take from the rich and give to the poor. They are the modern day Robin hood! Cheers.

I am interested in knowing if anyone has ever considered geothermal heat as a cause of melting ice sheets. This makes much more sense, to me, than a 1 degree change in the atmosphere. For instance, if the average temperature is a -20 degrees in a polar region how could ice melt so dramatically if the average temperature rises to -19 degrees?

In our northern communities (U.S.) many homes and businesses have electrical wires in the driveways and walkways that warms the ground to melt ice. Warming the ground in this manner quickly removes the ice and snow.

Geothermal activity would explain the spotty and unexplainable melting of glaciers in some regions and not others.

Science should be science and not a political football. I want the air to be clean and breathable as much as anyone. I appreciate the work that has been accomplished in the last 30 years. But I don’t appreciate that true science has been seemingly high-jacked for personal gain or to advance a particular agenda.

I truly would like to hear of research that has exhausted every possibility of geothermal activity being a source that is contributing to melting ice and changing habitats.

Why would you think geothermal heat is responsible for the warming over the past century? What has changed under the earth, if anything?

The greenhouse effect is an explanation that takes recent history into account; that the warming over the past century is due mainly to greenhouse gases produced by humans with industry, cars, planes etc.

Quickly, a 1 degree rise in the average temperature globally does not reflect a 1 degree rise in the average temp in either the arctic or antarctic. those areas are showing much higher temperatures than historically seen.
while there may be some incidents of localized geo-warming (as possible in some Antarctic areas) glaciers are melting almost everywhere and in regions with virtually no such warming apparent.

Just follow the money and you’ll have your answer. No money to be made from “the earth is just going round as usual” now is there? Plenty to be made from “green this, green that” “more taxes” “more donations to save the planet”….right?

Without a doubt we are polluting our oceans, rivers and lakes. We are cutting down too many trees. We are polluting our cities with the sheer numbers of automobiles….but cities in Europe have been in that boat for a long long time.

Our bodies (lungs mainly)will suffer the consequences, but do we see better healthcare as a goal to have a World Conference on especially since most of the damage has already been done to our children. Do we see Millions being spend on improving their upcoming life…NO SAVING THE PLANET is not a Goal that’s achievable at all.

A fortune will go into the pockets of politicians and media hype and keep them and their useless organizations living high on the hog.

Obviously the fear factor is alive and well in Global Warming……promote it and watch the money roll in.

In the post Ice Caps Growing cheering & sneering breakout as the poster ‘proves’ AGW has been stopped & that last year’s icy winter brought back the arctic ice to an even greater extent after the record 2007 Arctic ice extent minimum. Yes, indeedy, as of March 2008, the Arctic maximum ice extent was 500,000 square kilometers GREATER than the March 2007 maximum ice extent.

But far from proving AGW ISN’T, mid-June 2008 shows the Arctic ice extent advantage of 500,000 square kilometers of ice that was worth cheering is….0 square kilometers greater now than the mid-June 2007 ice extent.

Actually, the 2008 Arctic maximum ice extent never was too worthy of cheering, since much of it was thin 1 year ice that recovered during the cold winter, but was not multi-year thick ice based on many years of cold.

I say its extremely worrying and that we lazy humans should get off our big bums and start working. We’ve been allowing this to happen for too long and if we don’t do anything we’ll all die. The whole human generation, gone. Forever. I say the Ice Age will wipe half of us out and the green house effect will take care of the rest.

[x]

In less than a decade, climate change-induced sea level rise could force thousands of people to migrate from some small island developing states (SIDS), according to the executive director of the United Nations Environment Program.

The world’s 52 small island developing states (SIDS) increasingly share sea level rise and other escalating environmental threats that are further aggravated by economic insecurities, Achim Steiner added.

What makes this situation even more grievous is that the climate...

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