A landmark study refines measurements of losses in Greenland and Antarctica and how ice melt is contributing to rising seas. Here's why that is important.
By Rebecca Boyle Posted 11.29.2012 at 3:00 pm 24 Comments

Calved Iceberg
Calved Iceberg An iceberg in or just outside the Ilulissat fjord that likely calved from Jakobshavn Isbrae, the fastest glacier in west Greenland. It is rumored that it was an iceberg from this glacier that sank the Titanic. Courtesy of Ian Joughin
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Click to launch a stunning photo gallery of melting ice in Greenland and Antarctica

All of the ice sheets in the world except one are losing prodigious mass, according to a landmark new survey of satellite data. Greenland and Antarctica are now losing more than three times as much ice as they were in the 1990s. Greenland alone is shedding more ice-mass today than it was in 1992 by a factor of five. And since 1992, ice loss from the Greenland and Antarctic ice sheets has contributed to an 11-millimeter rise in sea levels, the new study says.

“As the climate warms, we’re going to lose more mass and the losses will be higher by the end of the century,” said Ian Joughin, senior principal scientist at the Polar Science Center Applied Physics Lab at the University of Washington and a co-author. “From any 20-year record, and this 20-year record in particular, we just can’t at this point extrapolate. But we can see that the trend is towards increases, and that that’s something we do need to worry about.”

These cold numbers are the clearest evidence yet of Earth’s warming polar regions, more than twice as accurate as the numbers in the Nobel Peace Prize-winning 2007 IPCC climate report. To come up with these statistics, 47 scientists from 26 institutions used 50 combined years of data from 10 different satellites.

Why is this important?

Previous estimates of ice-sheet loss have been shaky at best, with widespread variation in different studies of Greenland and Antarctica since 1998. These disparate estimates make it difficult to nail down solid data for climate models--it’s not clear how much ice is being lost, and just when and where. Some studies have even suggested certain areas are gaining ice, creating uncertainty about Earth’s ice “mass balance.” This was especially true in Antarctica.

“While most studies agree that ice sheets are losing mass in most places and in aggregate, the precise rate has been much more difficult to determine,” explained Jesse Smith, senior editor of the journal Science, which publishes the paper today. “That’s where this study makes its mark.”

The research team, led by University of Leeds professor Andrew Shepherd, combined several types of data sets and methods and re-processed the records, ensuring they were comparing apples to apples. No one had ever done this before; previously, scientists using each ice-measurement method released independent estimates for different locations.

What did they do?

Measuring ice loss happens in a number of ways. Satellite laser and radar instruments measure the height of ice caps, and other instruments can measure the gravitational influence of ice sheets. This is a supremely complicated measurement involving an accounting of Earth’s mantle and how the ice weighs it down.

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Science, Rebecca Boyle, climate change, glacial speed, glaciers, global warming, melting ice caps, polar ice caps, rising sea levels
Global positioning satellites assisted here, by detecting just one millimeter per year of motion. This dramatically refined the gravity effect of ice in Antarctica, in particular. Scientists even used nuclear physics to examine changes inside rocks in Antarctica, which can tell how long the rocks were exposed to the sun as opposed to buried in ice.

The study correlated data from the same places and times, and discarded some outlying observations that couldn’t be cross-checked. The refined and combined measurements are clearer than ever, and show that most of Antarctica--not to mention Greenland--is indeed losing ice. The authors say East Antarctica is gaining some ice, but not nearly enough to compensate for losses in West Antarctica and the Antarctic peninsula.

The study shows the importance of a reliable satellite network, many scientists said. Without cross-calibrated observational tools, this type of measurement would be much more difficult--and many of the planet’s eyes in the sky, including satellites owned by NASA and ESA, are aging and even failing.

“We need to not just make snapshots, but we need to make sustained measurements, preferably through a coordinated international effort,” Joughin said.

What does it mean?

Better data will be used to make better models of future climate, allowing scientists to more accurately predict how polar ice may continue to melt. Shepherd said he hoped United Nations members meeting in Doha, Qatar this week would take the study to heart. He also said he hoped climate scientists would start incorporating the new data into their models as soon as possible--it's available today.

"We would hope that people would adopt this as the universal record," he said.

But the physics of glaciers, waves, sea circulation and other variables are still not well understood, Joughin pointed out. Climate scientists still want more and better data on these phenomena, as well as the ice sheets, to improve their models. “Just as economists can say that the stock market will likely be higher in 2100, they can’t say exactly how high or at what rate, and they can’t really just take any 20-year period and extrapolate that and expect to get the right answer,” Joughin said. “That’s really what’s going on [here]." Still, it’s safe to say we now have clear evidence the seas are rising.

24 Comments

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Robot
11/29/12 at 3:13 pm

As planet x approaches with December 21st 2012, the planets extra gravitational pull is causing an excessive amount of solar flares, thereby causing global warming giving President Obamas the election to which we all die after the fiscal cliff.

The good news is in 4 years President Obama will be gone, we hit bottom on the fiscal cliff and planet x will be heading out into the cosmos and our Earth will enter and ice age.

Now everyone, clap your hands and say YEA!!!!!

……………………………………………

Or as I believe the sun cycles causing global warming and as the science community redundantly confirms over and over again, humans are accelerating the process, with the USA and the rest of the world at a fiscal financial budget cliff doom, so we must continue burning our fossil fuels as fast as we can to keep those economies up and support the ever growing 7 billion plus people on planet Earth.

Eventually with CO2, pollution, population growth and reduces Earth resources, something will and must crash to with the world’s population will fall to 1% and we will start again, after much suffering.

………………………………………….

Some crap is coming. We cannot stop it and I have no idea what to do anyways.

The end.

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CER1701
11/29/12 at 3:23 pm

Yeah, Yeah, I know this is all man's fault and we are all supposed to give up our money, rights, freedoms, and way of life to stop it. But has anyone ever correlated the data of Earth's magnetic field fluctuations and the approaching solar maximum, with Earth's apparent global warming trends?

I'm just another guy who's too busy learning your laws, to have time to obey them!

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Robot
11/29/12 at 3:44 pm

By the way, had Mitt Romney made president, my above comment would stay the same. The effect of who was elected really has no effect.

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misthiocracy
11/29/12 at 4:14 pm

A 1.1 centimeter rise in sea levels since 1992.

That's 0.055 centimeters per year.

At that rate, sea levels will rise by 5.5 centimeters by 2112.

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BruceVoigt
11/29/12 at 4:14 pm

Ice packs around the world (perma frost) have received jolts of radiation causing internal rot (melting)! Cold of winter does not penetrate this ice.

Yelowknife NWT six day trend -34 -33 -33 -35 -23 -31

Perma frost will recover, Alaska's Columbia glacier ia doomed

I have food stored along the Beaufort Sea in a covered seven foot hole dug into the permafrost. Through the years of adding food I found things frozen solid.

I have discovered that this phenomenon is speratic, thinking that if this area was involved that it would be still cold enough not to rot and refreeze. Hoping I never have to find out.
World Peace Guys

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Robot
11/29/12 at 4:21 pm

Hey!!!!
Those are my lotto numbers " -34 -33 -33 -35 -23 -31 "!!!
Were you behind me at the gas station last night?

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dkella
11/29/12 at 4:43 pm

might get colder next year, could be the end of the warming trend. Might be a good thing to be burning all those fossil fuels. Less of an ice age.

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joerayhays
11/29/12 at 5:02 pm

Misthiocracy, you're assuming the rate is linear.

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syfyguy
11/29/12 at 5:30 pm

@CER1701 - Actually, there have been many, many studies on whether fluctuations in the magnetic field and the solar maximum contribute to climate change. The results have overwhelmingly been: not much. Oh, there were two Danish scientists who claim to have discovered these factors are contributing more to climate change than humanity, but typical for anti-climate change science, their findings cannot be reproduced by anyone, and they are being laughed out of the scientific community.

Unfortunately, we are seeing a very dangerous trend in science. Anti-climate change scientists and creation scientists are falsifying results at an alarming rate. For the scientific community, this is not such a big deal, as their ridiculous claims are proven wrong by even the simplest of science. By then though, the damage has been done. The conservative right loves to jump on any pseudo-science claim that supports their belief, regardless of credibility. They then make this false claim over and over to the masses until people believe them. People desperately NEED to believe them. This makes it hard for real science to happen, and it is destroying America's scholarly status in the world.

We are falling far behind the rest of the world in many sciences, such as genetics. Genetics relies heavily on evolution. Thanks to the lying right and religious fanatics, only 40% of Americans believe in and understand evolution. A large percentage of the country believes the Earth is only 6,000 years old, and that dinosaurs coexisted with man. They would have us believe that there is this great conspiracy involving 95% of all scientists. It is no wonder that a country that consistently denies science is falling behind the rest.

This is not the first time in our history religion and belief have denied science. We now have a choice: to continue to advance our civilization through science and technology, or we can go backwards to the dark age way of thinking where religion and belief ruled the land, just as humanity did after the Roman Empire.

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11/29/12 at 7:56 pm

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gizmowiz
11/30/12 at 3:05 am

What we do know is that life goes on--regardless of the changes mankind is bringing about life will evolve with the changes. Get used to it. Change is natural. Life is change. Besides that it's more interesting seeing the changes occur in human lifetimes instead of millions of years. All those who bemoan the changes are those living on the coastlines and for those I say suck it up.

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matsci1
11/30/12 at 7:07 am

Yet another study that indicates that the climate is warming up and that, if it continues, there will be consequences. This will probably get the standard treatment… just file it in the “Doom and Gloom” drawer with the others and keep on partying.

I mean, what do scientists know about how environmental policy should be carried out compared to the politicians? The problem, in the eyes of the politicians, is that the scientists keep trying to confuse the issue with facts. Even the common man on the street can tell that things are as they should be …winter: cold…summer: hot… right?

Given the behavior of the of the politicians and the masses to this and other problems that are confronting the world today, the wisest course of action seems to be (for the ones that actually recognize that there is a problem) to prepare themselves and there families so that when the situation has reached a point where the infrastructure is effected they still have access to the basic necessities.

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Bagpipes100
11/30/12 at 7:52 am

This ice has all melted before and will freeze back over again, and then melt again. Just look at the history books people. Quit being a bunch of chicken littles.

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Robot
11/30/12 at 8:55 am

With the USA being economically defunk, 16 billion in debt and the fiscal cliff just looming weeks away, which will cause an depression and or if the government does makes budget will still cause a depression, they are desperate for an economic stimulus.

I want with all the articles that argue man made global warming is really just a means to ignore the problem temporarily and for the USA to hurry up and burn more coal and find more shell oil, which has been announced ALOT in the media!

So for the benefit of economic bliss, the government is tactfully promoting arguments to manmade global warming, so they can be free to have an economic upswing with coal and oil.

Of course, this will just make matters worse in the long run, but those politicians in office will preserve their careers and be happy.

Politically, it is short term advantageous to ignore the mad made global warming problem for the USA economy and the politicians.

Of course, the weather isn't going to go away.....

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cubicle
11/30/12 at 9:29 am

Here we go again, the world is ending! I love it! I am not doubting the earth is warming but "Previous estimates of ice-sheet loss have been shaky at best" come on! So what they are saying is up to this point we have been guessing about the loss of ice, but NOW we are REALLY sure. Yeah until the next new satellite comes out. Give me a break.

Scare tactics, all of it. Pathetic.

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Robot
11/30/12 at 11:19 am

cubicle,
No no no, it not ending. The Earth is just turning is not a slushy.

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rlb2
11/30/12 at 2:13 pm

Another frightening thing to think about is if all the glaciers and ice is melting at an accelerating rate in the northern hemisphere where the Antarctica's is said to be gaining mass then maybe sooner than we think the earth is in for a sudden rotational fix.

Antarctica is nearly twice the size of Australia. At a number of points in its long history it was farther north, experienced a tropical or temperate climate, was covered in forests, and inhabited by various ancient life-forms. Think about it, a rotating object who center of gravity changes wobbles more. In this case the mass changes from a solid fixed area to a fluid motion moving an immense amount of mass to a different location on earth. Just 25 million years ago the Antarctica was in a much warmer place than it is today maybe it will be again real soon.

Ha, maybe global warming will cause the earth to wobble violently on Dec 21 2012..

Ron Bennett

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Robot
11/30/12 at 2:24 pm

rlb2,
I have my order in for the new Mayan calendar coming out 22nd December 2012. Optimistically, those Mayan calendars are 5126 years long. You know for a society to plan for a future that long, good things must come! ;)

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riff_raff
11/30/12 at 11:40 pm

During the past couple decades, the Antarctic continent's ice coverage has been increasing gradually. And much of the globe's ice mass is contained in the Antarctic.

http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seaice.anomaly.antarctic.png

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rlb2
12/02/12 at 12:51 am

Robot It's funny how accurate the famers almanac use to be to predict a small time into the future. It really isn't that difficult to predict the future. For me if my wife yells at me I know it's time to take out the garbage if my mother in law yells at me I know there is going to be storm coming.

Ron Bennett

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Mark Ofthebeast
12/02/12 at 1:37 am

"A 1.1 centimeter rise in sea levels since 1992.
That's 0.055 centimeters per year.
At that rate, sea levels will rise by 5.5 centimeters by 2112."- misthiocracy

Obviously we are all doomed. Unless we can swim. Or control water the way the Dutch can.

On the brighter side, some of us can still do math...

Seriously, the poles are notoriously dry- it might be worth considering if the decline is due to reduced precipitation("snow" for you laypeople) to some degree.

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Robot
12/02/12 at 8:51 am

I hope everyone pause to look at the pictures in this article of Greenland And Antarctica. Well done and kudos to the photographer. I was I was with him or her as there assistant!

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Peter10
12/02/12 at 2:40 pm

Well, I live in Mexico City at 2,240 meters (7,350 feet for Americans) altitude, so I don't expect to get my feet wet. Now you, living on the US' East and West coasts, please stay where you are. We too don't want any illegal US immigrants here.

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bosox750
12/12/12 at 5:34 pm

Funny how alot of these people who dont believe in climate change,are out collecting guns,ammo,food,water,ect.for there end of the world bunkers.
I wish the media,politicions,ect. would stop using the title "global warming",and use climate change,and or enviromental change.Im tired of hereing arguements like,we had record snowfall,cold temp.,or "well it still gets hot in summer,and cold in winter"as if thats proof its not happening.The fact is the climate is changing.If man is causing it to speed up,or not.The point is it IS HAPPENING!The earth has always gone through major changes and what are we going to do to deal with it.Unfortunatly man has become so used to manipulating our environment to fit our needs,we have know idea what to do when se cant.We would rather argue about semantics.We do affect our environment all the time pollution,clear cutting,development of highways,damns,nuclear testing,genetic manipulation,industry's use of recources,large scale mining or fraking,even basic farming diverts water from rivers for crops wich inturn changes everything down river that depends on that water.Im not saying all of this is bad.It is what it is.
The fact that we affect our surroundings so much,and that this has no affect on our over all climate is like saying the food you eat has nothing to do with your over all health.It can affect your energy which affects weight,cholesteral,knee hip pain,heart disease,stroke,cancer,and other diseas's.Some of which may be genetic and happen know matter what we do,but we still do what our Dr.s say and make changes that can influence the over all outcome.We dont argue and say i never died from anything before so why should i change what i eat.
As long as you give people an excuse to deny the problem exists like calling global WARMING these nay sayers will continue to spue BS,because they know alot of people have know idea what the process is.It doesnt mean it is just going to keep getting hotter every day till we all melt.Even though the actually outcome is not that much differant.


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