National Geographic News
The calving front of Thwaites Ice Shelf looking at the ice below the water's surface as seen from the NASA DC-8 on Oct. 16, 2012. Note how the water acts as a blue filter.

The calving front of the Thwaites ice shelf in Antarctica is seen on October 16, 2012. The melting shelf is causing the glacier behind it to collapse, a new study suggests.

PHOTOGRAPH BY JAMES YUNGEL, NASA

Brian Clark Howard

National Geographic

Published May 12, 2014

A massive glacier system in West Antarctica has started collapsing because of global warming and will contribute to significant worldwide sea-level rise, two teams of scientists warn in a pair of major studies released Monday.

Scientists had previously thought the two-mile-thick (3.2 kilometers) glacier system would remain stable for thousands of years, but new research suggests a faster time frame for melting.

A rapidly melting section of the West Antarctic Ice Sheet appears to be in irreversible decline and will sink into the sea, scientists at the University of California, Irvine and NASA reported Monday.

"This retreat will have major implications for sea-level rise worldwide," said Eric Rignot, a UC-Irvine Earth science professor and lead author of a study to be published in a journal of the American Geophysical Union.

A map of the Antarctic ice.

The study presents evidence, based on 40 years of observations, that six big glaciers in the Amundsen Sea "have passed the point of no return," Rignot said on a Monday conference call with reporters.

The glaciers contain enough ice to raise global sea level by 4 feet (1.2 meters) and are melting faster than most scientists had expected, which will require adjusting estimates of sea-level rise, said Rignot, who is also a glaciologist at NASA's Jet Propulsion Laboratory in Pasadena, California.

At their current rates of melting, he said, these glaciers would disappear in about two centuries, though "it could proceed faster or slower."

More advanced computer modeling will be needed to estimate the rates, he said.

A photo of crevasses in Thwaites glacier in West Antarctica.
Crevasses are seen in the Thwaites glacier on October 16, 2012.
PHOTOGRAPH BY JAMES YUNGEL, NASA

Computer Modeling Reveals Surprises

Some of that modeling is already under way and forms the basis for another study on West Antarctic ice melt released on Monday, which finds that a major glacial system in the region that was previously thought stable is collapsing.

Ian Joughin, who studies the physics of glaciers at the University of Washington, Seattle, says that the Thwaites glacier on Antarctica's Amundsen Sea was thought to be "stabilized for a few thousand years."

But "what we have shown is this glacier is really in the early stages of collapse," says Joughin, lead author of a study published separately in the journal Science on Monday.

If the whole glacier system melts, Joughin says, it would raise global sea levels about 24 inches (60 centimeters), he adds. The process will take a while, roughly 200 to 900 years, Joughin and colleagues estimate, depending on how fast temperatures rise and how much snow falls in the area.

Richard Alley, a professor of Earth sciences at Penn State University in State College, Pennsylvania, who was not involved in either research project, says both are important. The data from Rignot's group is consistent with the computer modeling by Joughin's group, he says.

Next, the work of both teams needs to be confirmed by other models, he adds.

"But these results are sobering," he says, "even the possibility that we have already committed to three-plus meters of sea-level rise from West Antarctica will be disquieting to many people, even if the rise waits centuries before arriving."

Alley adds that the scientists avoided simulating "a worst-case scenario" of loss of all ice from Antarctica.

A photo of icebergs in Pine Island Bay off Thwaites glacier in West Antarctica.
Icebergs that appear to have broken off Thwaites glacier spread across Pine Island Bay.
PHOTOGRAPH BY NASA

Unstable Ice

Rignot says that once the six glaciers near the coast melt, it is possible that the rest of the ice in West Antarctica could eventually follow. As a result of this new evidence published in Geophysical Research Letters, forecasts for global sea-level rise will likely need to be adjusted.

Joughin says that the collapse of the Thwaites glacier in particular could endanger much of the rest of the huge West Antarctic Ice Sheet, since the systems are connected.

"Imagine trying to take out part of a building and expecting the other half to keep on standing," he says.

If the entire West Antarctic Ice Sheet did melt, sea level would rise 11 feet (3.3 meters), according to previous research. (See "Rising Seas" in National Geographic magazine.)

Joughin says the breakup of the Thwaites glacier will resemble mechanical failure more than straight-up melting.

The ice will slide into the ocean, where it will break off and float away, adding to the volume of water in the sea.

A mixture of rock and frozen water has been holding the glacier back. Contrary to recent thinking, however, the glacier is no longer being held in place, Joughin says.

The ice shelf that has extended out over the ocean is melting, thanks to warmer temperatures, and that has decreased the friction that has held the glacier behind it in place. As pieces of the shelf break off, more of the ice behind it slides forward.

"It's a little like how you get more flow out of a thicker hose than a thinner hose," says Joughin, referring to an acceleration of the glacier sliding into the ocean.

Scientists had previously thought that a sill of bedrock, a vertical rock formation under the ocean, was holding back the advance of the glacier like a dam. But the work of Joughin and team suggests melting has greased the way over the rock.

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125 comments
Gerrit Bogaers
Gerrit Bogaers

I have been member of a small paragnost Workgroup as off 1983 till 2005, of which since 1993 till 2005 as notulist.  On Saturday 13 April 1996 Cees de Haar, medium,  Alphen aan den Rijn, Netherlands, got the following message, reading in its English translation, (quotation:)  "(..) The climate is not going well. The world's tectonic plates are scrolling into each other in the sliding process. In Japan, the tectonic plates slide over each other. There are large landslides and earthquakes. In the Philippines, extinct volcanoes will start working again as if they light each other as if in a chain of fire. This creates soot and dust emissions. The effect is similar to what happened when Saddam Hussein put his oil wells on fire. It is getting warmer. Because of this temperature rise and the behavior of the earth crust, this results in the Antarctic ice shift. This will not be noticed this year, it goes very slowly, but next year it will stand out. The governments of all countries will try the shifting to stop, but it is a plate the size of France with a thickness of two to three kilometers. The shift is not to stop."

On a next occasion (28 September 1996) the group received the messages in broken Dutch, (tranlated in the same style into broken English:)  "But I can announce to you that the ice cap   will break apart.   The large crack will form, but this goes quicker than any government dares to think, beacuse they are talking about now and ten thousand years, but it will definitely happen in your life. Then the consequences are incalculable, because I can announce to you, even we ourselves cannot see what is going to happen. It's well established for us what so all can happen, but not all, because a very large tidal wave is coming, or rather a displacement of water, of which we also cannot completely see what he is going to drag out, but this is decisively on a decade at most to happen. Then you go in this era, that almost seven years will last. This then goes under a huge debt burden, which all governments will have, which would then still remain. Because there will be much wiped going to be, but also new land will come forward, and this is nice, but there are also other messages come through, becaus it's also true that new land is raised, but the old land with its pollution will move towards America. Moreover the new icecap will be formed there.  I can announce to you that the crack, which walks into the ice, is momentarily being developed under the ice. It's already there in the form of haircuts, but they gorge, and they are there. The authorities give it attention, but they rather like to put their heads in the sand, so they almost look no further. This is going to change, beacuse within three years they will also have to come to the conclusion that the cracks will grow bigger. Then this giant pack of ice will begin to set in motion and it can certainly not be stopped. All the governmens of the major nations will be present to see what can be done about it, but no one knows, because the suggestions are made for throwing big bombs on it, but science warns that larger implications are then being set into motion, because the ice shelf can go off with a quantity which is incalculable.  Bit it is going to happen within that year, which we will now enumerate, but again is is very difficult for us to work with your timetable, but as a matter of speech it around 2004 the era begins that the great mass of ice is going to put in motion, and this mass is definitely the size of the whole of France and the thickness of about two to three kilometers thick. This is going to be put in motion. But we have for you at least the good news that your country and other parts of Germany and the North Sea, which is often reported, will be formed as a kind of hand thrown up by us."

We sent these messages to trusted parties (i.a.governments and non governmental organizations, higher placed civil servants, scientific societies) as off about 1996, but it will be no surprise that these messages out of the unexpected corner were almost completely neglected, although on Antarcticconnection.com                                                                                                   one could read during a rather long period a comment on behalf of the paragnost workgroup De Haar concerning "Nasa simulates fly through of ginormous crack in Antarctic glacier, takes you for virtual ride."

My suggestion would be to name the Ice crack phenomenon 'De Haar phenomenon', which is suitable, because to my knowledge he he was the first to describe this phenomenon , and the ice crack was originately seen as haircuts., De Haar means "The Hair". Sometimes one needs a good and recognized paragnost to have a look into future.

Credentials of De Haar  concern paragnostic forecasts (i.a.) the Ozone  gap, Tsjernobyl disaster (1996), the incident with Challenger (1996), the split up of the USSR (1989), the twintowers (2001), the financial and economic crises of 2008 till ?,  the Syria  crisis (2013), the climate change and the role of Antarctic, the crisis between radical Muslim States and the west, (which if this forecast comes out: the west will win at the loss of many lifes, especially Americans, and against heavy costs, WW III ?, being fought out in the south of France ?), todays US racial conflicts (take care !), lookalike problems of that kind in towns in France and in other  European areas).

Laren NH, Gerrit Bogaers, Tuesday 19 August 2014

Scott Turner
Scott Turner

Thanks Dave.


Regarding Pine Island Glacier, it is it's volume that will determine when it will disappear and how much it will contribute to sea level rise.  Volume is made up of 3 components - height, width and length.  Pine Island Glacier is not only losing height but is also losing length.  A similar scenario is occurring at Thwaites Glacier, with the second study mentioned is this article, and available at http://www.sciencemag.org/content/344/6185/735 concluding that early-stage collapse of Thwaites Glacier has begun.  Citing the study's author, this NatGeo article says "Joughin says the breakup of the Thwaites glacier will resemble mechanical failure more than straight-up melting. The ice will slide into the ocean, where it will break off and float away, adding to the volume of water in the sea"


The Shepherd et. al. 2012 article that you quoted is at http://www.sciencemag.org/content/338/6111/1183 and actually has a fair bit of certainty about the ice mass changes in Antarctica.  They say that they achieved greater certainty by combining satellite data sets, and that between 1992 and 2011, the ice sheets of Greenland, East Antarctica, West Antarctica, and the Antarctic Peninsula changed in mass by –142 ± 49, +14 ± 43, –65 ± 26, and –20 ± 14 gigatonnes/year, respectively; and that since 1992, the polar ice sheets have contributed, on average, 0.59 ± 0.20 millimeter/year to the rate of global sea-level rise.


A separate study, published in Geophysical research letters just after the two studies described in this NatGeo article, and available at http://onlinelibrary.wiley.com/doi/10.1002/2014GL060111/abstract analyses Cryosat-2 data and concludes that "Between 2010 and 2013, West Antarctica, East Antarctica, and the Antarctic Peninsula changed in mass by −134 ± 27, −3 ± 36, and −23 ± 18 Gt/year, respectively. In West Antarctica, signals of imbalance are present in areas that were poorly surveyed by past missions, contributing additional losses that bring altimeter observations closer to estimates based on other geodetic techniques. However, the average rate of ice thinning in West Antarctica has also continued to rise, and mass losses from this sector are now 31% greater than over the period 2005–2010."


The thing that matters is where those mass changes have come from and are going to.  If the mass changes are caused by changes in the amount of/rate of snowfall we have less to worry about, but if the mass changes are caused by faster melting and faster sliding into the sea then we should be concerned about the effect on sea level.


The reduced effect of ice that is grounded below sea level due to it being "partially floating", and the fact that you have to melt a LOT of grounded ice to significantly affect sea-level have both already been incorporated in the calculations of sea level rise.


The anthropogenic change in CO2 levels would be better described as an elevation than a pulse.  Despite some of the CO2 we produce being sequestered by the biosphere and the oceans (causing an increase in ocean acidity (or a decrease in ocean alkalinity, if you like) and a resultant drastic effect on marine life and potentially the world's food supply), the rest is predicted to remain in the atmosphere for a very long time.  In comparison to the time scales involved in ice sheet changes, this article and many others actually show that the previous conception of multi-millennium time scales needs to be revised based on evidence of changes occurring across much more rapid time-scales.

Dave Burton
Dave Burton

The article says, "At their current rates of melting, he said, these glaciers would disappear in about two centuries."  But Pine Island Glacier is 2 km thick, and it is losing only about 1 meter per year, which means that at current rates of melting it would disappear in about 2000 years, not 200 -- and Thwaites Glacier is 60% thicker.

In the second place, it's not even clear that Antarctica is losing ice mass, on net. It's very close to being in balance.

ICEsat measurements indicate that, on the whole, Antarctica is gaining, rather than losing, ice mass. Shepherd 2012 concluded that Antarctica ice mass change since 1992 has averaged -71 ± 83 Gt/yr, which means they don't know whether it's actually gaining or losing mass. Zwally 2012 concluded that Antarctic ice mass gained +43 ± 16 Gt/yr (over five years), or +120 ± 50 Gt/yr (over 19 years).

The range of those numbers when the error bars are added is from +170 Gt/yr to -154 Gt/yr, which is equivalent to just +0.47 to -0.43 mm/yr sea-level change. In other words, although we don't know whether Antarctica is gaining or losing ice mass, we do know that the net change is small, and it is having very little effect on sea-level.

Third, the rate of global sea-level rise is extremely low. In fact, it is so tiny that in many places it is dwarfed by land movement. At about 20% of the best tide gauges (which measure long-term sea-level trends) the trend is down (sea-level is falling), because the land is rising faster than the sea.

Fourth, the globally averaged rate of sea-level rise is not increasing, and hasn't increased in over eighty years. In fact, the best studies have found that the globally averaged rate of sea-level rise has actually been decreasing slightly.

We've been putting very large amounts of CO2 into the atmosphere (mostly by burning fossil fuels) for over 2/3 of a century, yet all that CO2 has caused no detectable increase in the rate of sea-level rise. There's no indication in the sea-level measurements that human emissions of CO2 have had any effect at all on sea-level.

Fifth, the disintegration of floating ice shelves has no direct impact on global sea level (ref: Archimedes). The only possible impact is by affecting the rate at which glaciers uphill from the shelves flow toward the sea.

When grounded ice melts or slides into the sea, it does affect sea level rise, but the effect is reduced if the ice is grounded below sea level, i.e., if the rock upon which it rests is below the waterline. In that case, the ice is "partially floating," so the effect on global sea level when it melts or floats away is reduced.

Sixth, the anthropogenic "pulse" in CO2 levels, and its slight resultant warming, will be relatively short, compared to the multi-millennium time scales involved in ice sheet changes. It is doubtful that mankind can sustain current fossil fuel consumption rates and CO2 emission rates for even the next 100 years, and about half of all the CO2 we produce is already being sequestered by the biosphere and the oceans. Mankind will have to find other energy sources within the next century, to sustain civilization. (Right now, one of the most attractive alternatives to fossil fuels is thorium-based nuclear power. It offers the prospect of nearly limitless, affordable energy. But it is quite possible that other energy sources may end up being even more attractive, before fossil fuels become too dear.)

Seventh, it is important to realize that you have to melt a LOT of grounded ice to significantly affect sea-level. Melting an entire cubic mile of ice which is grounded above sea-level would cause global sea level to increase an immeasurably tiny 0.0105 millimeter; if it's grounded below sea-level it has even less effect.

For more information see:

http://wattsupwiththat.com/2014/05/13/the-media-over-hyped-the-west-antarctica-climate-propaganda-reporting/

John Wachter
John Wachter


Sea Ice is water in the ocean that freezes that causes water level to rise temporarily.  

Glacier is added ice to the glass of water which increases the level of water in the glass.

Rising temperatures, increase evaporation and melting of ice. 

Melting allows decay, decay produces Methane, which is 10 times worse the C02.

CO2 is in the atmosphere 100 years verse Methane is about 3-5 years.

These are also offset by the increased trade winds that both increase  evaporation and provides cooling that offsets the increase in temperature.

This article was to provide an insight to the possible glacial changes in  West Antarctic.

.


Mohammed Bentaleb
Mohammed Bentaleb

It is really terifying to know that the glacier is collapcing .It might cause a calamity to the coming generations . Also the heating of the earth is threatening  to the point of making people despair.

Earth First
Earth First

Skimming through the troll denier illogic above, I'm reminded of the LA Times decision to no longer give credence to this same community by printing their letters. Would that it was so simple when they lurk on message boards such as is occurring here.

Personally I find them the equivalent of the type that haunt populist media outlets where the host actually gives them a voice, not shouting them down as occurs on outlets that represent the majority of broadcast space. You've heard the structure if you listen at all, it goes like this, I once believed or supported X, but let tell you what happened my dearest friend or Aunt Tillie, now I don't and neither should you.

As for these boards, difficult as it is to ignore such stupidity, just let them spit in the wind, a wind created by simply ignoring them. Just a thought and with that I'll get back to reading the article.

Damien Chupa
Damien Chupa

So let's now put into perspective what occurred in this "blog" today with another fine analogy by me.  Sitting on the beach one day...nice little island home for all of us. I had just finished talking about waves in general.  How they always come no matter what.  Some big, some small.  Some said big waves never come, some said small waves aren't even waves.  Some were saying waves don't exist.  By some freak chance a small hump appears on the water, distant horizon style.  You're all standing on shore debating how big it is, when its going to strike land, what caused it.  Some conclude it is simply a few whales or dolphins maybe.  You're all there with your science minds trying so hard to wrap your heads around it and get everyone on your side or their side or his side.  Meanwhile the wave is growing and growing on the horizon.  One guy paddled out, came back an hour later and said "YUP...that's a wave alright." ....well yeah...I can see the wave well from up here on top of the mountain....alone, where I built my fancy home.  I didn't see how debating a potential risk was going to save my life. I thought about it long ago and came to my own conclusions.  Potential dangers mixed with potential irrelevancies.... blah, I'll just sit up here, drink what might be my last beer and just hope for the best.  I watched it come in....everyone got swept away.  The water was so high.  I could hear some of the debaters still blaming each other as they rushed passed me, whirling around in their final visit to the water slides.  Nature had run its course.  Survival of the fittest.        Lesson learned?    (I realize this little story won't change a thing or save the world....it's really too bad)      By the way.  My hand is still raised high.  I will do the unthinkable.  I will actually try to save the world.  No clue what it would take, but still, completely willing to roll up my sleeves and get my hands dirty on this....free of charge...even if it kills me.  Have a great day!        

David Seabaugh
David Seabaugh

Sea ice coverage is GROWING in Antartica at a rate of 43,500 square miles a day according to the National Snow and Ice Data Center. This article is entirely misleading. As the global warming alarmist cults' predictive models continue to fail, fewer and fewer people, outside of the media, are willing to accept these ridiculous stories at face value. Wake up editors and read some of the comments below. You are destroying an otherwise great publication by perpetuating this hoax ad naseum.

Julie Clough
Julie Clough

So if we are the ones causing the so called climate change.. who was responsible for the ice age, the massive floods, maybe it was the dinasiours and the cave men that cause  their  extinction millions of years ago!  Yeh my feelings exactly!!!

Peter Stevens
Peter Stevens

Hay is there anyway to stop it from sliding into the ocean? put up a barrier or something?


Counties can all chip in money for this project?



Tom Moore
Tom Moore

This is garbage to believe that Man can cause or even effect any kind of change in the climate. The minute you point out how these so called scientists models are wrong they will adjust them and now their predictions are to regarded as gospel. RUBBISH!!!

K R
K R

larger ocean = more area for fish!

Michael Brunson
Michael Brunson

In the modeling they will need to take into account that the less ice cover there is to reflect solar radiation  the faster the warming will be on the darker sea water. Once a critical mass is reached in this area the quicker the ice will melt. This will cause a vicious cycle of ever increasing ice loss and warmer temperature. This will be incredibly difficult to calculate.


Add this to soot being deposited on the ice on the arctic snow fields and we are in for a catastrophic sea level rise accelerated beyond anything thought imaginable ten years ago. I for one think we have passed the point of critical mass.


The destabilization of Arctic and Antarctic ice will lead to destabilization of the Earth's axis. This will lead to a shifting of the Earth's rotation as seen in the geologic past. The magnetic pole is already drifting towards Siberia and is well documented.


Whether or not people believe in climate change may already be a mute point. The change is happening faster than we can fix. China is the number one leader in producing soot now and only plans to increase the out put.


According to a recent National Geographic article the Atlantic has reversed it's widening in spots and appears to now be contracting. Could this be a product of rising sea levels starting to play havoc with tectonic systems? No one knows.  


What are we to do to stop this speed up temperature rise? I don't know. I have heard we could put vast sheets of reflective spheres in orbit around the planet or that perhaps we could cover vast areas of dessert with a mylar like material to reflect heat back into space. Either could conceivably help. But what would the climate change result be?


I am reminded of the tag line from an old butter commercial, "It's not nice to fool mother nature."

Damien Chupa
Damien Chupa

I've solved the puzzle!!!!  Simply send the ice out into orbit around the earth until we need it for something important like flushing toilets or spitting down the drain.  OR set up pump and a hose and just pump it out to the moon like a flooded basement.  OR develop some massive underground containers and house the extra water there....or above ground who cares.  It's really that simple, but if you've read this far, by now you're thinking I'm about the biggest idiot in the history of all idiots.  "This would be way too expensive" ....is that what you're thinking?  So what is the TRUE problem we have?  Is it climate change or money?  The answer is obvious.  People need to PROFIT as an incentive in this society.  Nobody wants to donate their time to save the world.  A "thank you" from the next group of 7 billion people will NEVER be enough for anyone.  Humanity will not fail because of melting ice.  It'll be the greed.  We're still just acting like apes.  One ape has a shiny stone, the next ape has a big stick.  One ape can't stop looking at the shiny and the other can't stop fearing the stick....and that's all they care about.  I personally would donate my time.  But that's just me....apparently.  The rest of the world can only talk....and hate on people like me.  There is no money to be made in a cure, only treatment.  Just ask the pharmaceutical industry.  We follow their model when it comes to making our planet healthy.  Have a nice stormy not so normal out there anymore...day.

vandal ii
vandal ii

@Earth First ...which is the "because, SHUT UP!" argument, so typical of "consensus science" adherents.  Science is about observation, not determinism - just ask Galileo vs. the Catholic Church.  Science is not about consensus, nor is it *ever* settled (just ask Newton, Einstein, Oppenheimer, et al).  Only politicians, alarmists worried about their jobs and their disciples fear debate.

Jim Balter
Jim Balter

@David Seabaugh If you don't understand the difference between sea ice and glacial (land) ice, you're grossly ignorant and your views are irrelevant (or, actually indicate the opposite of reality).

Carlos De Quevedo
Carlos De Quevedo

@David Seabaugh
David, I live in South Florida...we have some of the lowest elevations in the country.

We are experiencing systematic floods from Key West to Ft. Lauderdale. It started over 30 years ago with periodic flooding in the southern most part of Key West. Now it is almost at every high tide. In Matheson Hammock in Coral Gables, we used to rarely flood when we had a full moon, combined with high tide and easterly breeze. Now we have several events every year. Miami Beach did not flood, now it floods every year.

Ft. Lauderdale never flooded now it floods periodically much like Miami Beach did about 10 years ago. We lost a portion of US1 on one of those floods that occurred with a storm in Ft. Lauderdale. I lived in South Florida most of my life and we didn't have these annual floods which the media has coined as seasonal flooding. Why are we flooding in SoFla?

Mark Gray
Mark Gray

@David Seabaugh  You are talking nonsense. Get your nose out of the those climate crank blogs and learn some science.


Antarctic sea ice is seasonal - it largely melt backs every summer.

Jim Balter
Jim Balter

@Julie Clough So if guns kill people, how did people die before guns were invented?


Your error is known as a fallacy of affirmation of the consequent. This is something that, like most things, you are ignorant of. Over and over on these threads, it can be seen that the deniers are ignorant, dim, intellectually dishonest, and sure of themselves when they have zero reason to be ... typical Dunning-Kruger effect.

Mark Gray
Mark Gray

@Julie Clough Your comment is illogical. The ice ages are caused in part by very small changes in the earth's orbit. That does not preclude current climate change be caused by human's pumping CO2 in the atmosphere.


You argument is equivalent to saying that if someone dies from heart failure, then all deaths must be due to heart failure. It does not make sense

Mike MacFerrin
Mike MacFerrin

@Tom Moore  Oh please.  "Dr. Tim Ball" is paid by the Heritage Foundation.  He retired from being a professor nearly a decade ago, he isn't even current on any research, and wasn't a climate scientist even when he was a professor.  He is nothing more than a hired "skeptic", bought and paid-for by the fossil fuel industry to tell the public what Exxon and Shell want you to hear.

Mike MacFerrin
Mike MacFerrin

@Peter Stevens  I'm not quite sure you're understanding the scale of it.  These glaciers have enough mass behind them to raise sea levels by 4 feet.  4 ft = 1.29 m = 1290 mm of sea level.  It takes 360 Gigatons (billion tons) of water to raise global seas by 1 mm.

360 Gt/mm * 1290 mm equals = 464,500 giga-tons, or 464 trillion tons of ice in these particular glaciers in West Antarctica.

No human structure has ever been built that could hold back such weight, and it'd bankrupt us to even try.  These glaciers grind granite valleys into dust under their weight.  It's not exactly a weekend civil-service project where we can toss a couple hundred truck-loads of sand-bags in front of it or build a wall.

It's a nice thought, but not really gonna work.

Larry Ballard
Larry Ballard

@Tom Moore You are what I like to call wrong...Do you actually think you know more than the many thousands of scientist who have been working on climate change? 

Viktoria Cetinić
Viktoria Cetinić

@Tom Moore so you came here only to write this stupid opinion? 1. check your facts. 

2. there are way more proof of the opposite from your opinion

David Seabaugh
David Seabaugh

@Mark Gray. You are talking nonsense, I am talking facts. Antartic sea ice coverage reached record levels in April, hitting 3.5 million square miles, the largest on record.

Get your nose out of Al Gore's hind end and quit perpetuating this Marxist hoax to destroy the middle class.

Joshua Selvidge
Joshua Selvidge

@Mark Gray @Julie Clough

Mark Gray is talking about Milankovitch cycles.

Some of the current effects of climate change are due to the decrees in axial tilt, but it is so slow and subtle that it won't have the dramatic effects we're seeing right now.


David Seabaugh
David Seabaugh

@Mark Gray. Your comment is illogical. Your argument is equivalent to saying that if someone dies from heart failure, the cause must be something previously unknown to cause heart failure, rather than from a myriad of known causes. It does not make sense.

Earth First
Earth First

@Mike MacFerrin  Thanks Mike, for the rest, the Keeling Curve will be as familiar as the DNA helix. http://keelingcurve.ucsd.edu/

Clicking and viewing the various time frames is more than a little instructive, the full record eg looking like a saw blade adjusted for seasonal variation but always climbing. The overwhelming need for so many to deny the reality of the nose on their face is amazing.

Yes there are cycles then there is the vertical line at the end of largest time frame illustration climbed past 400ppm higher than 600000 year of observed data; only one vector the wise hominid, homo sapiens, sarcasm intended.

Mike MacFerrin
Mike MacFerrin

Correction:  Dr. Tim Ball retired in 1996, nearly two decades ago, not one.

Dave Burton
Dave Burton

@Mike MacFerrin @Peter Stevens  - To be pedantic, it takes 362 gigatonnes, not gigatons, of water melted from grounded ice to raise sea-level by one mm. That's only 328 gigatons (GT).

Nevertheless, you calculated with Gt, so your calculation is correct.

However, that calculation is for melt-water from ice that was grounded above sea-level. But the feature of this region which makes it interesting is that much of the ice is grounded below sea-level.

Fortunately, there's no chance that retreat of the Thwaites grounding line will cause all that ice to flow into the ocean in the next few hundred years. As the grounding line retreats past the ridge, the rate of flow might increase a bit, but as the flow rate increases, the thickness of the glaciers decreases, and as the thickness of the ice decreases the force causing it to flow also decreases - a negative feedback mechanism.

Tom Moore
Tom Moore

@Viktoria Cetinić @Tom Moore  The problem Victoria is that you can not point to any facts. Just models that have been proven wrong time and time again. The fact is is that there is no Global warming taking place and the climate changes taking place cannot be attributed to anything man made. If fact the scientist cannot distinguish between man made C02 and natural. there is far more CO2 produced naturally than man can even begin to produce. 

Mike MacFerrin
Mike MacFerrin

@David Seabaugh  I pointed you to a paper that explains the phenomenon, and rather than using any data to counter it, your entire response amounts to saying "blah blah blah" and more name-calling ("credulous cretins! Marxists!").  Regarding your latest meme of "no warming in 17 years", that's patently false too. See Cowtan & Way (2014, GRL) if you'd like more input.

It isn't difficult to see who's looking at data to form their opinion, and who's responding emotionally with memes they were fed with a spoon.

David Seabaugh
David Seabaugh

@Mike MacFerrin. Blah, blah, blah, blah. Go lecture someone else. I use Marxist and cultist when referring to credulous cretins, like you, because it fits. There has been no warming for 17 years now and I understand why you guys are panicking. You need some lessons in logic and common sense.

Mike MacFerrin
Mike MacFerrin

@David Seabaugh  Sounds like you could use a couple science lessons, lol.

Sea ice does not "destroy" anything in this report, not even a little.  Antarctic sea ice area has been stable (although distribution around the continent has shifted substantially), only showing a slight (non-statistically significant) increase in total area the past 30 years.  Wind patterns have shifted substantially in Antarctica which have caused more floating sea ice to get pushed against the continent rather than drifting out to lower latitudes.  Look up Li, Holland, Gerber & Yoo, 2014 (Nature) for one reference, there are numerous others.  That's the reason for Antarctica's sea ice concentration trends right now, not colder temperatures.

Funny thing is, the same shifting wind patterns that caused the sea ice trends are what's also causing circulation differences that have triggered the collapse of these glaciers, raising sea level.  Seems paradoxical, but it's actually consistent.

Your constant names "cultists! Marxists!" only show how you react emotionally, and have nothing to do with the science.  You're the guy who decided to talk about sea ice in an article about glaciers, while folks needed to explain the difference to you.

David Seabaugh
David Seabaugh

@Mike MacFerrin. I am aware that sea ice is frozen ocean water and glaciers are formed on land from fresh water sources. I certainly do not need a science lesson from you or any other condescending Marxist. The fact remains that sea ice coverage is the largest on record and that fact alone destroys your warming hoax. It's about as logical as saying "it's getting colder therefore it must be warming". Which is exactly what you and your fellow cultist are saying. Really makes you sound like a hack.

Mike MacFerrin
Mike MacFerrin

@David Seabaugh  Sea ice is not glaciers.  I'm sorry you don't understand the difference.

Mark Gray is right, sea ice is seasonal, it's expanding right now in Antarctica in the late fall, just like it does every year before retracting again in the Spring.  Happens every year.

Your argument about sea ice (which again, is not the same thing as the glaciers reported in the NG article above) is about as logical as saying "it got cooler on my porch between 4pm to 10pm today, therefore the earth can't be warming."

Rambling on about "Al Gore's hind" doesn't make you sound convincing.  It just makes you sound like a hack that doesn't know the difference between glaciers (which raise sea levels when they melt) and sea ice (which doesn't).

Mike MacFerrin
Mike MacFerrin

@Always First @Mike MacFerrin

Yep, you're absolutely right.  The Keeling curve is the first and foremost of many lines of evidence that we're changing the workings of our atmosphere in significant ways (the evidence that deniers like to scream "doesn't exist!").  The most telling component of that link is when you click on the "800,000 years" dataset in the graph, and look at the current trend compared with eight-hundred previous millennia.  It's a rather stark difference.

Karen Harsin
Karen Harsin

How about Katrina for proof , flooding and rising water all along the east coast where there hasn't been any since records have been kept.  Hurricane Sandy which flooded NYC which has not flooded ever to the extent it did this time even with past storms. Especially South Fla as someone pointed out Key West floods all the time now and has standing water at the airport where it had none, ever.   We as a species have been on this planet less time than the dinosaurs and have managed to change the climate with our industrialization faster than any known species ever. You don't have to be a scientist to see that our planet is changing at an accelerated rate, If you can't see that then you are blind and dumb.  @Viktoria Cetinić  

Mike MacFerrin
Mike MacFerrin

@Tom Moore @Viktoria Cetinić  You couldn't possibly be more wrong, Tom.  There are bucketloads of direct measurements and evidence all around, and it keeps coming in daily.  Do you think those satellites are up there just to put pretty lights in the sky?  I don't know where you guys get your "there's no data" meme, that couldn't be further from the truth.

James H.
James H.

@Tom Moore


Tom, what are three, well-founded, irrefutable facts that discredit anthropogenic global warming/climate change? :-)


Provide the best of the best evidence?

Jim Balter
Jim Balter

@David Seabaugh = severe Dunning-Kruger effect. He has no grasp of how obviously dim he is to those who aren't.

Dave Burton
Dave Burton

@Mike MacFerrin - Actually, sea ice around Antarctica could be significant in this context, for a couple of reasons.

For one thing, ice cover stills the water beneath the ice, potentially reducing heat transfer and melt from the adjacent ice sheets.

OTOH, ice cover also reduces evaporation and evaporative cooling of the water beneath, and because it reduces evaporation it also reduces snowfall, which reduces ice buildup on nearby land.

You are right, though, that wind patterns are a major factor in sea ice trends. But they are an even bigger factor in the Arctic, where there's no central land mass, than they are in the Southern Ocean.

Yet most climate alarmists never mention wind when talking about Arctic sea ice, which is down a bit. So why are they quick to bring up wind when talking about Southern Ocean sea ice, which is up a bit?

The most important thing to keep in mind is that, despite seven decades of heavy CO2 emissions, the globally averaged rate of sea-level rise hasn't increased at all. Elevated atmospheric CO2 levels, due to human activity, have had no detectable effect on sea-level.

Ref: http://www.sealevel.info/

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