ICESAT Data Shows Mass Gains of the Antarctic Ice Sheet Exceed Losses

ICESat’s orbit was designed to maximize coverage over the great polar ice sheets, such as Antarctica, where ground tracks overlap to create an intricate grid of data points. Image: NASA GSFC

The results of ICEsat measurements are in for Antarctica, and it seems those claims of ice mass loss in Antarctica have melted now that a continent wide tally has been made. This was presented in the SCAR ISMASS Workshop in Portland, OR, July 14, 2012 and was added to NASA’s Technical Reports server on September 7th, 2012. H/T to WUWT reader “Brad”. What’s interesting (besides the result) is that the report was prepared by Jay Zwally, whose “ice free Arctic by the end of summer 2012” prediction is about to be tested in 12 days.  It also puts the kibosh on GRACE studies that suggested a net loss in Antarctica. Note there’s the mention of the “climate warming, consistent with model predictions” at the end of the report. They’d say the same thing if ICEsat had measured loss instead of gain, because as we’ve seen before, almost everything is consistent with warming and models no matter which direction it goes.

Here’s the video presentation. The report abstract follows.

Mass Balance of the Antarctic Ice Sheet 1992-2008 from ERS and ICESat: Gains exceed losses – Presented by Jay Zwally, NASA Goddard, USA ISMASS 2012 is an activity of the renewed SCAR/IASC ISMASS expert group, which focuses on the mass balance of ice-sheets and their contribution to sea level changes. The workshop is sponsored by ICSU, SCAR, IASC, WCRP, IGS, and IACS with support from CliC and APECS. Video recording and editing provided by Kristin Poinar, Mai Winstrup, and Jenny Baeseman

Mass Gains of the Antarctic Ice Sheet Exceed Losses

Zwally, H. Jay; Li, Jun; Robbins, John; Saba, Jack L.; Yi, Donghui; Brenner, Anita; Bromwich, David

Abstract:

During 2003 to 2008, the mass gain of the Antarctic ice sheet from snow accumulation exceeded the mass loss from ice discharge by 49 Gt/yr (2.5% of input), as derived from ICESat laser measurements of elevation change. The net gain (86 Gt/yr) over the West Antarctic (WA) and East Antarctic ice sheets (WA and EA) is essentially unchanged from revised results for 1992 to 2001 from ERS radar altimetry.

Imbalances in individual drainage systems (DS) are large (-68% to +103% of input), as are temporal changes (-39% to +44%). The recent 90 Gt/yr loss from three DS (Pine Island, Thwaites-Smith, and Marie-Bryd Coast) of WA exceeds the earlier 61 Gt/yr loss, consistent with reports of accelerating ice flow and dynamic thinning. Similarly, the recent 24 Gt/yr loss from three DS in the Antarctic Peninsula (AP) is consistent with glacier accelerations following breakup of the Larsen B and other ice shelves. In contrast, net increases in the five other DS of WA and AP and three of the 16 DS in East Antarctica (EA) exceed the increased losses.

Alternate interpretations of the mass changes driven by accumulation variations are given using results from atmospheric-model re-analysis and a parameterization based on 5% change in accumulation per degree of observed surface temperature change. A slow increase in snowfall with climate warming, consistent with model predictions, may be offsetting increased dynamic losses.

Click to View PDF File [PDF Size: 256 KB]

Looks like “Skeptical Science” will have to update their reliance on the “Cophagen Diagnosis” as well as their claim of “Antarctica is losing land ice as a whole, and these losses are accelerating quickly.”:

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Figure 2: Estimates of Total Antarctic Land Ice Changes and approximate sea level contributions using many different measurement techniques. Adapted from The Copenhagen Diagnosis. (CH= Chen et al. 2006, WH= Wingham et al. 2006, R= Rignot et al. 2008b, CZ= Cazenave et al. 2009 and V=Velicogna 2009)

Estimates of recent changes in Antarctic land ice (Figure 2) range from losing 100 Gt/year to over 300 Gt/year. Because 360 Gt/year represents an annual sea level rise of 1 mm/year, recent estimates indicate a contribution of between 0.27 mm/year and 0.83 mm/year coming from Antarctica. There is of course uncertainty in the estimations methods but multiple different types of measurement techniques (explained here) all show the same thing, Antarctica is losing land ice as a whole, and these losses are accelerating quickly.

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I’m glad that’s finally settled.

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Polar Amplification means the temperature in polar areas move faster during both cooling and warming period. This is attributed to the positive feedbacks from the retreat of ice and snow and other lesser reasons, but there are the extra factors currently not acounted for.
http://www.vukcevic.talktalk.net/PA.htm

You see? Data shows there’s no reason for alarm.

Juraj V

Yikes! Global warming is moving ice from the North to the South Pole! If we don’t rein in emissions within 10 years, the planet will reach a tipping point, I mean it will literally tip over. Or maybe not, but with all that ice in Antarctica Earth could get too heavy and fall from orbit!
Please send me 25 gigadollars and I’ll provide a solution to the underlying problem.

Peter Miller

Yet another inconvenient truth.
Hey Al – any comment?

As I said: by 2035 all the ice in arctic will also be back.
But……do we really want the cold? Why not add more CO2?

kwinterkorn

Every discussion of ice loss in the Arctic which references “global” warming or climate change is incomplete unless it includes at least a mention of the “global” ice balance. The current low ice levels in the Arctic seem to be balanced by the increases in the Antarctic. This strongly suggests that the Arctic changes reflect a global shift of heat energy from the northern hemisphere to the southern. Ocean currents suggest themselves as a unifying explanation.
Occam’s razor says one should look for the one explanation that explains all data. Sometimes Occam does not apply, but it should always be considered as a part of good science. To say that the Arctic ice loss is due to CO2-related AGW, but that the ice increase in the Antarctic is due to something else, defies this time-worn principle.

Jimmy Haigh

Mosher?

from article: It also puts the kibosh on GRACE studies that suggested a net loss in Antarctica. Note there’s the mention of the “climate warming, consistent with model predictions” at the end of the report. They’d say the same thing if ICEsat had measured loss instead of gain, because as we’ve seen before, almost everything is consistent with warming and models no matter which direction it goes.
I read ScienceDaily and Science New sites daily, and I’ve noticed for years the use of the statement and its ilk as cited above for climate articles [but not limited to that direct subject] as they satisfy or pander or prostitute for funding.

Elizabeth

Jurav V Its incredibly stable (The temperature variation), quite a surprise. I would not be surprised that this applies to the whole globe once you take away all the “adjustments”

fredb

I think a closer read is needed: from the abstract I note “Imbalances in individual drainage systems (DS) are large (-68% to +103% of input), as are temporal changes (-39% to +44%). The recent 90 Gt/yr loss from three DS (Pine Island, Thwaites-Smith, and Marie-Bryd Coast) of WA exceeds the earlier 61 Gt/yr loss, consistent with reports of accelerating ice flow and dynamic thinning.”
What this says to me is that changes are going on in the dynamics … its not only a simple matter of net mass loss or gain … it as important to consider the changing dynamics of the system.

richcar 1225

This result in consistent with the Jason GMSL data which if graphed as a rate of changle in GMSL and plotted as 12 month average reveals that the rate has dropped from 4 mm/yr to almost zero now since 1998.
This plot is on the climate for you site under the oceans section. http://www.climate4you.com/index.htm
Interestingly the graph can not be found on any of the sea level sites. With SST roughly flat over this period (thermal expansion component small) mass must be being gained somewhere and Antarctica with record cold temps and record cold southern ocean SST must be the place). July temps in Antarctica were as much as 10 degrees below normal. http://www.climate4you.com/images/ANTARCTIC%20Temp%20201207%20versus%201998-2006%201200km.gif

cui bono

So, problem solved. All we need is a huge pump and a pipeline connecting the two poles, and then we redistribute the white stuff.
Geoengineering 101.

Pamela Gray

hmmm. So snow increase is due to AGW. Who would have thought land ice mass increases with anthropogenic global warming? Such a sad thing. Tsk, tsk. Wonder what caused mass to grow before? Since the article seems to imply that AGW snow (something children are not supposed to know about?) is causing it now sooooo something else must have caused it back then, do you suppose it was the Ice Queen whut dun it?
Seriously, snow is a weather event. The only way snow occurs is if the weather sets it up to snow. Weather caused it back then, and weather is causing it now. Weather, within climate boundaries has both short term and long term pattern variations. And sometimes, these weather pattern variations kill and sometimes they allow life to bloom. My hunch is that both sides of the coin are necessary to sustain planetary life. Drought and rain, cold and warm, ice and melt.
The problem is that humans tend to only believe what they themselves wish to learn. We hardly consider the learning of those that have come before, believing their knowledge to be quaint and outdated. In other words, we do not learn from the past and we do not increase in wisdom because of it. We only go round in circles.

Louis Hooffstetter
Don Keiller

Bet this news will not adorn the front cover of Nature (a la Steig), neither will it feature on MSM or, indeed, AR5.

Birdieshooter

Am I reading this right ?..” Because 360 Gt/year represents an annual sea level rise of 1 mm/year, recent estimates indicate a contribution of between 0.27 mm/year and 0.83 mm/year coming from Antarctica.” So that means Antarctica may contribute as little as about an inch per century to sea level rise?

aaron

Another negative feedback mechanism. As ice moves to the southpole, it will tip toward the sun and increase albedo when earth is closest to the sun.

Steve from Rockwood

I think I’ve got it now. When the ice is melting, it’s catastrophic global warming. When we’re gaining ice mass, it’s consistent with global warming. At first it didn’t make sense, but if you repeat it often enough, it just rolls off the tongue.

Kev-in-Uk

Birdieshooter says:
September 10, 2012 at 8:39 am
LOL – Yeah, but it is only a small area, the Arctic is the BIG worry…….all that FLOATING ice…..
/sarc

pat

Like Guam with too many military personnel, Antarctica faces the prospect of tipping over on account of its unbalanced ice fields. Just as predicted by all the models.

Kasuha

One has to appreciate they’re honest. If they find the ice is decreasing, they report the ice is decreasing. If they find the ice is increasing, they report the ice is increasing. If they can’t match the data from different sources, they report they can’t match the data. That’s ok by me, that’s how science is done.
Both ICEsat and ERS measure the surface altitude and subsequently the volume, not really the mass. GRACE measures total mass. They only contradict each other based on a number of assumptions, such as that the ice density doesn’t change. One of possible mechanisms for Antarctica to gain ice and to lose mass at the same time would be that there may be numerous caverns filled with water all over the Antarctis and they are now freezing over, increasing the total volume without adding to mass … accompanied by overall loss of mass all around the edge. But I’m no scientist to place such hypotheses.
And of course, there’s no wonder they find models that agree with observations. It’s long known fact that a guaranteed way how to get a successful forecast is to generate sufficient number of different forecasts. Our climate modellers have been very active in that direction in recent years.

Gunga Din

It’s that time of year. Spring and Fall as the Northern and Southern hemispheres prepare to switch seasons, contradictory predictions are made by the CAGWers about what will happen at the poles due to Man’s CO2 emissions. At the end of winter/summer the prediction that most closely matches what is actually observed will be trotted out as proof we need to shut down more power plants and spend more money to research the “crisis”. (Sometimes “actually observed” is on a computer screen rather than actually measured.) Whichever end is melting usually gets the most press. Bogus predictions are forgotten (except for places like WUWT) or explained away.

rogerknights

This benchmark means GRACE will have to re-tune itself. When that happens, what other measurements will have to be readjusted? Someone should keep after them about this.

Billy Liar

Birdieshooter says:
September 10, 2012 at 8:39 am
Am I reading this right ? … So that means Antarctica may contribute as little as about an inch per century to sea level rise?
Yes, but think of the children: how will they cope with a disaster of such extreme seriousness?

Wait, the data has not been “corrected” yet. I give it 2 months – a new paper will come out of the pseudoscience mills showing almost exactly the opposite.

Kev-in-Uk

Billy Liar says:
September 10, 2012 at 9:59 am
Don’t worry – they will all go back to the 70’s – platform shoes!!!

William

Zwally et al’s analysis is based on laser measurement of the elevation of the Antarctic ice sheet. Analysis of that data indicates the Antarctic ice sheet is gaining mass.
If the Antarctic is gaining mass how does one explain increasing sea level from the GRACE satellite measurements and decreasing Antarctic mass from the GRACE measurements? The GRACE satellite measures mass indirectly by measuring changes in altitude as the GRACE satellite pair move about the earth.
It has been known for sometime by the US and Russian intercontinental missile testing results that something inexplicably effects missile trajectory which requires mid launch correction for precision impact results. The something that changes missile trajectory is the sun. The suns effect on low level satellite orbits is the same reason (same mechanism) that is causing a sudden increase in earthquakes and volcanic eruptions.
There is past correlation of periods of very low solar magnetic cycle activity and increases in volcanic activity. The question is why? What is the mechanism? If I understand the fundamental mechanism and its manifestations, there will be a significant increase in volcanic activity and there will be a significant drop in temperatures particularly at high latitude regions, as we are experiencing an interruption in the solar magnetic cycle. (There are coincidentally a host of new astrophysical papers that can be used to explain the mechanism and provide observation evidence that the mechanism exists. I am working away on that subject and will have something ready if there is clear observational evidence that the solar magnetic cycle has been interrupted as well as earth based anomalies that require explaining.)
The GRACE measurement change has nothing to do with mass change. The ocean levels have not been changing. Analysis of data from tidal gauges at multiple locations does not support a rise in ocean level.
http://www.21stcenturysciencetech.com/Articles_2011/Winter-2010/Morner.pdf
In an interview and paper published in 21st Century in 2007, I have shown that global sea level is not in an alarming rising mode, which is the main threat in the International Panel on Climate Change scenario. If sea level is not rising at a high rate, there is no serious threat and no real problem. In subsequent papers, I continued to present new data on sea level stability. In Mörner 2007b, our field observational database from the Maldive islands was described in detail. A new study in Bangladesh was published in 2010 (Mörner 2010a). New data with respect to general sea level changes were published in another paper (2010b). The interview and article appear in the Fall 2007 21st Century THE GREAT SEA-LEVEL HUMBUG There Is No Alarming Sea Level Rise! by Nils-Axel Mörner One of the approximately 1,190 beautiful coral islands that comprise the nation of the Maldives. As Mörner shows, the Maldives are not in danger of inundation. …short sea level booklet titled “The Greatest Lie Ever Told” (Mörner 2007c) was updated in new editions in 2009 and 2010. Here I will investigate the proposed rates of sea level changes by IPCC and others….
The interview is available online at
http://www.21stcenturysciencetech.com/Articles%202007/MornerInterview.pdf

Eustace Cranch

Ice sheet? Pshaw! We need to know what’s really important: any Shoggoth sightings at the Mountains of Madness?

As near as I can tell, what this is saying is that lower elevation areas and areas near the coast susceptible to global warming are losing mass, and higher elevation areas that see little or no melt but do receive increased precipitation along with warmer temperatures (albeit still below freezing), are seeing net gains in mass. Both results are from global warming.
There is no “balance” however with mass gains in the Antarctic and Ice losses in the Arctic. In a little over 30 years, 75% of summer Arctic ice volume has been lost. This leads to less reflectivity and increased temperatures, further continuing the warming cycle.
I’m curious to see if the future “cooling” some of the writers on here discuss occurs or if predicted “cooling” is simply absorbed and overwhelmed by the ongoing warming activities of man.

richcar 1225

Glaciers will grow and surge with increased snowfall. Warmists speculated that warm sea surface temperatures would raipidly melt the glaciers as they entered the Southern Ocean and cause them to surge by melting buttresses. So how is the warm Southern Ocean theory holding up ?
http://bobtisdale.files.wordpress.com/2012/08/13-southern.png

Kelvin Vaughan

No chance of an ice free Arctic. It’s been refreezing at the webcam since the begining of August.
So even if the edges are still melting that area is freezing up.

Man Bearpig

So global warming is now causing ice mass increases? … are we all going to die again ?

Kev-in-Uk

johnp says:
September 10, 2012 at 10:41 am
Of course there is no ‘balance’ between the north and south poles. For a start the south pole is over land, and a BIG land mass too – whilst the north pole is over the ocean and affected by warming currents and wind movements.
The two differences do show clearly how land mass ice and floating ice differ in their climate responses. Your assumption the Arctic warming and ice loss as manmade is unproven – and the lack of significant widespread warming in the antarctic confirms this to some extent (unless you happen to subscribe to the view that all the CO2 rises to the north pole?!!). In a nutshell, the arctic ice loss may be entirely natural, as may be the variation in the antarctic – you simply cannot prove that CO2 is the cause.
All the Arctic ice situation really shows us, is that the sea and air currents have been changing enough to cause melt – why is not clear, but we do certainly know that Arctic ice has been low in the past (before the era of CO2) and hence the current state may well be a natural ‘event’.

richcar 1225

The problem with Grace is that gravity not only has unknown varibles like density and volume but must also be corrected for GIA (Global isotatic adjustments} that are still occuring as a result of the last ice age ending. Geodetic data (gps) and sesmic velocity surveys are being used to constrain solutions to the problem As more data becomes available we are suprised to learn that Greenland’s center for instance is actually depressing the crust not rebounding like the edges or the rest of the Northern Hemisphere. Antarctica is even more problematic because of the lack of geodetic data.

anarchist hate machine

Yes, ice is INCREASING. There goes that asinine ‘it’s losing ice’ argument down the toilet.

J Martin

William.
Vukcevic for one will be more than a little interested in your magnetic / temperature hypothesis.
Vuk does have an interesting graph on the subject himself.
http://www.vukcevic.talktalk.net/NFC1.htm
Any chance of an article on WUWT in the not too distant future ?

Maus

vukcevic: “This is attributed to the positive feedbacks from the retreat of ice and snow and other lesser reasons, but there are the extra factors currently not acounted for.”
Interesting bit at your link, thanks for posting it. Though I’m a bit at a loss as to whether or not the non-linear relation between W/m^2 and Kelvins is acknowledged in the standard account. All things being equal, small flux changes due wind and water currents will have a larger T delta at the poles rather than at the equator. Due the axial tilt this should exacerbate things beyond the Arctic and Antarctic circles.
kwinterthorn: “Every discussion of ice loss in the Arctic which references “global” warming or climate change is incomplete unless it includes at least a mention of the “global” ice balance. ”
Nonsense. We know the MWP was global by looking only in the Northern Hemisphere. ::dives in the bunker::
johnp: ” This leads to less reflectivity and increased temperatures, further continuing the warming cycle.”
I know that’s the standard line and it would be nice if things were that simple. But if you rip out some standard trig on the equinoxes and solstices with the axial tilt included you find that things are not necessarily what they should be given the interaction of the angle of incidence on open water versus sea ice. It takes about 5 minutes to punch the values through yourself and you can get the relevant numbers from here to get you started: http://en.wikipedia.org/wiki/Albedo
The singular difficulty is that at high angles of incidence, as found above the Arctic and Antarctic circles, the reflectivity of water can trivially exceed the albedo of ocean ice. This doesn’t mean the standard account is wrong per se, but that there are trivial issues that are not often spoken about.

adolfogiurfa

Did someone called AL go down there in recent times? 🙂

JohnP says
In a little over 30 years, 75% of summer Arctic ice volume has been lost
Henry says
you ignored the hadcrut 3 results shown by Smokey?
My results show double, i.e average temps have gone down by 0.2 degrees C since 2000.
I also predict all ice lost in the arctic being back by 2038.
(it was the same in 1920, and all ice was back by 1940) http://wattsupwiththat.com/2012/09/06/soon-and-briggs-global-warming-fanatics-take-note-sunspots-do-impact-climate/#comment-1074407

Maus says:
September 10, 2012 at 12:38 pm
kwinterthorn: “Every discussion of ice loss in the Arctic which references “global” warming or climate change is incomplete unless it includes at least a mention of the “global” ice balance. ”
Nonsense. We know the MWP was global by looking only in the Northern Hemisphere. ::dives in the bunker::

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Naw, we know the MWP was a global phenom by looking at global proxies.
http://pages.science-skeptical.de/MWP/MedievalWarmPeriod.html

Bill Parsons

fredb says:
September 10, 2012 at 8:13 am
I think a closer read is needed: from the abstract I note “Imbalances in individual drainage systems (DS) are large (-68% to +103% of input), as are temporal changes (-39% to +44%). The recent 90 Gt/yr loss from three DS (Pine Island, Thwaites-Smith, and Marie-Bryd Coast) of WA exceeds the earlier 61 Gt/yr loss, consistent with reports of accelerating ice flow and dynamic thinning.”
What this says to me is that changes are going on in the dynamics … its not only a simple matter of net mass loss or gain … it as important to consider the changing dynamics of the system.

I’m not a scientist, but I believe they measured the gain in height from satellites, converting that to a mass figure from know snow-and-ice water content analyses, perhaps done on the ground. Don’t know how they compute total run-off from the three major drainages, but they show a net mass gain resulting from the difference, give or take a few billion tons.
I’d like to make two points: One is that, given the embarrassment of making a public correction to his earlier study (especially in the direction of a higher net positive), one might surmise that Zwally is pretty sure of his numbers this time ’round. There’s been a net gain. Second, I think this makes sense if the much heralded warming influences of the last year were real. Atmospheric warming would carry more moisture over the interior, depositing greater amounts of (wetter) snow, which would increase the run-off during its compaction.

Otter

James Sexton, THANKS for that map! Now added to my array of artillery.

Quiet Professional

But what about ice quality?

Gunga Din

Man Bearpig says:
September 10, 2012 at 11:13 am
So global warming is now causing ice mass increases? … are we all going to die again ?
=====================================================================
Yes, but now we’re all going to freeze to death from the heat. 😎

Andrejs Vanags

I read somewhere that the antartic is so cold that there is almost no humidity there and almost no precipitations, and that if the antartic where to ‘warm’ from very negative temps to mild negative temps then there would be a net gain in ice mass since then there would be an increase in humidity and precipitation, but no net increase in ice melting since the temperatures would not reach that point yet. On the other hand, temps on the artic are on average much warmer and further warming results in ice loss due to melting. So everything is consistent with increased overall world temperatures: the antartic ice sheet grows and and the artic one retracts.

IanG

According to the European Centre for Medium-Range Weather Forecasts http://www.ecmwf.int/publications/cms/get/ecmwfnews/1347007442577 , as reported by the BBC, http://www.wwfblogs.org/climate/content/bbc-more-evidence-declining-arctic-sea-ice-and-warming-north-atlantic-disrupt-weather
Then the ice extent in the Arctic during the melting season of 1912, was even less than today .
Apparently the loss of Arctic Sea Ice caused the almost record breaking rainfall on the UK during the summer of 2012, only exceeded by the rainfall of 1912.
How on earth did the arctic manage to recover in time for the satellites to see a maximum extent in 1979? Could it be that the sea ice extent cycles periodically, no matter how many humans are exhaling?

jones

omnologos says:
September 10, 2012 at 7:44 am
Yikes! Global warming is moving ice from the North to the South Pole! If we don’t rein in emissions within 10 years, the planet will reach a tipping point, I mean it will literally tip over. Or maybe not, but with all that ice in Antarctica Earth could get too heavy and fall from orbit!
Please send me 25 gigadollars and I’ll provide a solution to the underlying problem.
Almost ruined my computer with my mouthful of coffee with that one…Ta…..

The amount of ice on the polar caps has NOTHING to do with the IMAGINARY increase / decrease in GLOBAL temp; but depends on the availability of raw material, for renewal of the ice deficit. Yes, ice deficit is created by the geothermal heat on tera firma – by the salty currents on the water.
Average temp on the the polar caps is minus -30C, that’s twice as cold than in your deep freezer.. Water freezes at ZERO C!!! Misleading the public that: the amount of ice on the polar caps is dictated by the non-existent phony GLOBAL warmings; is a smokescreen, to get you further and further away from the reality. Anybody interested in the truth, reality, on my blog: http://globalwarmingdenier.wordpress.com/2012/09/10/global-temperature/