Antarctic Ice is Growing

I've been searching for an explanation of this and I finally stumbled upon a two references that provides some likely mechanisms.

Increasing Antarctic sea ice under warming atmospheric and oceanic conditions
Author(s): Zhang JL (Zhang, Jinlun)
Source: JOURNAL OF CLIMATE Volume: 20 Issue: 11 Pages: 2515-2529 Published: JUN 1 2007

Abstract: Estimates of sea ice extent based on satellite observations show an increasing Antarctic sea ice cover from 1979 to 2004 even though in situ observations show a prevailing warming trend in both the atmosphere and the ocean. This riddle is explored here using a global multicategory thickness and enthalpy distribution sea ice model coupled to an ocean model. Forced by the NCEP-NCAR reanalysis data, the model simulates an increase of 0.20 x 10(12) m(3) yr(-1) (1.0% yr(-1)) in total Antarctic sea ice volume and 0.084 x 10(12) m(2) yr(-1) (0.6% yr(-1)) in sea ice extent from 1979 to 2004 when the satellite observations show an increase of 0.027 x 10(12) m(2) yr(-1) (0.2% yr(-1)) in sea ice extent during the same period. The model shows that an increase in surface air temperature and downward longwave radiation results in an increase in the upper-ocean temperature and a decrease in sea ice growth, leading to a decrease in salt rejection from ice, in the upper-ocean salinity, and in the upper-ocean density. The reduced salt rejection and upper-ocean density and the enhanced thermohaline stratification tend to suppress convective overturning, leading to a decrease in the upward ocean heat transport and the ocean heat flux available to melt sea ice. The ice melting from ocean heat flux decreases faster than the ice growth does in the weakly stratified Southern Ocean, leading to an increase in the net ice production and hence an increase in ice mass. This mechanism is the main reason why the Antarctic sea ice has increased in spite of warming conditions both above and below during the period 1979-2004 and the extended period 1948-2004.

This is one of the reasons I enjoy studying climate change. I would have previously said "if it get's colder you'll get more ice and if it gets warmer you'll have less". But because of the complex dynamics of near surface ocean circulation, it's not nearly that simple.

The other part of the explanation has to do with increases in snow fall. As the Antarctic warms there is more humidity in the air and this tends to fall as snow. Snow on ice will either insulate and increase melt or at a threshold help the ice grow.

Effects of snow depth forcing on Southern Ocean sea ice simulations
Author(s): Powell DC, Markus T, Stossel A
Source: JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS Volume: 110 Issue: C6 Article Number: C06001 Published: JUN 1 2005

Abstract: [1] The aim of this study is to investigate the competing effects of a snow layer's insulation and snow-ice formation on thermodynamic sea ice thickness growth in response to changes in precipitation. Using optimal interpolation to assimilate Special Sensor Microwave/ Imager satellite-derived snow depths into a dynamic-thermodynamic sea ice model, we create a daily assimilated snow depth product for the years 1992 - 2003. The assimilated snow depths are used to adjust National Centers for Environmental Prediction/ National Center for Atmospheric Research reanalysis precipitation rates which subsequently force the model's snow depths and freshwater input. These adjusted precipitation rates are used to create a best estimate snow depth climatology. This climatology provides the basis for a series of sensitivity experiments. Precipitation rates are varied from 0.0 to a doubling of the present day precipitation. Initially, sea ice volume decreases with increasing precipitation rate multiplying factor (PRMF) because of the insulation effects of a deeper snow layer. The turning point at which the insulation effect becomes balanced by the snow to ice conversion effect ranges from PRMF = 0.50 to PRMF = 0.75, depending upon the snow thermal conductivity and density. This suggests that with present-day precipitation rates the snow effect on Southern Ocean sea ice is dominated by snow-ice formation rather than the snow's insulation.

thanks for those very interesting abstracts, streamtracker! I will point them out in a new post early next week.

It's all rather funny and smacks of desparation.

First, any argument that tries to use a regional phenomenon to disprove a global trend is simply dead in the water.

Quite right. Why aren't you attacking people who keep refering to melting of ice in the north 'artic'? [Artic is a term that covers both poles] Perhaps it is because it's useful to selectively use examples that reinforce your beliefs.

PS I'll use it as a skeptic

We need to assess the balance of the evidence.

Quite. Global average temperate anomalies just went negative. On balance there is no global warming

Secondly, the phenomenon of thickening of an ice sheet is not by itself inconsistent with warming!

So what happened to all the alarmism about melting ice caps and rising sea levels? This is an example of an inconvient truth, but strong evidence for the complete unreliability of climate science.

The hard evidence is that when we look at the temperature records from people like RSS who use satelites and not dodgy measurement devices next to air con outlets, the world has cooled.

Secondly, if we compare the forecasts against the temperature record, we can falisfy the forecasts with a very high degree of confidence, on 10, 20 years timescales.

If you can't get things right with a 10, 20 year forecast, you're having a laugh saying you can get it right on a 30, 40, 50 year timescale

So Nick, you think these scientists got a call from Al Gore, telling them to come up with some sort of explanation? Or is it maybe just the fact that nature is complicated?

Global average temperature anomolies did not "just go negative". Just check CRU or NASA GISS temperature records. The smoothed trend anomaly is around .4oC above the 1960-91 global mean (a href="http://www.cru.uea.ac.uk/cru/info/warming/">here). You are probably just refering to the short term plateau we are in, but it is just not long enough to draw the conclusion that anything is different from expectations. Climate is defined as the 30 yr average of weather, so 10 years, (especially 10 years starting with an extreme high data point!) of no rise is not long enough. No record shows 30 yr cooling.

10-20 years is borderline between weather and climate, we are trying to describe the climate. So no, you are exactly wrong that being off on the short term means you can forget the long term.

See also this article about weather vs climate prediction..

Growing Antarctic ice may not be evidence against global warming--but it is an argument against rising sea levels, isn't it? A lot of laypeople (like myself) have no quarrel with the concept of global warming--it's the postulated effects that sound extreme. I didn't really have a problem with the global warming thing until people started making obviously absurd statements like 'if we don't change everything this decade we're all doomed.' That actually got me to read the latest IPCC report--not the politician's summary. I must say the more extreme alarmists regarding global warming cost the entire movement a lot of credibility.

Hi Tom,

Sea level rising is a non-controversial observation, so I don't think any ice observations can "argue against" that. It is however part of the equation of where the rising levels come from. I think it is becoming more an more clear that the loss of ice in Greenland is more than making up for any gains in the Antarctic. There are also two major ice sheets in the antarctic, east and west. The EAIS is thickening and the WAIS may be thinning, findings are preliminary (I am probably a bit out of date about this...)

But regardless of the above, the majority of SLR is the result of thermal expansion due to warming waters.

With respect to the IPCC, I fully applaud going to that source over news reports, alarmist or denialist. I would also observe that due to its nature (large committee style organization, searching for areas of consensus) it tends to be vey conservative in its statements and predictions. What is happening in Greenland and the arctic in general is well off the scale of anything they predicted and the IPCC does not include the latest research and observations.

Otherwise, I can not argue with your observation that "the more extreme alarmists regarding global warming cost the entire movement a lot of credibility"

Hi Coby,

Thanks for the quick response. I think if those committed to combatting anthropogenic contributions to global climate change would actually stand up and point to some of the more outlandish statements and say 'the science doesn't suggest this to be the case,' they (and the rest of us) would all be better off.

Sorry but i am siding with Nick here (no suprise) you make this statement "First, any argument that tries to use a regional phenomenon to disprove a global trend is simply dead in the water. Anthropogenic global warming theory does not predict uniform warming throughout the globe."

How convenient for you that you do not predict uniform GW which of course comes with the added claus "GW means Global cooling which is why the ice is thickening".

The only time i have seen AGW proponents such as yourself make absurd claims like the above is always post facto. Can you please give me a link which shows anyone making the following claims

A symptom of GW is GC (more ice in antarctica)

The temperature will reach a climax in 1998 due to a strong El Nino, the temp will then drop back down to X levels (does not have to be accurate) due to a La Nina but then GW will be back in 2015.

Rising temps of the past have been caused by the M Cycle effect

prior to lets say 1995? i will even accept 1998 OK

Sorry but i am siding with Nick here (no suprise) you make this statement "First, any argument that tries to use a regional phenomenon to disprove a global trend is simply dead in the water. Anthropogenic global warming theory does not predict uniform warming throughout the globe."

How convenient for you that you do not predict uniform GW which of course comes with the added claus "GW means Global cooling which is why the ice is thickening".

The only time i have seen AGW proponents such as yourself make absurd claims like the above is always post facto. Can you please give me a link which shows anyone making the following claims

A symptom of GW is GC (more ice in antarctica)

The temperature will reach a climax in 1998 due to a strong El Nino, the temp will then drop back down to X levels (does not have to be accurate) due to a La Nina but then GW will be back in 2015.

Rising temps of the past have been caused by the M Cycle effect

prior to lets say 1995? i will even accept 1998 OK

Crakar14- There isn't global cooling. The overall trend since the industrial age has been warming. Please see here for more information: http://data.giss.nasa.gov/gistemp/2008/ . You'll note that, while 2008 has been the coolest year since 2000, the trend still increases. One year is simply too small a time frame to measure. It is this point that the post was trying to make: Regional phenomena does not disprove a global trend. One year of cooler temperatures, along with more snow in Wagga Wagga, does not prove that the planet isn't warming.

Second, global warming increases precipitation, since more water is available for evaporation. This also causes an increase in snow. However, Antarctic ice has been compacted over hundreds of thousands of years, so three inches of snow doesn't replace three inches of Antarctic ice. This is apparent because ocean water levels continue to rise, even while more snow falls. You should also note that, as Coby points out, half is accumulating snow but the other half is losing ice. There is currently a net loss of ice.

There isnt global cooling? Since 1998 the USA has cooled by 0.78F and yes i know that is only the USA but this type of cooling can be seen in all parts of the world. So therefore the planet is cooling no matter what type of spin you put on it.

My reference to GW =GC is based on the spin doctors at the IPCC which made the claim that the Arctic sea ice is melting as expected due to GW but the Antarctic sea ice is increasing (record levels in 2007)which is also caused by GW. Which is why the name was changed from AGW to climate change,

but now we discover the Arctic sea ice levels are back where they were in 1979!!!!! so now i am very confused we know that GW causes the Antarctic to increase in sea ice extent (because the IPCC said so) but does GW cause the Arctic to increase or reduce in sea ice extent?

If you bother to reply please dont give me gobble de gook nonsense answers just straight scientific facts will suffice.

I had a look at your ever reliable GISS data and it only goes back to 1880 which is about where the warming starts. Its a shame you cant see back any further to see when the warming really started, maybe you can find a more accurate data set to show me. Also even though the planet is cooling you still say it is warming so let me ask you this. What is the level of cooling required by you to be convinced that the planet is actually cooling? ie back to 1900 temps for example? or 1940? what level do you require?

Crakar,

The Arctic sea ice extent is decreasing quite clearly - see http://scienceblogs.com/illconsidered/2008/09/arctic-sea-ice-recovered-…

Please get your facts straight before criticising others. The fact that you use the 1998 argument for cooling isn't helping your credibility either.

Let's not forget that Antarctica is ice covering land, the Arctic sea ice ice on top of water. Ice can form much easier on land because solids retain their temperature better than liquids. Based on these very simple principles it should be very easy to see why ice would stand a chance at being retained in the south pole and not the north pole. If we look at regions of Antarctica that have no landmass beneath it then we begin to see that the ice is indeed melting there.

Ice is also much more dense than snow so a three inch layer of ice does not equal (in terms of molecules of volume of water) three inches of snow.

Polar regions aside it is muchmore useful to pay attention to desertification of inland regions such as the expanding deserts of North America and the Sahara. Granted, rapid desertification is also caused by salt deposits due to irrigation, however rainfall measurments in desert regions is not effected by salt deposits. Looking above you may find it odd that I would point to lower rainfall when above it clearly says the reason for Antarctic ice growing is due to increased prcipitation. Its important to understand that the Antarctic desert is very cold year round while the inland deserts of North America and Africa are very hot. The shift in temperature in antarctica pushes it to a level where higher levels of precipitation can fall. Warmer trends in already hot reagions push the circumstances outside of a range where clouds form and precipitation falls.

Hi, if the last post is correct whey then does the Australian government believe that the reason for their latest forest fires was that the sea temperature in the adjacent Pacific was colder than usual meaning no evaporation and therefore no precipitation causing the fires to rage out of control.

[Hi David,

I am not aware of this claim being made by the Australian government. Do you have a link? Given the 12 year drought that region has experienced, it is hard to think one cooler year in the Pacific merits all the blame!

I deleted the rest of your several hundred word comment because it was off topic, rambling and unsubstantiated
- coby]

David Wells -

Accusing scientists of defrauding taxpayers and willfully misrepresenting data is a pretty serious accusation. I presume you have some evidence to back up your claims?

This is the main reason why I cannot buy into the whole GW movement. Everywhere we see claims of doom from melting Antarctic ice. Most scientists and this web site instruct us that Antarctica is not melting. But here we go on to conclude that this is somehow consistent with GW theory. So if it is melting, it supports GW, if it is not melting it also supports GW.

Further, your philosophy of looking at many indications to discern an imminent global catastrophe runs out of steam quickly when this type of logic is employed. Makes one wonder about all the other assertions.

RS,

Dont get confused between these two statements;

"Antarctic ice is melting and sea levels are rising"

and

"Antarctic ice will melt and sea levels will rise"

You see every scary story tells you what WILL happen its just not happening yet, get it?

Cheers

Crakar

OK Crakar, so whatever happens GW is supported? And everything is always future so there is no data...

R

Crakar your global cooling idea expressed above has yet more support:

http://my.auburnjournal.com/detail/108731.html

Everywhere we see claims of doom from melting Antarctic ice.

Correction: most discussion about melting and sea level rise revolves around Arctic ice, because the trend there is clearer and better understood. As Coby mentions in the post, and which you can read at other websites, the Antarctic trend is a lot more unclear, and reports that indicate ice increase tend to be localized.
Furthermore, studies show that Antarctic temperatures are increasing overall.
http://www.antarctica.ac.uk/press/press_releases/press_release.php?id=91
http://www.realclimate.org/index.php/archives/2009/01/state-of-antarcti…

Further, your philosophy of looking at many indications to discern an imminent global catastrophe runs out of steam quickly when this type of logic is employed. Makes one wonder about all the other assertions.

When you fabricate facts, look at localized effects, and misrepresent research, you can say pretty much whatever you want. I don't know if you're willfully misrepresenting the research, or are fundamentally ignorant of the actual arguments, but when you "employ this type of logic", it's very easy to take apart your arguments.

Crakar your global cooling idea expressed above has yet more support:

First sentance from that article:
"Despite no global warming in 10 years and recording setting cold in 2007-2008, ..."

Bam, right off the bat, epic fail. Article can be disregarded. Keep swinging, slugger, you'll hit one out of the park eventually.

Further correction, melting Arctic ice does not increase sea levels, it is already in the sea. My observation comes from various documentaries on GW. Specifically Gore's AIT, are you asserting that reference is not made?

As for your second comment note I did not represent any facts or research just pointed out a contradiction in the GW theory. You however, support my overall assertion that logic takes a holiday in "GW think". You misrepresent what I said and finish off with ad hominen irrelevance, without those rhetorical tools there would be no GW movement.

RS you should take 10 minutes and read the links that Adam provided. Unlike the TV weathermen at SPPI, Eric Steig is an actual climate scientist and is very good at explaining the science to the rest of us.

You mean read his when he refused to read mine?

this one might be more interesting, instead of simply playing dueling websites lets look at the way the GW theory is being advanced, mainly duplicitous assertions and cover ups, and of course endless ad hominem attacks, only Nietszche gets away with that.

http://wattsupwiththat.com/2009/01/27/james-hansens-former-nasa-supervi…

Ok so i read them. You cannot be serious about using this as supporting anything. The Steig report has already been discredited, that was fast. And little wonder, here is the description of the method from the NY Times:

"In the new study, scientists took into account satellite measurements to interpolate temperatures in the vast areas between the sparse weather stations."

read: weather stations are sparse in Antarctica so we made up the data. Among the scientists in this group was none other than Michael Mann, well known for fabricating the hockey stick graph. Very helpful inofrmation. My claim that GW theory is insidious and dishonest now has new support thanks to these citations. Have a nice day.

Gee, what a surprise, you don't like satellite data in the antarctic that indicates warming. Are you similarly wary of the satellite data that indicates tropospheric warming is less than models predict? The satellites are by far the preferred data set for the denial side of this debate.

RS -

I read the link to the article you provided, and I'll reiterate my claim; it's complete bollocks.
quoted from above:
First sentence from that article:
"Despite no global warming in 10 years and recording setting cold in 2007-2008, ..."

Bam, right off the bat, epic fail. Article can be disregarded.

Blatant disregard for basic scientific information means I don't take them seriously. Nor should you, if you're being honest.

re: that Watt's up with that post:
This again? Sigh, I'll just post what someone who actually bothered to contact Hansen said:
"John Theon never had any supervisory authority over me. "
http://bigcitylib.blogspot.com/2009/02/hansen-strikes-back-more-on-john…

And besides, people who say things like "Gore faces a much different scientific climate in 2009 than the one he faced in 2006 when his film âAn Inconvenient Truthâ was released. According to satellite data, the Earth has cooled since Goreâs film was released..." are also completely misrepresenting (or misunderstanding) the difference between weather and climate. To reiterate, for the slow: Weather is short term, Climate is long term.

The Steig report has already been discredited, that was fast.
Interpolating measurements using a separate data-set is not the same as making data up. Are you getting those claim's from Watt's Up With That? I have yet to see a post from there that isn't misleading.

Bam, most graphs will show you that 98 peaked and temps have been dropping since, so he is not that far off nor disingenuous. But you might as well stop reading, just in case you dont like what you read.

I have no problem with satellite data in the Antarctic or elsewhere. I struggle with "interpolated" satellite data when Michael Mann is doing the interpolating. He is, or should be, an embarrasetment to the GW movement but here he is again... Many real scientists are, lets say disappointed.
Here is a source for the critique

http://www.telegraph.co.uk/comment/columnists/christopherbooker/4332784…

and here is the report

http://www.nature.com/nature/journal/v457/n7228/full/nature07669.html

This web site indicates that Antartica is not melting. The bogus study concludes that parts of it have warmed almost 1 degree in fifty years, so -35 is now -34? melting? I think not.

And assuming that I accept satellite data in certain instances but not others brings me back to my original point, you made that up, it is not an argument. This happens too often with defenders of the faith.

Ah, yes! Christopher Booker, that paragon of scientific virtue and honestly. And surprise, surprise, he ends his column with that most scientific of arguments, arguing against big government and government spending!

Let's examine what else Mr. Booker considers scientific:

Intelligent Design
http://www.telegraph.co.uk/news/uknews/1495664/Christopher-Bookers-note… (Talking with Dinosaurs section, scroll down)

Second Hand Smoke doesn't cause cancer;
http://www.telegraph.co.uk/news/1556118/Christopher-Bookers-notebook.ht…

White asbestos not dangerous:
http://www.telegraph.co.uk/news/uknews/1381270/Christopher-Bookers-Note…

Seriously, if you're going to quote a journalist, at least don't insult everyone's intelligence by referencing some right-wing hack.

I read Booker's articles. Nothing to do with GW. So if you don't like the journalist's politics you do not feel compelled to address the opinion of the scientists quoted in his article? Cop out.

Harry Wanless presentation:

www.broward.org/climatechange/wanless.pdf

Great presentation by Prof. Wanless, UMiami. Good description of the sea level fluctuations without anthropogenic (sic) influence.

120,000 years ago at 20 feet ABOVE present sea level, then 360 BELOW our present SL just 18,000 years ago, to just 3 feet below our present level just 3000 years ago. All that without human influence.

Prof Wanless is an adamant supporter of AGW. I can't understand why when his own presentation refutes it as man made.

I guess Ford has been around longer than I had recalled.

That GW "might" be occuring has nothing to do with humans, but 99% to do with nature.

brecman,

Please see this article:
http://scienceblogs.com/illconsidered/2006/01/climate-is-always-changin…

Yes, the climate has changed for various other reasons before, that says precisely nothing about what is the cause today.

IMHO the cooling effect in Antarctica can be attributed to two causes:
1. The the depleted Ozone layer lets more heat escape causing higher atmospheric layers to become cooler which leads to stronger winds around Antarctica which leads to
2. a better isolation from warmer ocean currents.

However as the Ozone layer is regenerating that effect (however small it is) will diminish. And secondly the effect is not strong enough to compensate for a 2 degree Celsius change and of course this only means that those warm ocean currents will remain warmer and El Niño years will become more frequent.

coby: I commend you for being an AGW supporter that actually debates openly and honestly on your site.

The "Antarctic Ice is Growing" argument is rarely mentioned by serious skeptics unless as a counter the warmies who constantly use Melting Arctic Ice caps in their talking points.

"Melting Ice Caps" along with pictures of polar bears "stranded" on little slabs of ice floating in the ocean is part and parcel of warmie propaganda. That's what makes the growth of antarctic ice caps such an inconvenient truth.

"That's what makes the growth of antarctic ice caps such an inconvenient truth." - Z.

The fact that your statement is utter bollocks makes it inconvenient. The sea ice has increased in Antarctica, but the land ice is fast disappearing. We now have some evidence (although the margin of error is large) that the East Antarctic is losing ice mass.

http://www.nature.com/ngeo/journal/v2/n12/abs/ngeo694.html

"In agreement with an independent earlier assessment4, we estimate a total loss of 19077 Gt yr-1, with 13226 Gt yr-1 coming from West Antarctica. However, in contrast with previous GRACE estimates, our data suggest that East Antarctica is losing mass, mostly in coastal regions, at a rate of -5752 Gt yr-1, apparently caused by increased ice loss since the year 2006."

Copy/paste error in #35 supposed to be:

"In agreement with an independent earlier assessment4, we estimate a total loss of 190 (plus or minus 77 Gt yr-1), with 132 (plus or minus 26 Gt yr-1) coming from West Antarctica. However, in contrast with previous GRACE estimates, our data suggest that East Antarctica is losing mass, mostly in coastal regions, at a rate of -57 (plus or minus 52 Gt yr-1), apparently caused by increased ice loss since the year 2006."

I'm confused. What is the official warmie stand?

1. The growing or shrinking of Arctic / Antarctic ice IS evidence of for / against AGW.

2. These ice levels are largely irrelevant.

Sorry, forgot the 3rd choice:

3. If any ice is receding, it is evidence for AGW. If the ice growing, that's also evidence for AWG.

There isn't a "stand", Z.

Your simplistic reduction of it into a "heads-I-win-tails-you-lose" caricature shows you don't get what's being said here.

Go back and read the posts. If you don't get *them*, ask. You're trying to get away with asking, "So, which idiotic and self-contradicting version of the story do you fall for?"

Hey Z, Have you stopped beating your wife?

Skip

OK - I'll admit it. I don't get it. Help the slow kid out:

Is the growth or shrinkage of polar ice relevant to the AGW debate?

And if you find that to be a wife beater question, what exactly is the false or questionable presupposition?

"I'm confused." - Z.

Yes, quite obvious.

"Is the growth or shrinkage of polar ice relevant to the AGW debate?" - Z.

Yes.

Have a look at Google Earth Z. Note the Arctic and Antarctica. Do you see the clear geographical difference between the two?. This realization, should it come to you, might help you understand why warming is causing the polar regions to behave in a similar but not identical fashion.

Further to DW's quote above: "clear geographical difference between the two" doesn't just refer to where they are on the planet.

Great so it's relevant.

Now let's take each of the 4 possible scenarios and match them as evidence that either supports or refutes AGW.

1. Antarctic Ice Growing?

2. Antarctic Ice Shrinking?

3. Arctic Ice Growing?

4. Arctic Ice Shrinking?

Again, if this is a wife beater, please tell me the false or questionable presupposition.

Sorry, I forgot the other 2 scenarios:

5. Antarctic ice is unchanged?

6. Arctic ice is unchanged?

Again - would the above serve as evidence that supports or refutes AGW.

Thanks in advance for your help.

The question scientists ask is more like:

Does what's happening in the Antarctic match model predictions?

The answer is "yes, quite closely, except it appears to be warming a bit more than predicted". Scientists take this as evidence that the models are doing a pretty good job and are, if anything, underestimating warming in the Antarctic.

z,

The modern instrumental (direct temperature measurements) record is clear. We are currently warming at something like 0.2C/decade. Maybe a hair less. The attribution of this to various forcings, including (also directly measured) increasing CO2 concentrations is based on very solid physics. I understand that recent work has implied slightly more forcing from carbon black and slightly less from CO2, but only a small adjustment. And the isotopic signature clearly indicates the increased CO2 is from fossil sources - i.e. us burning fossil fuels.

But ice (sea and land) is not necessarily a direct response to one thing - temperature. For ice, we need computationally intense models - General Circulation Models.

Those models are based on actual physics, they aren't just some curve fitted to points. If we take what we know of conditions at some start point, say the beginning or middle of the 20th century, and run a GCM, with the *known* historic emissions of various aerosols and gases, both from human and other (e.g. volcanic) sources, we can compare the model performance against the instrumental temperature record up to the present. That is called backcasting. The most modern models, taking into account dozens of physical phenomena, at the finest spatial and temporal resolution our best supercomputers allow, do a really good job of backcasting. Therefore, running those models into the future with various likely estimates of future emissions is the best way to get a handle on what will happen to the cryosphere (icy places).

Those models have tended to predict the following:
1. Decline in arctic sea ice.
2. Increase in central ice on Greenland, decreases around the edges, with net loss.
3. Steady or increasing antarctic sea ice for maybe another 40 years, then a switch to decline.
4. Decreasing ice on the antarctic peninsula
5. Decreasing ice in West Antarctica, with a pattern kinda like Greenland (thinning at the edges, possible buildup inland)
6. Slight increase in East Antarctic ice, maybe for several decades before switching to loss.

If you run these models out to 2100 and beyond, assuming anywhere from human "business as usual" to "implementation of all emission cuts currently proposed" by 2100 all the ice is in significant decline (indeed by that time, arctic sea ice is only seasonal, like 10 months of year.) If we are dumb enough to let temperatures go up 4C and stay there for a few centuries, all of Greenland melts and so does West Antarctica. That's over 40 feet of global sea rise. Yes, probably over 5 centuries or longer, but still a very bad thing.

Now here's the worse news. I said the models are good. They are good - they predicted stratospheric cooling at the same time as ground level warming, and they were right. But, as some others have pointed out, with the exception of antarctic sea ice, all the other predictions appear to be happening faster than the models predict. Like the models were forecasting a summer arctic sea ice minimum of zero by shortly before 2100. Empirically it's looking like 2050 is more likely. The models say East Antarctica should not yet be losing volume, but satellite measurements say it is. So the models may be good, but they aren't perfect, and it appears they err on the side of "less alarming than reality".

So, does that answer your questions about ice? You seem to be asking "Is there anything the ice could do in an observable timescale that would throw doubt on global warming?" One answer would be that if the actual measured temperatures keep going up, that *is* global warming, regardless of what ice does on timescales of a few years.

But I'll throw you a bone. Two even. If five years from now the mass of the Greenland ice sheet is 500 Gt greater than today, and there isn't some obvious cooling source like some big volcanoes, then there's something wrong with the models. (Since 2000, the ice sheet has lost about 1500 Gt - see http://www.sciencedaily.com/releases/2009/11/091112141311.htm ) Similarly if five years from now the arctic sea ice minimum is 6.5 M sq km or more (with the same caveat about volcanoes) then we have a significant lack of understanding regarding sea currents and polar amplification. (for scale, back in the 80s, that number was often over 7.5. The last time it was over 6.5 was 2001. This year it was under 5.5 and in the exceptional 2007, it was under 4.5.)

Z:

These are perfectly fair questions, and I have always acknowledged this as one of the things that would light up my suspicions if I were a denier. The explanations for (sub-regional) Arctic ice growth from the AGW vantage would look to the uneducated eye as "Heads-I-win-tails-you-lose" game-rigging by AGW proponents.

But remember this, Omega-man: If its true *its still true.* You can easily throw up your hands and say, "Ah, see! No matter what happens they'll say its consistent with AGW."

But if AGW is true, then *of course* everything that happens will be consistent with AGW--the only question is how to explain it based on our current level of understanding.

I don't have the command of the models literature GFW does, but unless he's shamelessly lying, then it sounds like climate scientists have considered this issue and resolved it with the best data/explanatory models they have.

Don't fall into the linearity fallacy--assuming that *all* ice must melt, *all* glaciers retreat, *both* poles shrink, if AGW is true.

Skip

GFW,

Can you please supply a link to the model predictions you state.

TIA

Crakar24

I get the AGW theory. It does make sense . . . except for observations. But let's not threadjack and leave this about the ice.

"The most modern models, taking into account dozens of physical phenomena, at the finest spatial and temporal resolution our best supercomputers allow, do a really good job of backcasting."

I'd love to see those models too. Where's the source code for those?

[Here is one: http://www.giss.nasa.gov/tools/modelE/ -coby]

"But if [we believe] AGW is true, then *of course* everything that happens will be consistent with AGW--the only question [to us] is how to explain it based on our current level of understanding."

That is not science. That is what churches have done throughout history.

In the parent article we have:

"any argument that tries to use a regional phenomenon to disprove a global trend is simply dead in the water."

But a regional phenomenon can be used to prove a global trend?

Not even a clever twist of my words, Z.

Example of the theory of evolution. Evolutionists were puzzled by the problem of the Earth's age. How could an earth only a few dozen million years old (as geologists assumed it might only be based on the remnant of core heat) have provided enough time for the diversity of life to evolve? Even Lord Kelvin--a devout Christian and an otherwise brilliant scientist--thought this to be the ace in the hole against evolution. (This is the analog of your Anarctic Ice is growing puzzle: "If the Earth is warming, then why is (some) Anarctic ice growing? Heat melts ice, right? Therefore the warming theory is wrong! Ha!")

The solution to the problem of the Earth's age/core heat lay in the inchoate field of atomic physics. Radioactivity accounted for the persistent heat of the earth's core. Evolutionists did not fully understand this at the time they developed their theory, but it all made sense later as science progressed.

The same is true with global warming: We have overwhelming evidence of it (even most "skeptics" don't deny this fundamental fact--only whether its anthropogenic or dangerous), but we also have some puzzles that at first blush seem to contradict it (slight temperature reduction since 1998, ice expansion in the Anarctic, some glacial advancement). But the fundamental science is not threatened by this. Numerous explanations have been provided but the most basic is that natural processes are not linear. (See Jack Savage's misunderstanding of this on his most recent post.)

If you cannot see the analogy you have my sympathy but don't replace it by twisting my words.

No one says a "regional phenomenon" proves a global trend. This is a straw man. What AGW proponents do say is that when you see overwhelming evidence in *multiple* regions of a trend then yes, it is global.

Skip

Those skeptics who said that "an earth only a few dozen million years old could not possibly have provided enough time for the diversity of life to evolve" were right.

Those whose evolution theory said a few dozen million years was enough time to develop the diversity of life we have on earth were clearly wrong. It took more than 3 billion years.

I should clarify a few things
1. I'm not a climate modeler, I'm just a guy with a PhD in Physics who spends too much time reading climate blogs. I only read primary literature if it's directly linked.
2. Any error in recollection or representation of what I've read about the models is my own, and not reflective on the climate modeling community.
3. I got a term wrong. Testing a model using known past forcings against known past temperatures is "hindcasting". "Backcasting" appears to be what the deniers call it when they want to denigrate it. My mistake.

Ok, moving on. RC has an excellent compendium of the raw data, processed data, model source code, etc. at the following link http://www.realclimate.org/index.php/data-sources/

The links therein are strong on vast tables of data, and weak on easy-to-digest pictures. Such is life.

The most accessible discussion of hindcasting I've seen is at http://www.skepticalscience.com/climate-models.htm - the easy-to-digest picture there is what I'd call a good fit.

The same site has a good discussion of Antarctic land ice vs Antarctic sea ice and the current understanding of physical reasons for the sea ice increase. No direct reference to including those physical processes in models, but I'm certain I've read that some models include the ozone hole and consequent increase in circumpolar wind velocity.

My claim that arctic ice loss is faster than predicted ... also there http://www.skepticalscience.com/Arctic-sea-ice-melt-natural-or-man-made…

Note that those posts themselves generally reference primary literature, such as http://www.agu.org/pubs/crossref/2007/2007GL029703.shtml

I'm not going to walk through each and every thing I said and retrace my footsteps to the blog I got it from, and then to the primary literature they reference. I just did that one to show it can be done. If there's one I'm shaky on, it's how long the Antarctic sea ice can continue to grow before the ocean warming trend overwhelms other effects. But it only makes physical sense - under business-as-usual, or modest emission reduction, sea and air temperatures will continue going up. At some point that will dominate other effects, much like an El-Nino year in the 1980s is colder than a La-Nina year in the 2000s (global avg temps, not the local equatorial pacific surface water temps - for those, the ENSO swing is still larger).

P.S. Am I putting on airs about my degree? Meh, I might be if I told you from what University I earned it. But I left academics for a more secure (and larger) paycheck in business (aside - which by itself should tell you something about the silly argument that AGW is a way for scientists to enrich themselves on great piles of grant money). I will say that as a student, I was generally regarded as having "good physical intuition", which is physics professor speak for "accurate scientific bullshit detector".

Yeah, Z.

That's *my* point.

Skip

Z:

I have to apologize. I misread your point--and unlike your first response it *was* a clever twist of my meaning. I salute the creativity because I assume it was done in earnest.

A better response is as follows:

The "skeptics" of interest were the ones who said the *theory of evolution* is *wrong* based on what they they thought was a prohibitive contradiction--the earth (they thought) was too young. Lord Kelvin and his ilk were not reasoned "skeptics" merely saying, "An earth too young won't support evolution, but we're withholding judgment on whether evolution is true." They very much did not want to believe in evolution, and thought a young geologic earth was their ace. You tried to switch the discussion to different factions. You're very sly (but so am I.)

Your "skepticism" of interest here is your insistence that an (in places) expanding Anarctic ice sheet is inconsistent with global warming. You are *not* saying, "A climate with an expanding Anarctic ice sheet is inconsistent with AGW, but I'm withholding judgment on whether AGW is true."

No. You're saying:

"Melting Ice Caps" along with pictures of polar bears "stranded" on little slabs of ice floating in the ocean is part and parcel of warmie propaganda. That's what makes the growth of antarctic ice caps such an inconvenient truth.

You think it proves something, Z. Thus my analogy stands. You are very much like Lord Kelvin, thinking you have an ace to beat AGW as an inconvenient truth, but you're just flat wrong. Because it doesn't make sense to *you* (like evolution didn't make sense to Kelvin) does *not* mean it doesn't make sense at all.

Skip

z:

"The most modern models, taking into account dozens of physical phenomena, at the finest spatial and temporal resolution our best supercomputers allow, do a really good job of backcasting."

I'd love to see those models too. Where's the source code for those?

You'll find the code for one of the major ones here:
http://www.giss.nasa.gov/tools/modelE/

Linked from that page is code, archived runs, documentation and whatever eles you would desire if you were sincerely interested.

Ok, so *more* ice is global warming because of perspiration? But ...but... ice melting is a sign of global warming. So, if the ice melts it's because of global warming, if the water freezes it's global warming. No matter what the effect, it's global warming. No matter what happens, it's because of global warming.

And you people wonder why people think this climate change stuff is a bunch of hippie horseshit...

Mass balance for glaciers and ice sheets is accumulation minus melting and calving. Increased snowfall means increased accumulation. So if a temperature increase leads to an increase in snowfall but not a balancing increase in melting then it would lead to a positive mass balance (ie growth).

Similarly if a decrease in temperature caused a drop in snowfall accumulation but not a balancing reduction in melting or calving then you could have a negative mass balance (shrinking) as a result of temperatures dropping. That does not seem that hard to understand to me...

Sometimes life is complicated and intuition just is not enough. Sorry if that looks like "horseshit" to you, it really is just reality.

And the ice sliding off the LAND in the antarctic will become SEA ice just long enough to melt.

"Ice can form much easier on land "

Well, when the land is a few km above the sea level, it's going to be cold at the top there.

Any rain won't managed to have melted and will fall as snow.

“If the Earth is warming, then why is (some) Anarctic ice growing? Heat melts ice, right?"

Not really.

If you warm from -40C to -30C, you warmed 10C.

But it's still freezing cold.

Oh, and it will hold a lot more water which will fall as snow.

wow, i like your comment: its getting warmer but i die from freezing my ass in the ice. bravo, you are a true warmist. even when you die from the cold you think it was warmer.