The BBC says:
The melt loss from the White Continent is sufficient to push up global sea levels by around 0.43mm per year.
You say:
The effect on sea level would be 159/1000 or 0.159 x 3 millionths of a meter, or 0.477 millionths of meter of sea level rise per year from this.
So there is a factor of 1000 difference between you and the report by the BBC. I don’t konw who is right but part of your formula cancels out to one:
1 Gt x (1 km³/Gt)

How does ice melt in the interior of antartica? The temp never rises above freezing. Ice ‘lose’ in this context is probably due to ic sliding down to the sea not being replaced fast enough in the interior. The faster slide may be due to the past million years or so of grinding away an easier route to the sea.

[snip waayy off topic -mod]

One more thing conveniently omitted in the press release, but prominent in the abstract (http://onlinelibrary.wiley.com/doi/10.1002/2014GL060111/abstract): the error range for the east Antarctic ice loss of 3Gt/year is a whopping +/-36 Gt/year!

I think we lost 1000 somewhere half way through.

I think the mistake is here:
we are seeing about 159 billion tons/year of ice converted to meltwater (unless it sublimates), so the effect on sea level would be 159/1000 or 0.159 x 3 millionths of a meter
There’s no need to divide by 1000 as 1bn tons (tonnes?) is the same as 1GT, not 1000 times larger

The Guardian are expert at presenting any cause in the most dramatic, scary terms.
‘Collapse’.
‘Doubling’.
‘Irreversible’.
‘Shedding’.
‘Catastrophic’.
‘Sea levels to rise 4 metres’
Shedding 160 billion tonnes annually sounds suitably ‘catastrophic’. Causing sea levels to rise by a fraction of a mm each year, taking ‘up to 1,000 years to rise by 4 metres’, not so much.

Harry,
Nearly half a millimeter a year is certainly significant – though not enough to reach some of the extreme claims for sea level rise

If the “new” cryosat 2 is a much improved version of the old one, how do they “know” they weren’t under-measuring this paltry amount of ice melt in the first place, so how do they “know” it’s actually got worse? If this is raising sea-levels by c0.45mm/annum, to achieve the much ballyhooed 6m sea level rise would take well over 13,000 years to do it! To raise sea-levels by 1m would take over 2000 years to achieve!
Deja vu. At the risk of repeating myself. When in college in the 1980s, during our surveying sessions we were instructed about the all new Wilt T2 Total Station Theodolite with it’s “pretty sophisticated bit of electronic kit!” (Their words not mine). We were also advised that Wilt (pronounced Vilt) could measure angles to 1 second of arc accuracy & was the best in the World. However, being engineers, they advised us that the Japanese also claimed their top range theodolites could also read angles to 1 second of arc accuracy. The difference being, that the Japanese actually ground their optical lenses to 1 second of arc accuracy, whereas the Swiss instrument had its optical lenses ground to only 3 seconds of arc accuracy! Just saying, it’s all down to tolerances. I have seen claims for all sorts of climate related things over the last ten years, much based upon modelling, whereby temperature or sea-level or whatever could rise by ‘X’ or ‘Y’ amount per year + or – ‘2X’ or ‘2Y’ tolerance. In other words zero rise!

Is there an isostaic rebound calculation used with cryo sat2

“The radar can measure the surface height variation of ice in fine detail, allowing scientists to record changes in its volume with unprecedented accuracy.”
The so called loss of ice could be due to land subsidence. They should be measuring the surface level of the ice as well as the underlying level of bedrock to assure that there is a loss in the volume of ice. At the moment they are only measuring a gain in air space.

Joel O’Bryan says:
May 20, 2014 at 1:52 am
So, what would a gazillion measure? (Tongue planted firmly in cheek!) 😉 Probably any scary number that hasn’t yet been thought of that counteracts the facts?

Just to sum up the maths (because I had to check it anyway!)
1 Gigatonne = 1 km3
So a sea rise of 2.78 micron per 1 km3 melted is correct for the stated ocean area.
So melting 159 km3 would result in a sea rise of 441.7 microns, or 0.4417 mm……
So you are looking at 159 of those blocks …
But even that wonderfully accurate satellite does not really know what the melt rate is, because ice loss measure is complicated by isostatic rebound – as ice is lost, mantle rock moves inwards and upwards to take its place.
……and so computer models are employed. Many revisions of their outputs have occurred.
From Skeptical Science:
Previous predictions of present-day GIA have implied that this process adds 100-200 Gt/yr to the GRACE signal over Antarctica; this must be subtracted from the raw GRACE data to reveal the rate of present-day ice-mass loss. This GIA correction is about as large as, or larger than, expected present-day ice-mass change. If the GIA model were to predict smaller GIA mass change, the GRACE estimate of ice mass change would be smaller by the same amount, so it’s clearly very important to have an accurate GIA model.
To me, …. not so re-assuring that the figures are meaningful.

“ven then, trying to spot 159 blocks of ice missing in 14 million is like trying to find a gnat’s brain with a magnifying glass – impossible. In the grand scheme of things and in context the numbers are nothing. But the SOP of those with a campaign to push is to use large scary numbers.”
That will take about 88.000 years? And sea level rise of about 38 meters?
?

I always go for the so called supplementary information to the paper which is usually free and gives you the detail as to how they did their detailed calcs. Here’s the link to the supplementary pages for this paper (taken by navigating through links from the BBC article):
http://onlinelibrary.wiley.com/store/10.1002/2014GL060111/asset/supinfo/Aux_material01.doc?v=1&s=71ac88fc936c00a2f80a41a3d7570004457788e9
It’s all estimates ladeled on model outputs…ladeled on more estimates.
@Alan the Brit: you are right. They say that the increased resolution has added thinning data for the West Antarctica peninsula and other coastal regions, adding 31% of loss at a stroke and that is what brings the new measurements into line with ‘other methods. In other words, that 31% loss increase was always there and is being used as part of the “doubling”. They hurriedly go on to say but the whole sheet has thinned too but don’t say by how much (the 2cm/yr statement is a back calculation from the 160 Gt loss so isn’t the actual elevation reduction they are referring to). So we are left in the dark as to what the real world increase is over the 2005 to 2010 survey. The info in this paragraph isn’t in the supplementary pages but gleaned from various sources including the BBC article and the abstract.
Can someone here dig out the 2005-10 survey data just to check they are not spinning regarding the simple, raw data doubling as well? If they are, the resulting decrease from 2010-13 may be commensurate with the East Antarctica gains in previous years, in other words, equilibrium.
PS I realise the 31% loss on coastal regions can’t be directly compared with the 100% doubling because it is regarding a sub section of the whole sheet. However, we don’t know how big a sub section it is and the authors acknowledge that the coast is where most of the thinning is. By that logic, the phantom 31% portion of the increase in coastal yearly loss could actually translate to more than 31% of loss for the whole sheet if the elevation of the rest of the sheet is near-stable. That may be the reason they rush to say that the whole sheet is losing ice. I suspect that portion of the loss is minuscule and well inside the vast error bars cited in the abstract. If so, this would leave the phantom 31% as the prime contributor to the claimed doubling. I smell a rat.

What is the dynamic ice balance for Antarctica? it collects up say .3 meter =( .3/1000 km) of ice each year via snow etc x 14 m sq km = 4200 cubic km annually so the article is saying that the continent is loosing 4360 cukm or 3.8% more annually over the period of observation, a small increase in precipitation of 3-4 % over a period ,or a minute amount of cooling will change the ice loss to and ice accumulation. The observed change probably falls within a range of natural variability.

160 Giga tonnes sounds like a lot, but not when you know that total accretion each year is around 1900 Gt (so total loss must have been around 2060 Gt). Since accretion and loss are totally different mechanisms i find it quite surprising that there is almost as much total gain as total loss.
http://www.waisworkshop.org/presentations/2011/Session4/Zwally.pdf
Its a standard trick of AGW propagandists to quote big scary numbers, and to fail to put them in a proper perspective.

given most the population spend their school days taking selfies its easy to impress people with big sounding numbers and so make it scary.

“1.37 BILLION CUBIC KILIOMETERS. 1.37e9 cubic kilometers means nothing to most people.”
Neither does a “billion” apparently.

Fascinating that as summer fails to take hold in the Northern Hemisphere that the Warmist Alarmist machine turns to the vast, frozen and very remote continent of Antarctica as it’s major source of scare stories.
I’m beginning to think that we skeptics are the only people who take these pricks seriously any more.

http://www.leeds.ac.uk/news/article/3531/antarcticas_ice_losses_on_the_rise
It would also be good have a link to the press release at the top , not just leeds.ac.uk , saves having to go digging.
This is more spin my press release. The caption on the headline photo reads :
“Three years of observations show that the Antarctic ice sheet is now losing 159 billion tonnes of ice each year – twice as much as when it was last surveyed. ”
Which gets reported by the Guardian as “Doubling of Antarctic ice loss revealed by European satellite”
NO , the GRL article actually reports: However, the average rate of ice thinning in West Antarctica has also continued to rise, and mass losses from this sector are now31% greater than over the period 2005–2011.
The also screw up the increased ice loss and report “losing almost one third (31%) as much ice “:
But the average rate of ice thinning in West Antarctica has also increased, and this sector is now losing almost one third (31%) as much ice each year than it did during the five year period (2005-2010) prior to CryoSat-2’s launch.
DUH.

Yes mods, could we just fix the top article? The line where he divides 159/1000 just needs to have the 159/1000 removed and that and all subsequent references to 0.159 converted to 159. It won’t do to publish egregious arithmetic errors on WUWT, especially when the error favors the skeptical argument. Especially where one doesn’t need the error to make the point.
Now, what is NOT known is how long this melt rate has been occurring — quite possibly it extends all the way back to the Dalton minimum, more likely it started somewhere in the 1930’s or 1940’s when temperatures peaked from the early 20th century (non-CO_2-linked) warming from 1910 to 1940, with some fluctuation over time. That is, we really do not know how much of the baseline SLR over the last 145 years of the tidal gauge record (useful or useless as it might be) is due to ice melt over that entire period vs the amount due to expansion. It is quite plausible that of the current 3 to 3.5 mm/year rise, 0.5 mm/year comes from melting ice — that’s the scale that would knock the rate back down much closer to the 145 year average. OTOH, some fraction of that 145 year average might have come from ice melt too. In ten or twenty years of observations, perhaps we’ll know.
In the meantime, antarctic sea ice is at record levels of coverage, which actively increases the albedo of the southern pole and provides a form of negative feedback. I have no idea what (if any) effect it has on southern hemisphere cloudiness and hence further feedback both positive and negative.
Finally, I do not think that this word “irreversible” means what you think it means…
rgb

” Espen says: @ May 20, 2014 at 1:20 am
One more thing conveniently omitted in the press release, but prominent in the abstract (http://onlinelibrary.wiley.com/doi/10.1002/2014GL060111/abstract): the error range for the east Antarctic ice loss of 3Gt/year is a whopping +/-36 Gt/year!”
Indeed, the errors are 50% of the estimated loss: ” Between 2010 and 2013, West Antarctica, East Antarctica, and the Antarctic Peninsula changed in mass by −134 ± 27, −3 ± 36, and −23 ± 18 Gt yr−1 “.
In any event, half of a very small number is still a very small number. Be it 159 KM**3 or .159.
Good to see the WUWT readers are on their toes from the very first response. Hopefully we will see a correction soon.

“This study does a nice job of revealing the strong thinning along the Amundsen Coast, which is consistent with theory and models indicating this region is in the early stages of collapse.”
Well, that at least explains all those useless models, maybe they should take up the catwalk instead !

Sanity check required at WUWT!
– you divided by 1000 when you shouldn’t have!
It’s 0.43mm / year

As Geoff notes above:
159 gigatonnes = 159 km3.
According to Wikipedia, the Antarctic ice sheet = 26,500,000 km3
Therefore, the loss is equal to 0.0006% per year. If your satellite is accurate enough to measure that, well, that’s pretty impressive.
Time to melt at a constant pace: 170,000 years.
I am further hard-pressed to understand the mechanism of loss. Temperatures are ordinarily well below zero, with the coldest ever temperature of -135 deg C recorded in Antarctica just this past December. Surface temperatures should have minimal effect on temperatures at the base of the glaciers.
I would add that annual precipitation is reported as 166 mm per year, representing a volume of 23 Gt over the continent as a whole.

Glad to hear one of my clan has found employment.
The warmist arithmetic is correct at around positive 0.45 mm/year. That is slightly larger than the estimated ±0.4 mm/yr uncertainty in the GMSL estimate, but the applied glacial isostatic adjustment is a negative 0.3 mm/yr, so we’re back within the uncertainty range.
So, relocate the penguins to Barrow?

I like how on one of these models which calculate 900 years for total west side glacier melt/collapse/catastrophe the climate scientist makes the remark: think likely the collapse could happen within 200 years. Like why not model that? seriously what good is spending all that time crunching data things that make 900 years if 200 years is better…You could just say THAT…Like…yeAh

The 159 (American) billion tons of ice per year does worry me because the overall temperature isn’t increasing much, this tells me the ice loss is probably caused by ice falling off the edges. This could accelerate and if we are unlucky it could lead to a much faster sea level rise, say 1 mm per year. This turns out to be 1cm per 10 years, or almost 9 cm by the end of the century. If I were to add the sea level rise caused by water expansion I get as much as 60 cm. This tells me we need to focus on geoengineering to cool the planet because I don’t see much action to stop growing rice, raising cattle, making cement and burning fossil fuels.

As long as this happens i am not going to worry,
Halley VI[edit]
It is a structure which, like Halley V, is jacked up on legs to keep it above the accumulation of snow. Unlike Halley V, there are skis on the bottom of these legs which allows the building to be relocated periodically.

Not accounting for sublimation effects makes any conclusions about sea level rise a bit pointless. A dryer antarctic climate in recent years would produce the same effect without any effect on sea level rise. Without some method of tracking precipitation changes along with the altitude data and combined with sublimation rates, this paper is leaving a lot of independent variables out.
Of course the double check on all this is the rate of sea level rise, which the raw data seems to show is slowing down, not accelerating.

Once the math is sorted to everyone’s satisfaction, might I ask that somebody take note of what Greg said earlier – these numbers are too big to have any meaning for the average man in the street (me). So for example, it might make more sense if the simplified math was along the lines of . . man worth £2.7 million is losing (say) £1.59 or £159 per year. Or perhaps, imagine a block of ice the size of a standard 6ft tall fridge freezer – then say it’s lost the equivalent of a couple of ice cubes. Would do it myself but as you can tell, I’d likely get it wrong!

Thanks to satellites and computers we can now accurately measure the number of tress in the forest, in the past we had to use our fingers and observation. Has there less tress in the former than the latter this proves we are running out of trees.
Anyone spot the problem with that idea , while you cannot take a very accurate measurement from now and compare it with very inaccurate measurement form the past and claim it shows a trend . For you no idea at all what the numbers in the past would have been if you had the accurate measurement has opposed to the inaccurate one.
and that is before you get to if the reducation is actual meaningful.

It is a trivial rate of rise because it is a trivial increase in volume. http://apod.nasa.gov/apod/ap120515.html

Not to nitpick, but two edits still need to be made:
1) Now that the figure for total Antarctic land-ice loss is 169,811 years instead of ~169 million years, the statement “I’m pretty sure we’ll have gone through a few ice ages by then.” should be changed. Perhaps to something like “I’m pretty sure we’ll have gone through an ice age by then.” ?
2) The strike-through in the statement “So, the ice loss per year would be 0.159 cubic kilometers.” includes all the digits. Strike only the zero & decimal point instead, leaving ‘159’.

“If a chunk of ice the size of Manhattan breaks off of a glacier, the worldwide media wrings its collective hands. But if sea-ice coverage grows by the size of seven states plus 184 Manhattans, you hear nary a word”
Robert Felix.

159 billion tons of ice. Is this not the amount that surrounded Chris Turney’s expedition last year. How ironic.

Does anyone know what’s happening with the earth’s tilt at the moment.

An additional sanity check. A 1mm rise in sea level will create approximately a 4mm inland shift of the ocean, producing an increase in oceanic surface area of an order of magnitude when it comes to evaporation and redeposition of that moisture as snow.

SIGINT EX says:
May 20, 2014 at 10:01 am
Neither the press release nor the authors would like to discuss the +/- 2.6 cm radial error and the -58.6 cm bias.
http://www.dgfi.badw.de/index.php?id=379
“The Cryosat-2 data for the three different measurement modes (LRM, SAR, and SARin) are combined within one GDR product which is globally available. Nevertheless, up to now, there are still some known problems with the SAR and the SARin data part in the Level 2 product and actually, only L2 LRM data should be used. The global mean range bias of this data set has been computed to -0.586 m. A timing error of about 11 ms is still present in the data. With 2.6 cm RMS of the radial errors the data quality of Cryosat-2 is very promising but not yet comparable to Jason and Envisat missions.”
The Antarctic Ice Sheet is roughly 14,000,000 km2 in area. In order to detect 159km3 of ice loss, by my reckoning, you would need to be able to distinguish 159km3/14Mkm2 = .000011m or 11microns.
Once again we have a bunch of clever dicks given lovely pieces of high priced government sponsored technology to play with and descending into metrological delusions of grandeur.
It doesn’t take any high degree of technical knowledge to demonstrate to impossibility of these accuracy claims. We are dealing here with measurements of height. To measure a height, once or over time, you need a fixed reference frame, but over any time span of the last 40 yrs there is nothing in the entire system of the Earth, including especially all those lovely orbiting devices, whose positional (x,y,z) has been fixed and known for any time segment of that era.
For all of these number crunchers this stuff is their live’s work. They go in every day and diligently try to make chicken soup out of chicken shit. I think they should be forgiven for pretending to themselves that what they have accomplished is in fact meaningful, but the rest of us are under no obligation to support them in their delusions.

Robert Brown says:
May 20, 2014 at 5:00 am
…
In the meantime, antarctic sea ice is at record levels of coverage, which actively increases the albedo of the southern pole and provides a form of negative feedback. I have no idea what (if any) effect it has on southern hemisphere cloudiness and hence further feedback both positive and negative.
I would have thought that increasing Antarctic sea ice leading to increased albedo would be a positive, not negative feedback, since increased albedo causes cooling, which would be expected to lead to more sea ice, etc. Note RACooke’s frequent posts on the subject of Antarctic albedo (more significant than Arctic due to lower latitude of sea ice thus more reflection).
I do realise that over the Antarctic land mass albedo from surface snow is anomalously higher than that from cloud, since the snow presents such a pure white surface. However this is probably not the case for sea ice whose surface is more irregular and cracked with patches of dark sea in between.

PS
He even calculated difference in densities of water and ice. GOOD JOB

OK. Really dumb question. Ice loss here , ice loss there, … All very scary oooooo ahh… BUT. What is going on with Ice Gains? I figure glaciers recede with a good melting , and, glaciers advance (then calve) with a good freeze and abundant upstream snowfalls. Land ice. THEN there is what happens with sea ice. With sea ice reaching norms at the Arctic and sea ice extending into the ocean at record extents currently….SO what is going on, net ice loss? Ice Gain….?? Or , heaven forbid… stubborn equilibrium?

I like the assumption in that scaremongering that the loss is permanent.
That is, the ice which has fallen into the sea is not at all replaced. No,
never. Once in the ocean, that’s where it stays. It leaves the reader with
the image of an ever more naked, bare-rock, ice-free Antarctic. Oh woe!
Oh tragedy! The poor penguins! No more ice ramps to slide down! No
more ice shelves to provide escape from predators.
And the Antarctic peninsular, we are told, is losing ice even faster. Was
there any mention of those active volcanoes, discovered under the ice
cap earlier this year? Could they be contributing to this increased loss?
No mention is made of the year on year increasing sea-ice coverage, so I
won’t mention it either.

Oh, good. i was just about to panic, but now I don’t need to bother. Win!

steve mcdonald says:
May 20, 2014 at 10:29 am
“Does anyone know what’s happening with the earth’s tilt at the moment.”
Current obliquity is approx 23.5 degrees and reducing. The range is 21.5 degrees to 24.5 degrees with a periodicity of 41,000 years. It takes approx 6833 years to change 1 degree so in 4819 BCE Earth was at max obliquity. In 15680 CE Earth will be at min obliquity.
Keep in mind that current precession has Southern Hemisphere summer solstice at perihelion
————————————————————————————————————————-
From the text:
“this sector is now losing almost one third (31%) as much ice each year than it did during the five year period (2005-2010) prior to CryoSat-2′s launch.”
Now how do they know that?
Are they sure that the ice loss was about the same but they just couldn’t measure it accurately enough?
Because they say this:
“The radar can measure the surface height variation of ice in fine detail, allowing scientists to record changes in its volume with unprecedented accuracy.”
and this:
“Professor Andrew Shepherd, also of the University of Leeds, who led the study, said: “Thanks to its novel instrument design and to its near-polar orbit, CryoSat allows us to survey coastal and high-latitude regions of Antarctica that were beyond the capability of past altimeter missions.”

” …its glaciers may have passed a point of irreversible retreat.”
Really ? So how did it build up high enough to get higher than the point of no return in the first place then ?
Even the most optimistic pundits reckon the next glaciation will be with us in about 15,000 years, most pundits think it will be with us much sooner than that or that indeed, we have been slowly sliding into it for the last 2,000 years with a just a few short thousand years before we have to abandon parts of the Northern hemisphere.
So unfortunately for the warmists the Antarctic is melting about a hundred times too slowly.
The climate alarmists are quite happy to induce panicky headlines in the Guardian and other gullible media because then they can keep those multi million dollar research grants coming in.

meanwhile, sea levels have not risen since mid 2012

Here is the IPCC.

http://www.climatechange2013.org/images/report/WG1AR5_SPM_FINAL.pdf
Over the last two decades, the Greenland and Antarctic ice sheets have been losing mass,
glaciers have continued to shrink almost worldwide, and Arctic sea ice and Northern
Hemisphere spring snow cover have continued to decrease in extent (high confidence) (see
Figure SPM.3). {4.2–4.7}
It is very likely that the annual mean Antarctic sea ice extent increased at a rate in the range of 1.2 to 1.8% per decade
(range of 0.13 to 0.20 million km2 per decade) between 1979 and 2012. There is high confidence that there are strong
regional differences in this annual rate, with extent increasing in some regions and decreasing in others. {4.2}
Most models simulate a small downward trend in Antarctic sea ice extent, albeit with large
inter-model spread, in contrast to the small upward trend in observations. {9.4}
For Antarctica, large observational uncertainties
result in low confidence that anthropogenic forcings have contributed to the observed warming averaged over available stations. It is likely that there has been an anthropogenic contribution to the very substantial Arctic warming since the mid-20th century. {2.4, 10.3}
Anthropogenic influences have very likely contributed to Arctic sea ice loss since 1979. There is low confidence in the scientific understanding of the small observed increase in Antarctic sea ice extent due to the incomplete and competing scientific explanations for the causes of change and low confidence in estimates of natural internal variability in that region (see Figure SPM.6). {10.5}
Due to a low level of scientific understanding there is low confidence in
attributing the causes of the observed loss of mass from the Antarctic ice sheet over the past two decades. {4.3, 10.5}
In the Antarctic, a decrease in sea ice extent and volume is projected with low confidence for the end of the 21st century
as global mean surface temperature rises. {12.4}

Is there any CREDIBLE EVIDENCE for an acceleration in the rate of global mean sea level rise. I have seen many abstracts. Some say yes, some say no, some say a deceleration!!! What is going on? If the Climastrologists are right then there should be clear evidence of an acceleration. [Melting glaciers, thermal expansion, Antarctic terminal meltdown, Greenland grasslands now.]’
After all the hot and recent global warming the results are in. We are doomed to accelerdeceleration.

American Meteorological Society – Volume 26, Issue 13 (July 2013)
Abstract
Twentieth-Century Global-Mean Sea Level Rise: Is the Whole Greater than the Sum of the Parts?
………..The reconstructions account for the observation that the rate of GMSLR was not much larger during the last 50 years than during the twentieth century as a whole, despite the increasing anthropogenic forcing. Semiempirical methods for projecting GMSLR depend on the existence of a relationship between global climate change and the rate of GMSLR, but the implication of the authors’ closure of the budget is that such a relationship is weak or absent during the twentieth century.
http://dx.doi.org/10.1175/JCLI-D-12-00319.1
Abstract – 2011
It is essential that investigations continue to address why this worldwide-temperature increase has not produced acceleration of global sea level over the past 100 years, and indeed why global sea level has possibly decelerated for at least the last 80 years.
http://www.jcronline.org/doi/abs/10.2112/JCOASTRES-D-10-00157.1

Where is the credible evidence for an acceleration of the rate of sea level rise? You can’t scream ‘MELT’ for 2 decades and cannot show me the evidence.

Does Antarctic sea Ice increase when it gets colder? Surely not. When it get cold it’s actually warm and when it gets warm it’s warm. Get it?

Abstract – Qi Shu et. al. – July 2011
Sea ice trends in the Antarctic and their relationship to surface air temperature during 1979–2009
“Surface air temperature (SAT) from four reanalysis/analysis datasets are analyzed and compared with the observed SAT from 11 stations in the Antarctic……Antarctic SIC trends agree well with the local SAT trends in the most Antarctic regions. That is, Antarctic SIC and SAT show an inverse relationship: a cooling (warming) SAT trend is associated with an upward (downward) SIC trend.”
http://www.aoml.noaa.gov/phod/docs/Shu_etal_2012.pdf
http://link.springer.com/article/10.1007%2Fs00382-011-1143-9

“In West Antarctica, ice thinning has been detected in areas that were poorly surveyed by past satellite altimeter missions”.
Hmm! So they find ice is thinning in the very parts of Antarctica that they don’t know much about anyhow as it was poorly surveyed by past satellite missions.
Conclusion; We haven’t any real idea whether the ice is thinning or not because we haven’t much of an idea on what was there or what was happening to the ice there previously but it makes for a nice alarmist paper and keeps our funding going..
Urgent! Send more money!

Are they furnishing the temperature data that is making this meltdown happen?
Is anyone asking for the temperature records at the melting sites for this period of time? Is this melting ice or ice breaking off from the expanding ice shelf? Some basic info would be appreciated.

chuck says:
May 20, 2014 at 4:01 pm
“Perihelion is approximately January 3rd/4th. This is 14 days after the solstice. Around the year 1250 the solstice and perihelion occurred at the same time. ”
Yes, I should have said “near” not “at”. Was just making the point that Earth is closest to the Sun during SH summer.

SIGINT EX says:
May 20, 2014 at 10:01 am
I see from your first link that DGFI likes to ‘further improve’ the ‘data’ with models!
To further improve the data, the use of external orbits (e.g. from ESOC) as well as the utilization of a hybrid sea state bias model (e.g. provided by Altimetrics) is recommended.
Sounds like climate science.

Igor Karlić says:
May 20, 2014 at 11:45 am
1 Gt = 1 km3 of ice

This guy says this:

= the mass of 1 cubic kilometer of fresh water
= the mass of 1.091 cubic km of ice
= the mass of 0.240 cubic miles of fresh water
= the mass of 0.262 cubic miles of ice

Who’s right?

robroy says:
May 20, 2014 at 4:50 pm
“Relax alarmists, both East Antarctica and Greenland have accumulation rates that have increased over the past two decades”
…
However, “accumulation” without melt and calving rates does not give you net gain or loss numbers.

47 mm/century sea rise may be an overestimate. Most of the melting land ice is submerged in Amundsen sea. Like sea ice, it will not contribute to sea level rise. It may even lower sea level because water has higher density (lower volume per mass) than ice. Imagine a glass made of ice with water in it. If the ice submerged in water melts, will the water level rise or fall?

Uhhhh, AlGoreEffect, my friend — what the hell did you just say?
Oh, well, vive la difference, I guess. (In case the joke has simply gone over my head, let me just express my embarrassment in advance.)

I do realise that over the Antarctic land mass albedo from surface snow is anomalously higher than that from cloud, since the snow presents such a pure white surface. However this is probably not the case for sea ice whose surface is more irregular and cracked with patches of dark sea in between.
The trouble is that water vapor is literally a two-edged sword. As vapor, it is the strongest greenhouse gas in the atmosphere by (IIRC) around an order of magnitude, so increasing water vapor can and does measurably increase the GHE — a lot, when considering dry air versus saturated air. In arid deserts, temperatures skyrocket during the day and plummet at night because of the absence of a water vapor driven GHE — CO_2 alone isn’t nearly enough to keep upward facing surfaces from rapidly losing their heat due to radiation. In very humid tropical climates, the nights are consistently warm because of the GHE.
However, water vapor is also the mediating agent for two major cooling mechanisms. One is the bulk transport of latent heat — sunlight and LWIR hit the sea surface and cause rapid evaporation of surface molecules of water. Wind blows over the ocean surface, stripping off water molecules as it goes. This evaporated water has a huge heat content relative to liquid water — the latent heat of vaporization. As the warm water vapor is carried aloft by convection, it carries the heat along with it. It also cools as it rides the adiabatic lapse rate upward, and further cools by radiating its heat content away (some of which returns to the Earth as GHE back radiation). Eventually the partial pressure of water vapor in the moist air becomes saturated relative to the temperature and the dew point is reached, making it comparatively probable that the water vapor will recondense into water. In order to do so, though, several things have to be “just right”. The water vapor has to be able to lose the latent heat of vaporization that it picked up at the water surface when it evaporated. The future water droplets have to be able to nucleate — which is a lot more likely to occur when there are ionic aerosols in the atmosphere as water (a polar molecule) is attracted to bare charge of either sign.
Once a water droplet is nucleated and grows past a critical size (that depends weakly on humidity and temperature) its surface becomes large enough that growth due to increased surface deposition outweighs loss due to surface evaporation, and the droplet stabilizes as a single droplet of condensation in a cloud or continues to grow to fall as rain. Either way the water, now high in the troposphere and hence through most of the optically opaque greenhouse layer, releases heat that is “short circuited” through the greenhouse mechanism and lost to space via radiation.
The cloud, as you note, has a very high albedo. High albedo means that it strongly reflects short-wave (e.g. visible) radiation without ever absorbing it and being heated by it. During the day, clouds outside of the polar regions act as a cooling agent, reflecting sunlight before it has a chance to reach the ground and lower troposphere to warm either one. During the day and the night, however, the cloud also acts as a powerful greenhouse blanket, directly reflecting LWIR as well as visible back down towards the Earth’s surface. In the tropics, daytime reflection wins by a landslide — reducing the incident sunlight by a huge fraction for a large fraction of the day beats the comparatively small modulation of surface radiative losses both day and night. In the temperate zone (again, IIRC) albedo still wins, but by a smaller and smaller margin as one creeps north (and in ways that are increasingly dependent on seasonal weather patterns — in the winter clouds can easily be net warming where in the summer they can be net cooling).
However — and this is key and the reason I’m replying to you — in the polar regions clouds are generally net warming, at least most of the year. You’ve already indicated some of the reasons — the polar regions are already often or permanently ice covered, and the gain in daytime albedo from clouds vs ice is not so great. The real problem, however, is that nighttime warming from the enhanced GHE from clouds scales with the fraction of the day that it is nighttime, and of course inside the arctic circles that can be as long as 100% of it. High albedo doesn’t cool when there is no incident sunlight to reflect, and even in the arctic summer, the sun comes in at a substantial angle so that direct solar warming is weak (so that clouds can reflect only a proportionally smaller amount of heat). A lot of polar temperature is determined by heat transport, not direct heating, explaining the substantial difference in mean temperatures of the North and South poles. In the north, there is substantial heat transport and heat exchange via the ocean; in central Antarctica there is only the atmosphere to carry heat in from the warmer latitudes and it just can’t do the job half as well.
That’s why I hesitated to assign a sign to the net feedback from any sort of local modulation of e.g. ocean-air humidity or sea ice coverage. The processes are COMPLEX and can have either sign, and they are NON-LOCAL as adding humidity in one place can increase albedo someplace else thousands of miles away is it finally concentrates enough to form clouds. A large part of the rain that falls over North Carolina comes up from the Gulf of Mexico maybe 1000 miles away. Some of it comes all the way over from the Pacific, where some of that might have originated in e.g. the growing El Nino. Heat from the tropical Pacific can be transported all the way to NC before it finally releases its heat and falls as rain, before it finally creates clouds that cause NC to cool after helping to greenhouse warm much of the surface area it crossed in between.
This is the kind of thing that the models are supposedly trying to model, but they perforce replace all of the small-length scale detail of this description with presumptive averages over cells 100-300 km square (where weather phenomena such as thunderstorms are order of 1 to 10 km square, where the details of front structure and development are much finer than this). They are excruciatingly tuned to aerosol levels and albedo — they have to be to stabilize anywhere near the correct/observed temperatures and preserve the central tenet that CO_2 causes X amount of baseline warming that is on average augmented by additional water vapor.
This last assumption is finally dying a quiet and well deserved death. AFAIK, it is due to Hansen, who in his original papers predicting disaster assumed universally positive water vapor feedback (and for no particularly scientifically motivated reason that I can see, hypothesized truly absurd levels of water vapor feedback that doubled or tripled the CO_2-only warming of his then very simple models). Naturally, some of the GCMs out there have built into them parametric assumptions that preserve this much “climate sensitivity” — total ACO_2 warming plus feedback, usually at the expense of an overdriven response to e.g. volcanic aerosols necessary to explain periods of global cooling and to keep the model from having a runaway exponential instability (because one has to have a mechanism that keeps positive feedback water vapor from causing increase of water vapor without bound just from FLUCTUATIONS in water vapor content or global temperature — the climate cannot be a biased random walk where every time the temperature goes up a bit, average water vapor increases and hence resets the Earth’s average temperature a bit higher unless a competing process can completely erase the gain when the temperature fluctuates down a bit).
At the moment, estimates of climate sensitivity are struggling to retain any net positive feedback from water vapor in the face of data that already solidly excludes the kind of absurd feedback levels Hansen originally hypothesized. Even the question of net negative feedback from water vapor, long considered to be anathema in climate science (except for a few mavericks who managed to publish papers suggesting that clouds could easily lead to net negative feedback through the dual mechanism of latent heat transport and modulation of albedo) is no longer completely off of the table. I don’t know that people will start to take it too seriously unless/until the Earth actually cools (several tenths of a degree, sustained, not just vary up or down or weakly downward trend) but obviously if this happened it would truly be the only likely catastrophe associated with global warming to all of those that have invested their professional careers, hundreds of billions of dollars of global wealth, and their political and/or scientific reputation on shaky claims in poor agreement (so far) with observational data.
IF there is a super-ENSO, perhaps it will help their arguments survive a bit longer, or perhaps it will truly kick up the temperature to where the models become believable again. Perhaps not. ENSO is not the only factor in climate evolution, and while it has been dominant for the last half century or so in mediating positive jumps as documented by Bob Tisdale, its ability to do so could easily be predicated by the phases and states of the other decadal oscillations, the state of the Sun, the state of baseline vulcanism, the immediate past climate history, and the price of tea in China. A chaotic nonlinear system can be quasiperiodic and apparently causal for a while and then for no computable reason change to an entirely different mode of behavior where a significant quasiparticle/process becomes insignificant and some other process becomes the critical driver. We could still watch as the developing ENSO discharges all that heat in such a way that it never manages to raise global average temperatures by much because of some confounding wave that causes the heat to be efficiently transported up and quickly lost rather than persisting to spread out over the globe at high altitude, or by a mere modulation of the winds that causes albedo over the warm(ing) patch to be higher than expected so that the delivery of solar energy to the ocean is effectively interrupted. It’s not like we can properly predict ENSO (although we can do pretty well with forward projective hindsight once an ENSO process has started).
No matter what, I expect the next year to be highly informative. If we have a super El Nino that heats the planet by 0.3C very rapidly, that certainly makes GCMs more, not less, plausible on average as it kicks global average temperatures at least in the right direction for them not to be as egregiously wrong as they currently appear to be. If it only kicks the temperature up by 0 to 0.1 C, and that only transiently so that temperature in a year are again pretty much flat relative to 1998-2000, it is very bad news for the models. If it fizzles altogether — short-circuited, perhaps, by the downhill side of solar cycle 24 that maybe be beginning and which will proceed with poorly predictable speed and which may or may not have a competitive local effect on the climate and produces no gain at all and cycles immediately into a cooling La Nina that augments any solar cycle cooling to actually drop global average temperatures, that too will be very informative.
Personally, I won’t even place a bet. I don’t think the climate is computable, which means that I think one is basically betting on the output of a (possibly biased) random number generator. I’d rather play Mumbledy-peg for money.
rgb

An alternate view: while we hear considerably about isostatic rebound, there is also isotatic adjustment to loading. The Antarctic has been seeing steady increases in sea-ice for several years. If those were matched by increasing accumulations on the in the interior ice sheets, how rapidly would isostatic adjustment to increasing ice load result in lowering altitudes? Also, even without considering isostatic changes in the underlying rock, what effects would increasing load have on the crystalline structure of ice itself. I do know that increasing ice flow is likely to be due to loading because ice melting is correlated to retreats. Since the ice around Antarctica is advancing, if we accept increasing sea ice, then alternate hypotheses might be in order, to explain the altimeter data.

An alternate view: while we hear considerably about isostatic rebound, there is also isotatic adjustment to loading. The Antarctic has been seeing steady increases in sea-ice for several years. If those were matched by increasing accumulations on the in the interior ice sheets, how rapidly would isostatic adjustment to increasing ice load result in lowering altitudes? Also, even without considering isostatic changes in the underlying rock, what effects would increasing load have on the crystalline structure of ice itself. I do know that increasing ice flow is likely to be due to loading because ice melting is correlated to retreats. Since the ice around Antarctica is advancing, if we accept increasing sea ice, then alternate hypotheses might be in order, to explain the altimeter data
It really needs to be a mix of altimeter and gravitational data, because ice/snow mixes can compactify, shrink in height, and not lose a whit of mass. Note that the surface area of Antarctica is square kilometers, or (since 1 square kilometer has square meters) square meters. A loss of cubic meters — the assertion of the top article — is thus roughly 1 cm/year if removed from the entire continental ice sheet.
Of course, it is very unlikely that the satellite is going to be accurate to 1 cm. Very, very unlikely. Simply locating the satellite in 3 dimensions relative to the center of mass of the Earth is very likely not this accurate, and the effects of tidal forces and orbital paths over gravitational anomalies is very likely sufficient to make its absolute location in its orbit uncertain to order of meters. Bouncing radio signals through an atmosphere of variable and unknown index of refraction can introduce a further error of order meters. Even if they use extraordinary means to control these errors — both present in the usual estimates of uncertainty in position for/from e.g. GPS satellites — doesn’t seem likely to reduce the errors to less than order of tens of centimeters. And unless the measurements are correlated with same-location same-time GRACE measurements, reflection measurements of surface height (averaged over an enormous range, with rather large sources of measurement error as in hitting a hilltop on one pass and a valley on another) won’t tell you if you are measuring actual melt or sublimation or compactification. And even that won’t tell you if the actual ice is melting or sublimating (or where the water is going if it is melting) or if the subsidence is due to subsidence of the underlying land, which is surely proceeding at some rate given the enormous loading of Antarctica with kilometer-thick ice.
That is, I mostly agree with you. SLR and isostatic changes in the Earth’s rather plastic “surface” relative to some imaginary surface of perfect rotational-gravitational equilibrium is one of the most difficult chores we attempt, requiring a truly precise knowledge of gravitation, local coriolis force, and a fair bit of the dynamics of the underlying crust and mantel. It is also slow, constantly responding to stresses laid down thousands of years ago. Much of the planetary surface is still reacting to the ice melt at the start of the Holocene and the resulting substantial rearrangment of the “isostatic” mass distribution that had prevailed over the previous 90,000 years. Other parts are responding to more local changes in internal magma flow, movement of the tectonic plates. It isn’t all that implausible that part of Antarctica is melting/compressing/subsiding at some rate (with a largely unknown split). It isn’t implausible that it is mass is growing at other places, even if the surface is not changing by enough to be detectable. To put it another way, even if a comparatively small part of the continent is losing mass at 160 Gt/year and all of that mass is going into the ocean, the rest of the continent could be gaining mass at that rate and it would probably not be detectable, the rate of growth of order a centimeter a year that could be entirely eaten by compactification and subsidence of the continent to keep the surface itself nearly unchanging in some sort of “imaginary” height above the imaginary isostatic surface.
rgb

Sorry but you f[****]d it up with not being able to handle magnitudes.
[Watch your language. .mod]

To gofigure560:
Two different things. The sea ice is floating ice around the Antarctic, which started
life on land. The tremendous weight of the ice sheet pushes it outward from the
continent and into the sea. What’s being talked about in this paper is the land-bound
ice. That’s supposedly decreasing, according to this paper, by a tiny percentage
per year. The two trends are broadly consistent–a slight warming might cause the
ice to move downward from the continental interior to the sea, and out to sea, a little
faster, thus causing the growth of the are that the sea ice covers.
My real problem is the size of the various effects that they have to subtract out
to get their final, relatively tiny, number.

The water will lubricate the collapse of the East Antarctica Ice Cap into the ocean, which will exacerbate the excess reflection of solar heat into space, which will result in Snowball Earth. Sometime between 2020 and 5020 is a best guess.