There’s some blogospheric carping about his statement in the JPL press release below regarding Greenland’s ice sheets:“… their cumulative loss could raise sea level by 15 centimeters (5.9 inches) by 2050.”
Well sure, it could be, but as this recent surprise study from GISS’s neighbors at Columbia illustrates, even though we’ve had the GRACE (Gravity Recovery And Climate Experiment) satellite looking at Antarctica, and concluding there’s been ice mass loss there, we have this new study that shows ice being added from underneath due to meltwater refreeze, concluding the models to be wrong.
It goes to demonstrate that we really don’t understand ice sheet mechanics well enough yet to make accurate forecasts, though some people think we can.
Add to that, GRACE has it’s own set of problems. And at least one model conlcusion has been revised post facto because the melt data is overestimated:
The melting of the ice sheets of Greenland and West Antarctica is about twice as slow as previously thought. The study, conducted by TU Delft, SRON and the Jet Propulsion Laboratory. The scientists published their findings in the September issue of Nature Geoscience.
We have concluded that the Greenland and West Antarctica ice caps are melting at approximately half the speed originally predicted.’ The average rise in sea levels as a result of the melting ice caps is also lower.
In fact, errors from GRACE may be quite large. So take this new release from JPL and the squawking about the forecasted sea level rise with a grain of salt. But more importantly, look at what the actual sea-level data is saying, and as Willis Eschenbach points out, natures seems to be Putting the Brakes on Acceleration.
From JPL: NASA Finds Polar Ice Adding More to Rising Seas
Store Glacier, West Greenland. A new NASA funded study finds that the Greenland and Antarctic ice sheets are losing mass at an accelerating pace, three times faster than that of mountain glaciers and ice caps. Image credit: Eric Rignot, NASA JPL
PASADENA, Calif. — The Greenland and Antarctic ice sheets are losing mass at an accelerating pace, according to a new NASA-funded satellite study. The findings of the study — the longest to date of changes in polar ice sheet mass — suggest these ice sheets are overtaking ice loss from Earth’s mountain glaciers and ice caps to become the dominant contributor to global sea level rise, much sooner than model forecasts have predicted.
The nearly 20-year study reveals that in 2006, a year in which comparable results for mass loss in mountain glaciers and ice caps are available from a separate study conducted using other methods, the Greenland and Antarctic ice sheets lost a combined mass of 475 gigatonnes a year on average. That’s enough to raise global sea level by an average of 1.3 millimeters (.05 inches) a year. (A gigatonne is one billion metric tons, or more than 2.2 trillion pounds.)
The pace at which the polar ice sheets are losing mass was found to be accelerating rapidly. Each year over the course of the study, the two ice sheets lost a combined average of 36.3 gigatonnes more than they did the year before. In comparison, the 2006 study of mountain glaciers and ice caps estimated their loss at 402 gigatonnes a year on average, with a year-over-year acceleration rate three times smaller than that of the ice sheets.
“That ice sheets will dominate future sea level rise is not surprising — they hold a lot more ice mass than mountain glaciers,” said lead author Eric Rignot, jointly of NASA’s Jet Propulsion Laboratory, Pasadena, Calif., and the University of California, Irvine. “What is surprising is this increased contribution by the ice sheets is already happening. If present trends continue, sea level is likely to be significantly higher than levels projected by the United Nations Intergovernmental Panel on Climate Change in 2007. Our study helps reduce uncertainties in near-term projections of sea level rise.”
Rignot’s team combined nearly two decades (1992-2009) of monthly satellite measurements with advanced regional atmospheric climate model data to examine changes in ice sheet mass and trends in acceleration of ice loss.
The study compared two independent measurement techniques. The first characterized the difference between two sets of data: interferometric synthetic aperture radar data from European, Canadian and Japanese satellites and radio echo soundings, which were used to measure ice exiting the ice sheets; and regional atmospheric climate model data from Utrecht University, The Netherlands, used to quantify ice being added to the ice sheets. The other technique used eight years of data from the NASA/German Aerospace Center’s Gravity Recovery and Climate Experiment (Grace) satellites, which track minute changes in Earth’s gravity field due to changes in Earth’s mass distribution, including ice movement.
The team reconciled the differences between techniques and found them to be in agreement, both for total amount and rate of mass loss, over their data sets’ eight-year overlapping period. This validated the data sets, establishing a consistent record of ice mass changes since 1992.
The team found that for each year over the 18-year study, the Greenland ice sheet lost mass faster than it did the year before, by an average of 21.9 gigatonnes a year. In Antarctica, the year-over-year speedup in ice mass lost averaged 14.5 gigatonnes.
“These are two totally independent techniques, so it is a major achievement that the results agree so well,” said co-author Isabella Velicogna, also jointly with JPL and UC Irvine. “It demonstrates the tremendous progress that’s being made in estimating how much ice the ice sheets are gaining and losing, and in analyzing Grace’s time-variable gravity data.”
The authors conclude that, if current ice sheet melting rates continue for the next four decades, their cumulative loss could raise sea level by 15 centimeters (5.9 inches) by 2050. When this is added to the predicted sea level contribution of 8 centimeters (3.1 inches) from glacial ice caps and 9 centimeters (3.5 inches) from ocean thermal expansion, total sea level rise could reach 32 centimeters (12.6 inches). While this provides one indication of the potential contribution ice sheets could make to sea level in the coming century, the authors caution that considerable uncertainties remain in estimating future ice loss acceleration.
Study results are published this month in Geophysical Research Letters. Other participating institutions include the Institute for Marine and Atmospheric Research, Utrecht University, The Netherlands; and the National Center for Atmospheric Research, Boulder, Colo.
JPL developed Grace and manages the mission for NASA. The University of Texas Center for Space Research in Austin has overall mission responsibility. GeoForschungsZentrum Potsdam (GFZ), Potsdam, Germany, is responsible for German mission elements.
More on Grace is online at http://www.csr.utexas.edu/grace/ and http://grace.jpl.nasa.gov/ .
JPL is managed for NASA by the California Institute of Technology in Pasadena.
===========================================================
Here’s the paper abstract at GRL:
GEOPHYSICAL RESEARCH LETTERS, VOL. 38, L05503, 5 PP., 2011
doi:10.1029/2011GL046583
Acceleration of the contribution of the Greenland and Antarctic ice sheets to sea level rise
E. Rignot
Earth System Science, University of California, Irvine, California, USA
Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
I. Velicogna
Earth System Science, University of California, Irvine, California, USA
Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
M. R. van den Broeke
Institute for Marine and Atmospheric Research, Utrecht University, Utrecht, Netherlands
A. Monaghan
National Center for Atmospheric Research, Boulder, Colorado, USA
J. Lenaerts
Institute for Marine and Atmospheric Research, Utrecht University, Utrecht, Netherlands
Ice sheet mass balance estimates have improved substantially in recent years using a variety of techniques, over different time periods, and at various levels of spatial detail. Considerable disparity remains between these estimates due to the inherent uncertainties of each method, the lack of detailed comparison between independent estimates, and the effect of temporal modulations in ice sheet surface mass balance. Here, we present a consistent record of mass balance for the Greenland and Antarctic ice sheets over the past two decades, validated by the comparison of two independent techniques over the last 8 years: one differencing perimeter loss from net accumulation, and one using a dense time series of time-variable gravity. We find excellent agreement between the two techniques for absolute mass loss and acceleration of mass loss. In 2006, the Greenland and Antarctic ice sheets experienced a combined mass loss of 475 ± 158 Gt/yr, equivalent to 1.3 ± 0.4 mm/yr sea level rise. Notably, the acceleration in ice sheet loss over the last 18 years was 21.9 ± 1 Gt/yr2 for Greenland and 14.5 ± 2 Gt/yr2 for Antarctica, for a combined total of 36.3 ± 2 Gt/yr2. This acceleration is 3 times larger than for mountain glaciers and ice caps (12 ± 6 Gt/yr2). If this trend continues, ice sheets will be the dominant contributor to sea level rise in the 21st century.
Received 4 January 2011; accepted 2 February 2011; published 4 March 2011.
Citation: Rignot, E., I. Velicogna, M. R. van den Broeke, A. Monaghan, and J. Lenaerts (2011), Acceleration of the contribution of the Greenland and Antarctic ice sheets to sea level rise, Geophys. Res. Lett., 38, L05503, doi:10.1029/2011GL046583.
I like to look at history first. Then ask myself is it part of a natural cycle?
“The temperature and renewal of these waters indicate that they currently cause enhanced submarine melting at the glacier terminus.”
Straneo et. al.
http://www.nature.com/ngeo/journal/v3/n3/abs/ngeo764.html
—
“…the rate of warming in 1920–1930 was about 50% higher than that in 1995–2005.”
Petr Chylek et. al.
http://www.agu.org/pubs/crossref/2006/2006GL026510.shtml
—
“The annual whole ice sheet 1919–32 warming trend is 33% greater in magnitude than the 1994–2007 warming.”
Jason E. Box et. al.
http://journals.ametsoc.org/doi/abs/10.1175/2009JCLI2816.1
—
“We found that northern hemisphere temperature and Greenland temperature changed synchronously at periods of ~20 years and 40–100 years. This quasi-periodic multi-decadal temperature fluctuation persisted throughout the last millennium, and is likely to continue into the future.”
Takuro Kobashi et. al.
http://www.springerlink.com/content/n567324n1n3321h3/
—
“The warmest year in the extended Greenland temperature record is 1941, while the 1930s and 1940s are the warmest decades.”
B. M. Vinther et. al.
http://www.cru.uea.ac.uk/cru/data/greenland/vintheretal2006.pdf [pdf]
—
1937
“Particulars are given regarding the big rise of winter temperatures in Greenland and its more oceanic climate during the last fifteen years.”
http://onlinelibrary.wiley.com/doi/10.1002/qj.49706327108/abstract
—
I’m not worried either. Not long ago we were told to be very worried about Northern Hemisphere snow and cold not returning. A thing of the past if you like.
Well i sort of think that any increase in glacier mass loss should be measurable in increased sea level rise or is there a huge oceanic plug hole?
The real problem with these models is that they are demonstrably wrong. The sea rise in the last 50 years is apparently the slowest in the last 200. Therefore in spite of the claims of catastrophic ice melt, in fact the worlds ice store seems remarkably stable. The modelers are missing something. And they really look stupid. Like a weatherman that does not look outside.
250 Feet Of Ice Accumlated In Greenland Between 1942 And 1992
On July 15, 1942, a flight of six P-38s and two B-17 bombers, with a total of 25 crew members on board, took off from Presque Isle Air Base in Maine headed for the U.K. What followed was a harrowing and life-threatening landing of the entire squadron on a remote ice cap in Greenland. (See photo of downed P-38 from the “Lost Squadron.”) Miraculously, none of the crew was lost and they were all rescued and returned safely home after spending several days on the desolate ice.
Fifty years later a small group of aviation enthusiasts decided to locate that squadron, who had come to be known as “The Lost Squadron,” and to recover one of the lost P-38s. It turned out to be no easy task, as the planes had been buried under 25 stories of ice and drifted over a mile from their original location.
http://p38assn.org/glacier-girl.htm
We seem to be someplace toward the end or at least a rather minimalist phase of this latest transgressive sedimentary phase. Natural, normal and one of those, just the way it is things in nature.
Bad news: we will need hip waders
Good news. No need to get them for about 70,000 years.
Total ice volume is about 33,000,000 km3. At a melt of 475 per year, its nearly 70,000 years.
I am instantly suspicious of any conclusion drawn from the GRACE experiment. Attempting to measure truly minute variations in Earth’s gravity field from space is pushing the limits of noise/signal.
More to the point, gravity is a total-volumetric property, so a “change” cannot be uniquely attributed to a “place” on the planet. Teasing out “conclusions” from GRACE involves horrendous corrections (satellite parameters, lunar effects, ocean and earth tides, etc., etc.) – that is, fiddling – with limited opportunity for independent cross-checks.
To me, GRACE is akin to measuring streamflow underneath a waterfall in an attempt to detect changes in a tributary stream far, far away.
A case of “Just because you can do something doesn’t mean you should”.
Watts says:
“…we have this new study that shows ice being added from underneath due to meltwater refreeze, concluding the models to be wrong……”
but isn’t that a strawman (or red herring?) So what if ice forms underneath the shelfs! The grace satellite will see the shelf floating higher whichever side the water/snow comes from, if mass balance increases, so the new study doesn’t make the models wrong (except that water is always available on the underside, but snow precipitation is limited by low humidity of frigid dry atmosphere.)
Bushy says:
March 10, 2011 at 8:19 am
Well i sort of think that any increase in glacier mass loss should be measurable in increased sea level rise or is there a huge oceanic plug hole?
Sea level may drop in 2010
Posted on January 17, 2011 by Anthony Watts
Guest post by John Kehr
“2010 could likely show a significant drop global sea level.”
“Since the data has not been updated since August it is difficult to guess more precisely,…..”
“If the drop does show up as expected it is possible that 2010 will show the largest drop in sea level ever recorded.”
“The best source of sea level data is The University of Colorado”
Has the data for 2010 since August been posted?
Is there anybody else tracking sea levels?
Do we need another Berkley’s BEST?
Notice how published “glacier” pics are always taken on sunny days, never on a cloudy or snowy one.
Another point: Is ice loss due to melting or is it due to estivation? If the latter, it shouldn’t have much of an impact of sea levels, should it?
In one of those articles on the ice mass loss, the said the ice was “leaving the Antarctic and Greenland ice sheets.”
http://sciencedude.ocregister.com/2011/03/09/uci-study-ice-sheet-melting-speeding-up/123115/
That sounds to me like ice breaking off the edges and floating away.
I know this will seem utterly trivial and of course it is but with respect (how dare I!), this does need correction because some folk may consider it’s correct usage. I am referring to “Add to that, GRACE has it’s own set of problems. ”
“It’s” always, without exception, in every case can only be an abbreviation for “It is”.
In other words, “GRACE has its own problems.”
I’m not worried in the least about sea level rise, because I know it can’t happen. I have a theory which my computer model has proven correct (even though I have no empirical evidence at all). I call it
The Hydraulic Theory.
It says simply that as the sea level rises, it pushes on the land masses much like squeezing a pimple, forcing them up from increasing pressures. We know that land is in fact malleable, and can flow in a plastic manner under certain conditions. The earth’s oceans account for more mass than exposed land, so if the water pressure is increased by a rising sea level, then the exposed land will be forced to go where there is the least resistance. Up.
This theory is beyond reproach, and I think I read it in a peer reviewed Weekly World News journal (after I had the idea first, of course).
is there a huge oceanic plug hole?
didn’t you see the last episode of “Lost?”
everyone sing along…
there’s a rock- in a hole- in a pond- in a cave- in a stream- in a jungle- on an island- in the middle of the sea…
I would have thought that The Jet Propulsion Laboratory would spend more time on, I don’t know……. jet propulsion.
The general trend of both Greenland and Antarctic continental ice, as well as most the major glaciers of the world is not in question…they are losing mass. Yes, there are minor tweeks that need to made to the general understanding of certain dynamics (such as the growth of ice from the bottom, etc.), but the trend is not in dispute. Furthermore, the fingerprints of anthropogenic warming get harder and harder to simply ignore, causing skeptics to stick their collective heads further and further into the sand:
http://www.physorg.com/news/2011-03-earth-core-climate-insights.html
Combine the shrinking year-to-year arctic sea ice, to ice mass loss in Greenland, Antarctica, and the majority (though not all) major glaciers around the world the 40% rise in CO2 since the 1700’s, and studies such as the one referenced above, and it would seem to get harder and harder to maintain a skeptics position. Reminds of the last hold-outs who doubted that smoking caused lung cancer…
“their cumulative loss could raise sea level by 15 centimeters (5.9 inches) by 2050”
And the problem is? 6 inches in 40 years. the smallest and slowest tsunami every recorded. about the same size as the male organ and similarly exaggerated.
If all of these glaciers and ice sheets are melting faster and faster…
Why has NOAA’s Climate Indicator for Glacier Mass Balance show that glacier mass balance has been growing since 2003?
Did the glaciers not get the memo from Amazing GRACE?
None of this modeling or predicting or remote sensing matters one iota. All one has to do is measure the actual trend in rising sea levels. There is no acceleration. And sea levels are supposed to be rising. We are in an interglacial and they ALWAYS rise in an interglacial. If you don’t like rising sea levels you will certainly not like the alternative–much of the Northen Hemisphere covered with a half mile thick sheet of ice! Everyone enjoy the interglacial while it lasts.
“Why has NOAA’s Climate Indicator for Glacier Mass Balance show that glacier mass balance has been growing since 2003?”
The glacial mass balance is not actually growing… The annual value is becoming less negative (recovering toward zero).
So they measured part of warm AMO cycle and extended it until 2050. Based on today’s temperature which warmed by 15°C between 6AM and 14PM, I can also estimate what temperature will be during the weekend. Just my work will not be funded by NASA.
When this scientific masturbation on the 30-year warm AMo/POD trend will come to the end?
Actually if there is a lot of refrozen ice in Antarctica it will affect GRACE results. Ordinary glacier ice is about 10% less dense than “ordinary ice” since it is created from compacted snow and contains a lot of atmospherig gases. Refrozen ice will presumably have “ordinary ice” density. This will make the gravity field over the icecap slightly stronger.
Greenland’s ice sheets:“… their cumulative loss could raise sea level by 15 centimeters (5.9 inches) by 2050.”
Assuming the recently decreasing rise rate resumes its historic satellite rate of 3.2 mm/year, that gives 12.48 centimeters by 2050. Given the error margin, 15 cm is in the ball park, but it would take a rate of 3.8 mm/year. Since my house is 90 ft above sea level, that’s 7200 years before I have a beach. We’ll be in the next ice age by then, so it’s nothing to count on.
“It goes to demonstrate that we really don’t understand ice sheet mechanics well enough yet to make accurate forecasts, though some people think we can.”
~ ~ ~
More heat in the system, ice melts, dynamics of heat distribution makes for interesting localized conditions, both in space and time. But still add heat to a virtually closed system (our planet) that was residing within a relatively steady state and we should expect boundary ice/permafrost to melts.
As is being observed.
~ ~ ~ ~ ~ ~ ~
“I’m not worried either. Not long ago we were told to be very worried about Northern Hemisphere snow and cold not returning. A thing of the past if you like.”
~ ~ ~
The Northern Hemisphere is much more than the East Coast.
Not sure how you can say “(AGW? is a) thing of the past?” What about the real Earth Observation data?
GISS Surface Temperature Analysis (GISTEMP)
http://data.giss.nasa.gov/gistemp/
~ ~ ~ ~ ~ ~ ~
“Well i sort of think that any increase in glacier mass loss should be measurable in increased sea level rise or is there a huge oceanic plug hole?”
~ ~ ~
Well they are measuring that, and yes the signal fluctuates, but the trend… trajectory is uphill.
http://sealevel.colorado.edu/
~ ~ ~ ~ ~ ~ ~
“The real problem with these models is that they are demonstrably wrong. The sea rise in the last 50 years is apparently the slowest in the last 200.”
~ ~ ~
Can you share any citation – reference?
What about the information at: “Sea Level Rise – Understanding the past – improving projections for the future”
http://www.cmar.csiro.au/sealevel/sl_hist_intro.html#fewthousand
~ ~ ~ ~ ~ ~ ~
“That sounds to me like ice breaking off the edges and floating away.”
~ ~ ~
and most the time that ice finds itself getting sucked along by currents and melting off, though not always… they do have seasons up there.
~ ~ ~ ~ ~ ~ ~
“In other words, “GRACE has its own problems.”
~ ~ ~
These “problems” you’re talking about are part and parcel of any scientific endeavor. Those kinds of “Problems” are indispensable to the learning process. Scientists are well aware of these “problems” and devote a good deal of their time delineating, understanding and quantifying these complexities.
Here check out this interesting paper: “Validation of GOCE and GOCE/GRASE Data Products, Prelaunch support …”? http://earth.esa.int/goce04/first_igw/papers/Shum_etal.pdf
What about independent lines of evidence?
Accelerating uplift in the North Atlantic region as an indicator of ice loss
http://www.nature.com/ngeo/journal/v3/n6/abs/ngeo845.html
~ ~ ~ ~ ~ ~ ~
DJ (@March 10, 2011 at 10:48 am)
Cool post. 😉
“Validation of GOCE and GOCE/GRACE Data Products, Prelaunch support …”? http://earth.esa.int/goce04/first_igw/papers/Shum_etal.pdf
Alleagra says:
March 10, 2011 at 10:37 am
Oh I dearly love a pedant: especially when it comes to punctuation.
You are of course entirely correct; it’s is an abbreviation of It is; its the objective version of his, hers or indeed ours or theirs since its can be both singular or plural according to sense. Thous is an archaic form even, I believe, in dialect.
Kindest Regards
This is more of a post than a comment, but what is written goes to the heart of these studies: that models haven’t been thought through to how they would be expressed in the real world, and so fail the evidence test, not just the falsifiability test. It comes down to this:
Houston, we have a reconciliation problem, Houston. We are missing some major new rivers.
Consider the math in the above post about icecap mass loss and sea-level rise:
1) Greenland and Antarctica: 475 gigatonnes/year, or 1.3 +/- 0.4mm /yr, increasing 36.2 gigatonnes/yr or 0.10 +/-.0055 mm/yr increase/yr
2) Icecaps and Mtn Glaciers: 402 gigatonnes/yr, or 1.10+/- 0.5(?? harder to measure losses?) mm/yr, increase 1/3X that of Greenland & Antarctic, or 0.033 +/-0.016 mm/yr
3) Thermal expansion: 90mm over 40 yrs, or 2.25 mm/yr average
[4) Additional subsurface discharge: modeled but not measurable with the huge, freshwater discharge planet wide of 1103555 mm/yr. So let’s ignore this.]
Taken together, the total contribution comes to 4.65 +/-0.9(?) mm/yr, currently, of which 45% is thermal expansion. This glacial ice melt is increasing its contribution at 0.13 mm/yr. In three years, according to the above report, we will have a sea-level rise of 5.04 mm/yr. Let’s consider that these numbers are correct and see what it means in our world as we see it, not imagine it.
It is hard to get a grip on ice melt volumes and what they must be like. For comparison purposes, let’s consider that the Mississippi River discharges a volume of 12.74Em2/sec averaged over the year. If this volume did not evaporate, the oceans would rise 1.2 mm/yr by sheer volume alone. If the water were at 0C and warmed up to the oceanic average, the Mississippi would account for 1.74 mm/yr in the planetary global sea-level rise. Although it has been hard to determine what the historic sea-level rise has been, a 21 High Quality Tidal Station study found the 100-year average prior to 1980 was 1.85 mm/yr. By that number, the Mississippi River by itself without evaporation and with heating up, could have accounted for almost all of the sea-level rise from 1880 to 1980.
Today, though, according to the above studies, the sea-level rise is 4.65 mm/yr, or 2.5 times the historical average. By 2015 it is to be 2.7X the historical average. This means that since 1980 the equivalent of an additional 1.6 Mississippi Rivers (4.65-1.85/1.74) of new water is entering the oceans and been warming up each year. By 2015, it will be an additional 1.8 Mississippi Rivers, or the equivalent of another Mississippi River plus the Ganges River relative to what was causing the seas to rise between 1880 and 1980.
In fact, if what these studies purport is true, the “operating” day rates must be greater than that. Recall that floating ice sheets do not add to sea level rise, so we can’t consider additional melting of floating ice. We can also discount that there is more floating ice than before, as they would cause the area of ice shelves next to the landmasses of Greenland and Antarctica to be greater now than before. Which they aren’t. We can also delete from consideration that glaciers are flowing into the sea and calving ‘bergs more now than in 1980 as the IPCC, the WWF et al. say that the glacial tongues are retreating up valleys and exposing new rock, not advancing and spawning a horror-show of icebergs. Moreover, if we think a solid-to-vapour sublimation and subsequent precipitation can get ice into the oceans without a visible liquid step we are stymied by the lack of increased river flow – a fact, the IPCC/ WWF proffer to warn us about a future inadequacy of freshwater. No: the only way we can get all of this proposed additional Mississippi multiple of water into the oceans is by melting the land-bound ice and having it flow as a liquid. We have to find 1.6 new Mississppiis today.
Actually, the problem is worse. As Greenland and the Antarctic melt only during about 4 months of every year, and not during the same time, whatever melt we have to produce during the year has to occur during an 8-month, not a 12-month period. If we have a global average of 1.6 new Mississippi discharges since 1980, then the actual discharge rate on an operating day basis has to be 2.4 Mississippis. And not 1.2 Mississippis each at opposite ends of the world. No: as Greenland is frozen when the Antarctic is melting, and vise versa, from August to September, there are 2.4 Mississippis worth of new meltwater coming off just Greenland, and then from November through February another 2.4 Mississippis worth of melting just from the Antarctic. And – taking the studies conclusions seriously, by January 2015, this increases to 2.7 new Mississippi Rivers (relative to 1980) draining Greenland and Antarctica on a rotating basis.
So where are they? We should already see them. The melt cannot be dispersed into a million rivers and impossible to recognize; the drainage of both icesheets isn’t like that.
The math is very simple. The mechanism is straightforward. The models are easy to understand. But where is the evidence? Where are the new Mississippis?
[BTW: aren’t these numbers out of sync with the new satellite data Hansen said was around 3.4 mm/yr (itself questionable)? But that is a different topic, though still a problem]
University of Colorado TOPEX and JASON data indicate a (60-day smoothed) 3mm per year mean sea level rise, with the trend since 2002 displaying a slight flattening:
http://sealevel.colorado.edu/current/sl_ib_ns_global.pdf
This trends is inconsistent with “accelerated” continental ice loss from Greenland and Antarctica, noting that steric expansion in the 1994-2000 time component of the Delta MSL trend accounts for part of this increase. It is of interest to speculate that the flattening of the Delta MSL-Time curve since 2000 may well be in accord with the absence of steric expansion resulting from global mean surface tenperatures displaying an absence of a warming trend.
R. Gates says:
March 10, 2011 at 11:37 am
Have you suddenly become 100% warmist?
Thanks R. Gates for the link, a very interesting JofC paper.
http://www.physorg.com/news/2011-03-earth-core-climate-insights.html
Another temperature proxy in need of “the trick” to hide the decline. The authors questioned everything for the breakdown in correlation except the GISS data.
Billy Liar,
Gates has always been 100% warmist. It’s in his nature.☺
Billy Liar says:
March 10, 2011 at 4:05 pm
R. Gates says:
March 10, 2011 at 11:37 am
Have you suddenly become 100% warmist?
______
I’ve never been 100% warmist, if by warmist you mean 100% convinced that AGW is happening.
Here’s where I stand, and what will change it one way or another:
I’m 75% convince that AGW is happening and is caused directly or indirectly by the build-up on anthropogenic GH gases– primarily CO2. I am current 25% “skeptic” in that I constantly look at other possible explanations for 20th century warming. Those other explanation include:
1) Unknown solar effects
2) Unknown ocean cycles
3) Unknown astronomical effects
Admittedly, I don’t put much real belief that there will be found some natural explanation other than AGW for the 20th century warming and related effects (such as sea ice decline, Greenland & Antarctica ice mass loss) but I try to be enough of a skeptic to actually put a few hours in each week of honest reading and research about the potential alternate explanations.
What events could cause me to become more of a skeptic?
1) A gradual turn-around in year-to-year arctic sea ice loss (ala what Joe Bastardi is expecting)
2) A 10 year period which does not show a warming trend decade over decade (i.e. if 2010-2019 is not warmer than 2000-2009 etc.)
3) A period of cold summer in which we see the majority of glaciers begin to grow, and even some areas of N. Cananda where the snowcover does not melt in the summer and new glaciers begin to form.
As it stands, I obviously doubt any of these happening, and in fact look for continued glacier, ice cap, and sea ice decline, and the decade to decade temps continuing to climb, and at some point (perhaps by 2020 at the latest) I expect to be 95%+ convinced in AGW, though hope to always reserve a bit of skepticism just because I never want to close my mind off from the chance of some new discovery.
wel says:
March 10, 2011 at 4:25 pm
Thanks R. Gates for the link, a very interesting JofC paper.
http://www.physorg.com/news/2011-03-earth-core-climate-insights.html
Another temperature proxy in need of “the trick” to hide the decline. The authors questioned everything for the breakdown in correlation except the GISS data.
———————————–
Exactly. If this is a good proxy for surface air temperatures, perhaps a better interpretation of the data would be in quantifying exactly how bad the purported surface air temperature data is due to UHI, other real reasons, Hansenization and other fabrications.
The problem with this particluar report is that its flashed aound all the medie here in Oz and even the Climate Change Minister is using it re the Carbon Tax. I rarely see the promptness (if at all) when a report comes out against the AGW. They still have full buy in to the AGW arguement in the establishment. Its going to take something dramatic to change it.
According to another paper from one of the coauthors, the actual contribution of Greenland to sea level rise should be negative: http://www.phys.uu.nl/~broeke/home_files/MB_pubs_pdf/2009_Ettema_GRL.pdf
Verity Jones, on her site ‘Digging in the Clay’ http://diggingintheclay.wordpress.com/
posted “Power and Fury” with two short videos of the ocean displaying some of its power around lighthouses off the coast of France.
My response was to comment, as follows:
An American novelist (Ivan Doig) has written books about Scots coming to the US and in one of those (Dancing at the Rascal Fair) one of the young men (Angus) tells a story of his great grandfather who worked on the Bell Rock Lighthouse, 11 miles off the county of Angus on the east cost of Scotland. One day as the tide comes there is no boat to take them back – but then it shows up. This seems to be the 200th anniversary.
http://www.bellrock.org.uk/
Also, claimed . . .
“The last sea-tower to be built in the days of sail.”
and
“The oldest sea-washed tower in existence.”
Also, info here:
http://en.wikipedia.org/wiki/Bell_Rock_Lighthouse
————————————
Being the 200th anniversary of the construction of this on a rock peaking just through the ocean’s surface one might suspect that it would be long ago submerged – being so close to the heartland of the industrial revolution.
However, there is a photo marker at the following coordinates (Google Earth) 56.413945, -2.405869
I wonder if the base is inspected occassionally to see if any repairs are needed and if there is any indication the ocean is any higher than in the past. The same goes for the lighthouses off the coast of France. Maybe there is a reader here that lives in the area and can inquire.
R. Gates says:
March 10, 2011 at 11:37 am
“The general trend of both Greenland and Antarctic continental ice, as well as most the major glaciers of the world is not in question…they are losing mass.”
R, dude, we have been through this before. Earth is dynamic. It is always changing. So, the fact that continental ice is losing mass is no news, at least not in itself.
If you could predict that continental ice will lose enough mass that the oceans will rise by four inches a decade over the next hundred years, then you would have our attention. But you cannot do that and neither can anyone else. You cannot because you have no set of physical hypotheses which can be used to make such predictions. You do realize that you have no such hypotheses, right?
If you could show a causal mechanism between increased concentrations of manmade CO2 and sea level rise of four inches a decade over the next hundred years, then you would have our attention. But you would need physical hypotheses to specify that causal mechanism. You are aware that you have none, right?
So, the sum total of your assertion is that continental ice mass is declining and manmade CO2 concentrations are increasing. Yet you have no idea whatsoever of some connection between them.
So, what are you asking us to do? Do you expect us to conclude that there is a connection when none can be specified in scientific terms? Do you believe we are fools? Al Gore believes we are fools. The AGW computer modelers believe we are fools. All they have are their hunches about the environment running as a computer simulation. Yet they too have no physical hypotheses that can be used to explain or predict sea level rise or the effects of rising CO2 on ice mass loss. Until you have the necessary physical hypotheses, you have nothing to say about the matter. Show humility. Express your hope that in forty years or so there will be a science of climate change based on real physical hypotheses. But there are none now. Nobody knows what sea level is going to do in the next ten or hundred years.
Enjoy the changes in ice mass along with the gazillion other changes that are happening all the time. End of story.
Wrong. The latest estimate from the new glacial isotatic adjustment models using new GPS data now shows that the rock below the center of the Greenland ice sheet is sinking not rebounding as previously thought. The new estimate is -230 GT/yr.
http://thegwpf.org/the-observatory/1438-ice-sheet-loss-cut-in-half.html
As a result Isostatic rebound now is called isostatic adjustment. Look at the before and after isosatic adjustment maps in the above link.
Doug Proctor says:
March 10, 2011 at 3:38 pm
Your “Reductio” argument is such a work of beauty that I am crying. Too bad the Warmista do not have a clue what you have just done. Being altogether averse to logic, they have not a clue what a “Reductio” is.
R. Gates says:
March 10, 2011 at 4:54 pm
I see your problem. Your time periods are way too short for the purposes of science.
Apparently, it the temperature was at a constant 15˚ C over Antarctica ice sheet all year round it still would take too long to even melt 1/5 of the ice.
Gates says:
“I’m 75% convince that AGW is happening and is caused directly or indirectly by the build-up on anthropogenic GH gases– primarily CO2. I am current 25% “skeptic” in that I constantly look at other possible explanations for 20th century warming. Those other explanation include:
1) Unknown solar effects
2) Unknown ocean cycles
3) Unknown astronomical effects”
Gates just gave us a perfect example of the argumentative fallacy, Argumentum ad Ignorantium: “Since I have no other explanation for the current Arctic cycle, then it must be due to CO2.”
Aside from the fact that there is no credible evidence showing that a few hundred parts per million of a minor trace gas is melting the Arctic, Gates ignores the elephant in the room: natural variability.
Three million years ago there was no Arctic ice cap. And wasn’t there a paper just submitted, IIRC, that said CO2 levels have been very low for the past 20 million years? So natural variability made the ice cap disappear naturally then, but Gates claims that now it’s different. Argumentum ad Ignorantium.
Drop the computer models, Gates, and step back. We need evidence, not GIGO. Where is your empirical, testable evidence that CO2 is melting the Arctic?
Or are you running on True Belief?
R. Gates says:
March 10, 2011 at 11:37 am
“Combine the shrinking year-to-year arctic sea ice, to ice mass loss in Greenland, Antarctica, and the majority (though not all) major glaciers around the world the 40% rise in CO2 since the 1700′s, and studies such as the one referenced above, and it would seem to get harder and harder to maintain a skeptics position. ”
====================
Please define “skeptics position”, as I may have one, but have yet to see a definition.
I think we are at the stage of this mania where those producing the evidence are simply blinded by their noble cause corruption.
Additionally, the new evidence that the ice sheets refreeze from the bottom calls into question the entire interpretation.
Unless CO2 changes the physics of water, and unless the AGW promoters can find evidence that somehow the deep water, against all evidence is warming, then there is a huge problem with the studies: The ice is not melting.
GRACE data can be interpreted by true believers all day long, but unless they can show a mechanism that causes melting in sub-freezing locations, they have a problem and they know it.
So much of AGW propaganda turns out to be magical thinking veneered over with science lingo. Sort of like a Start Trek dialog.
Here we go again … models … I think I have already said enough about them. Nothing to see here .. move along
Edit note for post:
Add to that, GRACE has it’s own set of problems. And at least one model conlcusion
its own set … conclusion
u.k.(us) says:
March 10, 2011 at 6:56 pm
R. Gates says:
March 10, 2011 at 11:37 am
“Combine the shrinking year-to-year arctic sea ice, to ice mass loss in Greenland, Antarctica, and the majority (though not all) major glaciers around the world the 40% rise in CO2 since the 1700′s, and studies such as the one referenced above, and it would seem to get harder and harder to maintain a skeptics position. ”
====================
Please define “skeptics position”, as I may have one, but have yet to see a definition.
______
My definition of skeptic…”I’m not convinced yet that x is happening and y is the cause. I’ll wait for more data”. Simple, but to the point.
Gates,
Wrong definition.
Skeptics merely say, “Prove it.”
But the alarmist crowd isn’t even close. They rely on True Belief.
From R. Gates on March 10, 2011 at 4:54 pm:
Thus you’re 75% “warmist”, and 25% scientifically-minded?
That would explain so much…
My son has reviewed his high school class on “the impact of climate change”. His teacher asserts that the seas will rise twenty feet or so and that the Arctic ice will disappear by 2050.
Theo Goodwin says:
March 10, 2011 at 5:43 pm
R. Gates says:
March 10, 2011 at 4:54 pm
I see your problem. Your time periods are way too short for the purposes of science.
_____
Hardly. But you also make the inaccurate assumption that science is only concerned with some specific time period…which is of course absurd. From nanoseconds to billions of years, science is concerned with it all and so there is no specific time period that is ‘way too short” for the purposes of science.
Now then, in regards to climate, once more, we see that science is concerned with all sorts of time scales…from the very short time period that LW radiation is absorbed and then re-emitted by the CO2 molecule, to the hundreds of millions of years that it takes our solar system to make a complete revolution about the core of the Milky Way…these vastly different time scales can have different effects on our climate. Zeroing in on the anthropogenic effects of CO2…one might imagine that science might want to look back at the history of CO2 in our atmosphere…especially when they can see exactly what it was, such as found in ice cores, but especially just prior to the rapid increase in CO2 beginning with the industrial revolution. Since that time, CO2 has increased some 40%, and so, science might want to study very closely what the expected natural variations the climate would be in that time frame up to the present…so over a few centuries down to a few decades. Especially significant would be the changes in climate over the past century or so as anthropogenic CO2 has really taken off.
So to suggest that climate science, or any science for that matter, should be concerned with some particular time scale is really quite silly…it just depends on what kind of effects you’re interested in studying…i.e. over what time scale are they likely to be seen.
I’ve said time and time again that if you want to consider sea-level rises then the key is to look at the impact. Where is the land that the globe is losing to these rapidly rising sea levels? Take a small island like the UK – how can we see how much land has been lost to the sea? Well for the last 50years or so we have accurate photographs taken for map purposes that would show exactly how much land we have lost to the sea over that period. Going further back we have accurate maps of the coast from the Navy that can be used to determine where the coastline is relative to certain unmoving landmarks such as lighthouses. Most of the UK is nowhere near the coast, so in percentage terms such measurements would give us land lost to the sea in those small areas at the coast to extraordinary precision.
Having done this already for Bangladesh in a simple way, the simple truth is that this low-lying nation has actually got bigger over the last 50 years and not smaller as TeamAGW would have us believe.
Ice breakup occurs at the edge of every ice sheet and glacier. It is normal because ice needs support from all sides and when the ice gets to the end of its travel is is not supported so it breaks up. But it is replaced by snow falling upslope/inland. This has to happen or the sheet or glacier would be very short lived. Kilimanjaro has lost ice cover because of lack of precipitation not rising temperatures. Temperatures there have remained doggedly below zero.
So does this new study take into account ice replacement by precipitation? I suspect not since this is a difficult if not impossible task. Without this vital information any ice loss data is meaningless and open to alarmist claims.
[snip – over the top – anthony]
As for the AGW/CAGW believers, apparently by disagreeing
1) you can’t show them the data is bad,
2) the interpretations are biased or inappropriate, and
3) the models on which their projections are inadequate.
By agreeing, apparently you can’t
4) show that their projections must have huge footprints right now, and
5) there is no evidence for the extreme things that must be happening right now.
We are in the same position as thoe at the latter end of the witch trials of the 13th through 17th century: the learned and self-thinking could not stop witch-mania, or even witch-hunting. For a while they succeeded in stopping the persecution by stopping the funding of witch-hunters, judges, cities, church and state by the sale of assets held by the “witches”. (Contrary to popular understanding, a great many rich and noble families were destroyed as witches.) It didn’t work all that well, as the political powers worked out a mutually beneficial way to split the profits and so get back into business.
Ultimately all those opposed to the witchcraft hysteria could do was, at great personal peril, stop specific “witches” from being burnt or hanged by appeal to the local jury. Over time the locals came to see that not just distant strangers but everyone was coming under suspicion – personal friends and families known by them to be innocent. And that their trial was surely coming. That was when the persecutions stopped: the absurdity of the state’s obsession with witchcraft had become a personal threat.
For climate change/whatever, we’ve gone through arguing against and with. De-funding is upon us. The final stage will be when”green” taxes and regulations stretch to make everything everyone enjoys unattainable. Bluntly put, what will really end the current mania is a carbon-tax of $3 on a bottle of beer, as beer has (or generates) CO2. Then this foolishness will stop. Let’s ask a congressman from Utah to help.
R. Gates, you state in regard to natural variables:
“Those other explanation include:
1) Unknown solar effects
2) Unknown ocean cycles
3) Unknown astronomical effects”
What is your opinion on the role of land use changes as documented by Pielke Snr. and others?
http://pielkeclimatesci.files.wordpress.com/2009/10/r-198.pdf
Also, by stating – in regards to what evidence would make you more ardent in your belief of AGW -that:
“in fact [I] look for continued glacier, ice cap, and sea ice decline…”
you appear to be exhibiting a confirmatory bias toward AGW which will probably render any objective reading of alternate possibilities unlikely. I mention this from personal experience. In the not so distant past I was not 75 percent but 110!
best wishes, ian
Anthony Watts says:
Well sure, it could be, but as this recent surprise study from GISS’s neighbors at Columbia illustrates, even though we’ve had the GRACE (Gravity Recovery And Climate Experiment) satellite looking at Antarctica, and concluding there’s been ice mass loss there, we have this new study that shows ice being added from underneath due to meltwater refreeze, concluding the models to be wrong.
You are creating a false dichotomy here.
The meltwater refreeze doesn’t contradict the GRACE data on mass balance. Whether we are looking at ice mass or ice volume, the numbers will be the same if there is meltwater underneath portions of the ice sheet on land or whether this is refrozen. If it is under the ice cap, it is counted as ice volume or mass.
There is no ice being added there. It is just changing its location from the top to the bottom of the ice sheet.
John Marshall says:
March 11, 2011 at 2:30 am
Ice breakup occurs at the edge of every ice sheet and glacier. It is normal because ice needs support from all sides and when the ice gets to the end of its travel is is not supported so it breaks up. But it is replaced by snow falling upslope/inland. This has to happen or the sheet or glacier would be very short lived. Kilimanjaro has lost ice cover because of lack of precipitation not rising temperatures. Temperatures there have remained doggedly below zero.
Kilimanjaro is not a typical mountain glacier. Don’t use it as a prototype example.
The ice on Kilimanjaro is disappearing because of sublimation, rather than melting.
So does this new study take into account ice replacement by precipitation? I suspect not since this is a difficult if not impossible task. Without this vital information any ice loss data is meaningless and open to alarmist claims.
Your suspicion is wrong. All you have to do is read to find this out.
The new study as described uses two methods of measurement. One looks at ice losses and gains, and the other looks at change in mass, which is the result of gain minus loss.
The study compared two independent measurement techniques. The first characterized the difference between two sets of data: interferometric synthetic aperture radar data from European, Canadian and Japanese satellites and radio echo soundings, which were used to measure ice exiting the ice sheets; and regional atmospheric climate model data from Utrecht University, The Netherlands, used to quantify ice being added to the ice sheets. The other technique used eight years of data from the NASA/German Aerospace Center’s Gravity Recovery and Climate Experiment (Grace) satellites, which track minute changes in Earth’s gravity field due to changes in Earth’s mass distribution, including ice movement.
ian says:
March 11, 2011 at 7:19 pm
R. Gates, you state in regard to natural variables:
“Those other explanation include:
1) Unknown solar effects
2) Unknown ocean cycles
3) Unknown astronomical effects”
What is your opinion on the role of land use changes as documented by Pielke Snr. and others?
http://pielkeclimatesci.files.wordpress.com/2009/10/r-198.pdf
Also, by stating – in regards to what evidence would make you more ardent in your belief of AGW -that:
“in fact [I] look for continued glacier, ice cap, and sea ice decline…”
you appear to be exhibiting a confirmatory bias toward AGW which will probably render any objective reading of alternate possibilities unlikely. I mention this from personal experience. In the not so distant past I was not 75 percent but 110!
best wishes, ian
_______
First, land use changes certainly play a role in the overall anthropogenic influence on climate. The Pielke Sr. et. al. study was really looking a regional climate influences from local land uses, and then, to a lessor extent, comparing these effects to the influence from the general global increase in CO2.
This study is interesting and really not at all surprising in its findings. Land use changes ought to cause regional climate changes, and one might expect these to be stronger (over some specified period) than the year-to-year increase in CO2 since the 1700’s. When looking at CO2, one must not look at the short-term year to year, or even decade to decade changes, but one must look at the CUMULATIVE change brought about by a 40% increase in CO2 since the 1700’s. From a geological and historical perspective, this 40% increase over a few hundred years represents a sudden spike in CO2, and nothing like this has happened in at least 800,000 years. I’ve likened this event to a human caused CO2 volcano that continues to erupt (i.e. we are 40% higher in CO2 and RISING).
Now, unlike many on this blog, I happen to have a great amount of respect for the sophistication and complexity of GCM’s and though I fully recognize that they are far from perfect, and will never get the exact details correct, I think they are very good at telling us trends. Their prediction, for example, of the first signs of global warming being seen in the Arctic, is right on target. Skeptics will poo-poo this and claim it is just natural variation, all happened before, etc., but I believe these skeptics don’t, won’t, or can’t fully appreciate how well the GCM’s agree on this, why they agree, and why the Arctic is generally responding as forecast (though perhaps even faster).
Aside from my belief that GCM’s generally have the trends correct (though the chaotic nature of the climate system will prevent them from every getting the details or even tipping points correct), everyday it seems new confirmatory research comes out that further validates the general tenets of AGW theory. For example, this study:
http://www.physorg.com/news/2011-03-earth-core-climate-insights.html
This is powerful confirmatory evidence that the GCM’s are generally right in the causes and trends they use in their scenarios.
I’ve stated many times what it would take for me to move my position from 75/25 warmist/skeptic. So far, I’ve seen very little evidence to move me more toward the skeptics camp, and more that would tend to move me more toward the warmist. I agree though, that there is a danger in having a jaded eye when reviewing alternative thought, but that’s a danger we all face from whatever position we have on any issue.
This summer’s Arctic sea ice looks to be falling very close to what we saw in 2007. If this happens- to what will the AGW skeptics attribute it? Their much beloved hero Joe Bastardi is expecting a higher summer low much higher than last year based on long term ocean cycles. If this doesn’t happen as Joe forecasts, but in fact we see a summer low hitting closer to 2007 or even lower, what new hypothesis will the AGW skeptics cling to? On the other hand, if the summer Arctic sea ice does indeed begin to rebound over the next few decades, then that single piece of evidence will be contrary in trend to every GCM forecast and would cause me to doubt the AGW theory greatly.
showing
RG;
Warming is not AGW. If the Arctic is ice-free for the next 10 Julys, it means nothing about CO2.
And it will/would be great for shipping.
But we’re into the cool half of the 60-yr cycle now, and there’s no hope of that.
@Tom Konerman
The data is available at CSIRO from Dec. 30th 1992 up to Dec. 30th 2010. It’s been there for quite some time now. I’ve seen that comment post many time of multiple blogs, but the data is there. I don’t know why people are saying the data isn’t there. Is it the data or some other product reprenting the data ?