Guest Post by Willis Eschenbach
This topic is a particular peeve of mine, so I hope I will be forgiven if I wax wroth.
There is a most marvelous piece of technology called the GRACE satellites, which stands for the Gravity Recovery and Climate Experiment. It is composed of two satellites flying in formation. Measuring the distance between the two satellites to the nearest micron (a hundredth of the width of a hair) allows us to calculate the weight of things on the earth very accurately.
One of the things that the GRACE satellites have allowed us to calculate is the ice loss from the Greenland Ice Cap. There is a new article about the Greenland results called Weighing Greenland.
Figure 1. The two GRACE satellites flying in tandem, and constantly measuring the distance between them.
So, what’s not to like about the article?
Well, the article opens by saying:
Scott Luthcke weighs Greenland — every 10 days. And the island has been losing weight, an average of 183 gigatons (or 200 cubic kilometers) — in ice — annually during the past six years. That’s one third the volume of water in Lake Erie every year. Greenland’s shrinking ice sheet offers some of the most powerful evidence of global warming.
Now, that sounds pretty scary, it’s losing a third of the volume of Lake Erie every year. Can’t have that.
But what does that volume, a third of Lake Erie, really mean? We could also say that it’s 80 million Olympic swimming pools, or 400 times the volume of Sydney Harbor, or about the same volume as the known world oil reserves. Or we could say the ice loss is 550 times the weight of all humans on the Earth, or the weight of 31,000 Great Pyramids … but we’re getting no closer to understanding what that ice loss means.
To understand what it means, there is only one thing to which we should compare the ice loss, and that is the ice volume of the Greenland Ice Cap itself. So how many cubic kilometres of ice are sitting up there on Greenland?
My favorite reference for these kinds of questions is the Physics Factbook, because rather than give just one number, they give a variety of answers from different authors. In this case I went to the page on Polar Ice Caps. It gives the following answers:
Spaulding & Markowitz, Heath Earth Science. Heath, 1994: 195. says less than 5.1 million cubic kilometres (often written as “km^3”).
“Greenland.” World Book Encyclopedia. Chicago: World Book, 1999: 325 says 2.8 million km^3.
Satellite Image Atlas of Glaciers of the World. US Geological Survey (USGS) says 2.6 million km^3.
Schultz, Gwen. Ice Age Lost. 1974. 232, 75. also says 2.6 million km^3.
Denmark/Greenland. Greenland Tourism. Danish Tourist Board says less than 5.5 million km^3.
Which of these should we choose? Well, the two larger figures both say “less than”, so they are upper limits. The Physics Factbook says “From my research, I have found different values for the volume of the polar ice caps. … For Greenland, it is approximately 3,000,000 km^3.” Of course, we would have to say that there is an error in that figure, likely on the order of ± 0.4 million km^3 or so.
So now we have something to which we can compare our one-third of Lake Erie or 400 Sidney Harbors or 550 times the weight of the global population. And when we do so, we find that the annual loss is around 200 km^3 lost annually out of some 3,000,000 km^3 total. This means that Greenland is losing about 0.007% of its total mass every year … seven thousandths of one percent lost annually, be still, my beating heart …
And if that terrifying rate of loss continues unabated, of course, it will all be gone in a mere 15,000 years.
That’s my pet peeve, that numbers are being presented in the most frightening way possible. The loss of 200 km^3 of ice per year is not “some of the most powerful evidence of global warming”, that’s hyperbole. It is a trivial change in a huge block of ice.
And what about the errors in the measurements? We know that the error in the Greenland Ice Cap is on the order of 0.4 million km^3. How about the error in the GRACE measurements? This reference indicates that there is about a ± 10% error in the GRACE Greenland estimates. How does that affect our numbers?
Well, if we take the small estimate of ice cap volume, and the large estimate of loss, we get 220 km^3 lost annually / 2,600,000 km^3 total. This is an annual loss of 0.008%, and a time to total loss of 12,000 years.
Going the other way, we get 180 km^3 lost annually / 3,400,000 km^3 total. This is an annual loss of 0.005%, and a time to total loss of 19,000 years.
It is always important to include the errors in the calculation, to see if they make a significant difference in the result. In this case they happen to not make much difference, but each case is different.
That’s what angrifies my blood mightily, meaningless numbers with no errors presented for maximum shock value. Looking at the real measure, we find that Greenland is losing around 0.005% — 0.008% of its ice annually, and if that rate continues, since this is May 23rd, 2010, the Greenland Ice Cap will disappear entirely somewhere between the year 14010 and the year 21010 … on May 23rd …
So the next time you read something that breathlessly says …
“If this activity in northwest Greenland continues and really accelerates some of the major glaciers in the area — like the Humboldt Glacier and the Peterman Glacier — Greenland’s total ice loss could easily be increased by an additional 50 to 100 cubic kilometers (12 to 24 cubic miles) within a few years”
… you can say “Well, if it does increase by the larger estimate of 100 cubic km per year, and that’s a big if since the scientists are just guessing, that would increase the loss from 0.007% per year to around 0.010% per year, meaning that the Greenland Ice Cap would only last until May 23rd, 12010.”
Finally, the original article that got my blood boiling finishes as follows:
The good news for Luthcke is that a separate team using an entirely different method has come up with measurements of Greenland’s melting ice that, he says, are almost identical to his GRACE data. The bad news, of course, is that both sets of measurements make it all the more certain that Greenland’s ice is melting faster than anyone expected.
Oh, please, spare me. As the article points out, we’ve only been measuring Greenland ice using the GRACE satellites for six years now. How could anyone have “expected” anything? What, were they expecting a loss of 0.003% or something? And how is a Greenland ice loss of seven thousandths of one percent per year “bad news”? Grrrr …
I’ll stop here, as I can feel my blood pressure rising again. And as this is a family blog, I don’t want to revert to being the un-reformed cowboy I was in my youth, because if I did I’d start needlessly but imaginatively and loudly speculating on the ancestry, personal habits, and sexual malpractices of the author of said article … instead, I’m going to go drink a Corona beer and reflect on the strange vagaries of human beings, who always seem to want to read “bad news”.
Hi, Willis,
Corona sucks! Never drink a beer that comes in clear glass bottles. Light makes beer go soft. Why don’t you try any of those 9º alcohol beers as Canadian Maudite, or good Belgian Lambics as Chimay? I wouldn’t recommend Samuel Adams’ Special edition of at $1,000 the 1 liter bottle, but maybe you can convince Bill Gates or Michael Mann to invite you one… they handle big money, you know 😉
BTW, excellent post. It goes into Spanish to our wesite -with your permission, of course.
Well, here it comes! The pseudoscience called Conservation Biology, the twisted sister of IPCC ‘global climatology,’ will soon become more of a headliner.
This “mission-oriented science” begins with the premise that everything is going extinct. Evidence, schmevidence, its an emergency!
—————
UN says case for saving species ‘more powerful than climate change’
Goods and services from the natural world should be factored into the global economic system, says UN biodiversity report
• Economic report into biodiversity crisis reveals price of consuming the planet
Juliette Jowit guardian.co.uk, Friday 21 May 2010
http://www.guardian.co.uk/environment/2010/may/21/un-biodiversity-economic-report
————
You like junk numbers? From this article…
“The International Union for the Conservation of Nature has previously estimated that species are becoming extinct at a rate 1,000 and 10,000 times higher than it would naturally be without humans.”
Sadly, even though there is a very genuine basis for concerns here, the IPCC gang has nothing on these folks for hysterical and unfounded allegations. It all sounds soooo scary until you look into the actual details. Just like this Greenland case only, if you can believe it, worse.
Willis, your teaching is, once again, absolutely brilliant. Occaisonally, those of us who taught practical stuff to kids got inspired, but you seem to be inspired most of the time.
One of my bursts of inspiration came when attempting to teach twelve-year-old high school kids how a gear train works – I drew some illustrations on the chalk-board, then got the kids up on their feet, pushed the furniture back to the edges of the room then had them form three rings, holding hands with their partners. I then got them to do a sort of folk dance, with me as caller and pushing and pulling kids in the approriate directions. It was energetic, it was fun and it worked; the kids soon realised how each meshed gear reversed direction from the gear it meshed with as the three gears thrashed about the classroom. When we had got our breath back, we spent the rest of the period with them drawing gear trains using various ratios.
Senior high school kids everywhere should be exposed to your clear and enlightening posts/teaching as an antitdote to being frightened by the nonsense promulgated by alarmists which comes packaged as science.
Al Gored says:
May 24, 2010 at 1:03 am
Can somebody list 10 (ten) species that have become extinct (100% certified human and/or natural causes) in the last 100 (one hundred) years?
Thank you Al
An interesting but underwhelming analysis on what is happening to the second largest (9.8%) ice inventory on Earth. Cannot wait for the analysis of what is happening in Antarctica which contanes 89.8% of the world’s ice. But don’t hold your breath. Since temperatures near the South pole have been declining over the last few decades and periodically weather stations have to be rebuilt to replace the ones getting buried in snow and ice, any analysis here would negate the one for Greenland and then some by at least 9 to 1.
This month’s National Geographic claims that the annual Greenland ice loss is 50 cubic miles (approx 80 cubic kilometres) and the ice sheet will disappear over the coming centuries.
We’re all doomed…assuming we live to about 18052!
An interesting history of the Greenland climate from the Royal Danish Ministry of Foreign Affairs:
http://www.um.dk/Publikationer/UM/English/Denmark/kap7/7-1-19.asp#7-1-19
Until around 4500 BC, the remains of the mighty ice cap which had been left over from the last ice age covered parts of Arctic Canada and blocked the way to Greenland. The first people arrived in the northernmost part of Greenland in around 2500 BC, and in the course of a few hundred years the ice-free part of the island became home to an Arctic tribe of hunters known as the palaeo-Eskimos. The warmer climate which appeared once the ice had gone allowed the population to increase rapidly.
Towards the end of the 10th century the climate became warmer, and the change affected all those living in the northern hemisphere. Much of the ice in the seas around the Canadian archipelago disappeared, and baleen whales moved into the area to search for food. Eskimo whalers from northern Alaska sailed east in their large, skin-covered boats and reached Greenland in the 12th century.
Prefering to think of things visually, I did a quick calculation. If you represent Greenland by a block of ice 1.3m x 1.3m x 1.3m, the volume lost per year would be 1mm x 1mm x 1mm (using the minimum of Willis’ figures for Greenland ice volume). For those of you who prefer feet and inches, think 4ft per dimension for the big block and <1/16th inch for the block representing the portion lost each year. I would have drawn it, but for something drawn to scale that fits on a blog page the block representing ice loss per year is almost too small to see.
Willis , good news rarely sells newspapers and definetly won’t panic government into signing off a large funding proposal. Things are always unexpected, unprecedented and “worse than we thought” . Not just in climate matters either, See Elizabeth Pisani’s “wisdom of whores”* on how data was “beaten up” to generate publicity and increase access to funding for HIV/AIDS programs and how not always optimum results have been achieved with the spend. And their problem was at least visible in a microscope and the treatment verifiable by double blind testing. In fact what she calls “the AIDS industry” should be seen as a template for the waste and misdirection that will occur once the funding cycle shifts from “research” into “intervention”
* I don’t often wax lyrical but this is one book that should be compulsory reading in all schools and sod the Texas school board….:-)
“melinspain says:
May 24, 2010 at 3:02 am
Al Gored says:
May 24, 2010 at 1:03 am
Can somebody list 10 (ten) species that have become extinct (100% certified human and/or natural causes) in the last 100 (one hundred) years?
Thank you Al”
Madeiran Large White Pieris brassicae wollastoni, declared extinct on 29-30 October 2007
Pyrenean Ibex, Capra pyrenaica pyrenaica, 6 January 2000
Zanzibar Leopard, Panthera pardus adersi, 1996
Atitlan Grebe, Podilymbus gigas, 1987
Holdridge’s Toad, Incilius holdridgei, 1986
Bali Tiger, Panthera tigris balica, 1972
Santo Stefano Lizard, Podarcis sicula sanctistephani, 1965
Thicktail Chub, Gila crassicauda, 1957
Japanese Sea Lion, Zalophus japonicus, 1950s
Tasmanian Tiger, Thylacinus cynocephalus, 7 September 1936
More on :
http://www.petermaas.nl/extinct/mostrecent.htm
Fear mongers to gain political control – real scientists (and journalists) are insulted.
Yes, the ICE melts.(and ‘disappears’)
Then, the ICE freezes. (and ‘reappears’)
Dr. Lindzen is saying Ice Age in the future, I will go with that.
Obviously, there was a very significant warming to allow Farming by the Vikings in Greenland.
There is an awful lot of money being spent to nano-analyze what any good scientific reference will show. Earth warms – then cools, uh- really!
Perhaps if man kind blew the entire nuclear arsenal, we might have a temporary effect – but the earth will rapidly (in the earths time frame) reach equilibrium without us.
Equilibrium – all systems seek it! (including the earth and political) –
The point Willis is making is not about the ICE but about the FEAR MONGERING TACTICS used to gain political control.
“@Charles S. Opalek, PE
An interesting but underwhelming analysis on what is happening to the second largest (9.8%) ice inventory on Earth. Cannot wait for the analysis of what is happening in Antarctica which contains 89.8% of the world’s ice. But don’t hold your breath. Since temperatures near the South pole have been declining over the last few decades and periodically weather stations have to be rebuilt to replace the ones getting buried in snow and ice, any analysis here would negate the one for Greenland and then some by at least 9 to 1.”
ICE melts, ICE freezes, the earth is moving, etc., I am glad who ever set this whole system up was smarter than all of the ‘scientists’ around.
Remember that with all seriousness various alarmists claim that if it gets warmer, the Greenland glaciers will slide into the sea, whoosh, just like that. Even though the bulk of the ice is in a large basin at very high elevation that does not really get above freezing ever. Which is why it is still there when the rest of the Pleistocene ice cap has vanished.
Ernest Hemingway once fondly recalled his favorite ad from his youth: “Drink xxxx-brand beer in brown bottles and avoid that skunk taste.”
MaxL says:
May 23, 2010 at 4:01 pm
Nope, you are correct.
Bulldust says:
May 23, 2010 at 5:47 pm
Ummm .. because when I opened my refrigerator, that was what was there? …
Eduardo Ferreyra says:
May 24, 2010 at 12:01 am
Andele pues, amigo.
If one wonders why poeple of the skeptic side get annoyed. after reading the above guest post, I went to one of the warmist sites and they are rubbing their hands in glee over the following article.
in which it states we have several lines of independant “evidence”, yet throughout the article you see the words, believed, possible, and probable.
Does anyone else get frustrated with the warmist side or is it just a few of us?
Monday, 24 May, 2010
Greenland rising faster as ice loss accelerates
We have several independent lines of evidence that Greenland is losing ice at an accelerating rate. Satellite altimetry find glaciers are sliding faster downhill and dumping more ice into the ocean. Altimetry data also find the ice sheet is thinning. An overall picture is obtained by satellites measuring the gravity around the ice sheet. Another line of evidence has now been added to this picture with GPS measurements finding that Greenland is losing ice so quickly, the land is now rising up at an accelerating rate.
These results are published in Accelerating uplift in the North Atlantic region as an indicator of ice loss (Jiang 2010). The study looks at high-precision global positioning system (GPS) data that measure the vertical motion of the rocky margins around Greenland, Iceland and Svalbard. The weight of ice sheets push down on the bedrock it rests on. As the ice sheets lose mass, the bedrock rises. This process, known as Glacial Isostatic Adjustment (GIA), has been happening since the planet came out of an ice age around 17,000 years ago. How do we know whether current uplift might be a delayed response to glacial retreats from thousands of years ago? To avoid the effect of past events, this study focuses on vertical acceleration rather than velocities. The results are therefore insensitive to GIA-related motions from past ice mass changes.
What they find is crustal uplift in Greenland, Iceland and Svalbard is accelerating. Extrapolating the acceleration backwards in time finds the acceleration began after 1990. The acceleration of uplift over the past decade represents an essentially instantaneous, elastic response to recent accelerated melting of ice throughout the North Atlantic region.
Figure 1: GPS measurements for the North Atlantic region. The numbers (eg – 0.6 mm/yr2) show the amount of acceleration. The red (upper) time series (Greenland, Iceland) show positive acceleration and the blue (lower) time series (Fennoscandia, Canada) show no significant acceleration.
From the rates of uplift around Greenland, they estimate ice loss is accelerating at 21.2 gigatonnes/yr2. This agrees well with other estimates of ice loss accelerating at around 21 gigatonnes/yr2. The following shows estimates of the rate of Greenland ice loss measured from satellite altimetry, GRACE gravity data and net accumulation/loss measurements.
Figure 2: Rate of ice loss from Greenland. Vertical lines indicate uncertainty, horizontal lines indicate averaging time. Blue circles are from altimetry, red squares are from net accumulation/loss and green triangles are from GRACE. The black line is a straight-line (constant acceleration) fit through the mass balance data for the period 1996–2008 with a slope of 21 gigatonnes/yr2.
So combining altimetry, net accumulation/loss, GRACE gravity data and GPS measurements, we find multiple lines of evidence converging on a single answer: Greenland is losing ice mass at an accelerating rate. If this acceleration continues, Greenland could soon become the largest contributor to global sea level rise
Lastly, one interesting point. The amount of uplift in Greenland varies from location to location, from 1.4 mm per year in northwest Greenland to over 10 mm per year in other places. In some locations, this exceeds the current rate of global sea level rise which is around 3.2 mm per year. Greenland’s uplift rate is predicted to double by 2025. Sadly, this doesn’t mean we can now relax about sea level rise – unless you have a huge melting ice sheet in your neighbourhood, you’re unlikely to see uplift rates like those seen in Greenland.
Recently a paper reported that the amount of ice loss from Greenland was accelerating.
http://www.nature.com/ngeo/journal/vaop/ncurrent/abs/ngeo845.html
From that information and a little calculation, perhaps if that acceleration continues the Greenland Ice Sheet could be gone in between 426 and 670 years.
But it is all cyclical, so I would predict the ice loss will stop accelerating and the ice loss will diminish or even stop dimimishing and increase.
Willis Eschenbach at 11:04 am said:
Nope, you are correct.
To – MaxL (May 23, 2010 at 4:01 pm) that said:
……..the percent rate seems to be stated as a constant .007% per year. This only works for the first year. The percent rate will increase exponentially as the volume of ice decreases while the loss rate remains constant.
That means in 17011 we’ll have a 100% ice loss year! Thank God I’ll be on the third planet from Gliese 581 that year on a fact finding mission for The Federation.
1personofdifference at 11:39 am asked:
Does anyone else get frustrated with the warmist side or is it just a few of us?
YES!
During my morning commute today, there was a time interval during which my hybrid automobile went from 10 MPH to 20 MPH over a span of 3 seconds (~3.33 MPH/sec), and then from 20 MPH to 50 MPH over a span of 6 additional seconds (5 MPH/sec).
Hence, in 9 seconds, the speed of the vehicle accelerated by 5/3.33 = 1.5 times.
Extrapolating this acceleration, we see that every 9 seconds the speed will increase by a factor of 1.5.
Roughly 60 seconds later, my car will break the sound barrier. After a total of 140 seconds, my car will reach escape velocity for planet Earth. Within six minutes, it will be going roughly 82.5% of the speed of light (in a vacuum), at which point relativistic effects will begin dominating the rest of my trip… which, due to time dilation, should allow me to reach any point in the universe in no more than an hour or so subjective time.
Barry Kearns says:
May 24, 2010 at 2:11 pm
Don’t be silly – hybrid space vehicles reach a maximum velocity, then coast at a constant rate for 12,000 to 19,.000 years.
Like Voyager 2.
It’s a question of fuel.
Nah, I’ve got regenerative braking on my hybrid, so I should get going as fast as possible. That way, the energy that I recapture on the braking leg should be enough to power an industrial civilization at the destination end for quite some time.
Plus, I got a nice tax credit.
As I said before, John Wayne is credited as having said that “life is tough and it’s tougher if you’re stupid”. Remember, that by definition, the average IQ is 100 which leaves a huge portion of the population below that level. Room temperature IQ’s can now obtain any degree they desire if they have the time and money: PHD, MD, no area of education is exempt from this rule. A hundred or so years ago if you were stupid you might not make it to pass along your weak genes. Not so more recently. Most people today would not even grasp the meaning of .007%. The 15000 years, maybe, but they would probably still be worried. There ain’t no cure for stupid.