Guest Post by Willis Eschenbach
Charles the Moderator has been doing a fantastic job of keeping WUWT humming along, and deserves everyone’s thanks. Today he sent me an interesting article thinking I might want to comment on it. It has the usual kind of alarmist headline, viz:
Greenland lost 11 billion tons of surface ice in one day
YIKES! EVERYONE PANIC!
Now, I’ve gotta admit that that sounds like a lot of ice, eleven billion with a “b” tonnes melted in one single day. However, I’m a tropical boy, so I’m kinda prejudiced in these matters. Here’s my conflict of interest statement. When I’m in a place where the ice jumps up out of my adult beverage and starts running around the landscape, I consider that to be “water behaving badly” whether it’s one cube or eleven billion tonnes, and I try to avoid such locations … but I digress.
To return to the question, is eleven billion tons of ice really a big number or not?
Well, to start with, it’s a one-day loss in the warmest part of the year. Snow builds up on the ice sheet in the winter, and melts, sublimates, and is lost in icebergs in the summer. So this one-day loss tells us very little about the longer-term changes, what is called the “mass balance” of an ice sheet over an entire year or a longer period.
So what is happening in the longer term? A source for some information on this question is the Polar Portal. There’s a good article to start with, the annual report for 2018. (It also has an interesting article on the various phenomena involved in the mass balance here.)
Let me start with a look at the mass balance of the Greenland ice sheet since 1972. Here’s that data.
From that data, we find that the 1981 – 2010 thirty-year average mass balance for the Greenland ice sheet was a net loss of 103 billion tonnes. Again, this is a very large number, it seems like a big deal that would demand our attention … but is it really?
In order to ask the question “How big is 103 billion tonnes?”, we have to ask a related question:
“Compared to what?”
In this case, the answer is, “Compared to the total amount of ice on Greenland”.
Here’s one way of looking at that. We can ask, IF Greenland were to continue losing ice mass at a rate of 103 billion tonnes per year, how long would it take to melt say half of the ice sheet? Not all of it, mind you, but half of it. (Note that I am NOT saying that extending a current trend is a way to estimate the future evolution of the ice sheet—I’m merely using it as a way to compare large numbers.)
To answer our question if 103 billion tonnes lost per year is a big number, we have to compare the annual ice mass loss to the amount of ice in the Greenland ice sheet. The Greenland ice sheet contains about 2.6E+15 (2,600,000,000,000,000) tonnes of water in the form of snow and ice.
So IF the Greenland ice sheet were to lose 103 billion tonnes per year into the indefinite future, it would take about twelve thousand five hundred years to lose half of it …
And even if the loss were to jump to ten times the long-term average, it would still take twelve hundred years to melt half the ice on the Greenland ice sheet. Even my great-great-great-great-great-great-great-great-great-great grandchildren won’t live long enough to see that.
However … there has been no big trend in mass losses in Greenland. As you can see in the graph above, it went down starting in 1980 but has generally risen since about 2010 … go figure.
Let me close with another way to visualize the mass loss of the Greenland ice sheet using two graphs. The first graph shows the cumulative loss over the forty-six year period of the record. This is how it would commonly be shown.
It’s shown that way because, well, it looks pretty scary. It looks like the ice sheet is about to disappear.
By contrast, here’s a more honest way to display the loss, by showing not the annual or cumulative anomalies, but instead showing the changes in the total mass of the Greenland ice sheet:
Not as scary, huh?
As a result, I’d say that there’s no need to worry about Greenland at this time. As Sanjeev Sabhlok recently wrote in a most reasonable article in the Times of India:
The best policy today is to (a) abandon socialism (Why does IPCC not talk about this ideology which is causing mankind the most harm?), and (b) to do everything possible to maximize the wealth of the current generations. Then review the [climate and energy] situation in 2050 when more data and new technologies become available.
In the meanwhile, there’s no harm in installing as many nuclear plants as are viable and growing more trees. And we can keep researching alternative energy technologies. However, interventions to divert precious resources into uneconomic solar and wind energy are the surest way to harm future generations.
The climate change alarm movement is driven by extremist socialists. Ultra-socialist Saikat Chakrabarti, who prepared Alexandria Ocasio-Cortez’s Green New Deal, exposed the underbelly of climate change alarmism when he confessed that “The Green New Deal wasn’t originally a climate thing at all. We think of it as a how-do-you-change-the-entire-economy thing”. The CO2 panic is a socialist harangue dressed in a veil of bad science.
Can’t say fairer than that …
Best to everyone, I’ve got to go outside now and get some work done ..
w.
PS. H/T Mona~ctm
Greenland has about 1.8 million square kilometer. This is 1.8e12 square meter. The specific weight of ice is 0.9. This means with the 11 billion tons is 11e12kg, that’s 6.1 kg per m2 which is 6.7.mm los on one warm day. This is not much, I think.
Thats pretty revealing. Look at figures 2 and 3 – see something. The numbers look big but in the total scheme of things, they are virtually meaningless. Oh, sue the Alarmists conveniently forget that temperatures went down for some years now and the ice comes back with a vengeance. We lost – virtually nothing. We gain it back in a few years and as we are entering a protracted solar minimum now, there will likely be a lot more ice than the starting point not long from now. The Netherlands might be able to live without all their dikes someday in the not so far future.
Anyone here actually been to Greenland besides me? Way back in ’70 or ’71. As a pilot in the AF. We flew to Thule from Georgia in a C-141. Landed going east; next day turn around take off going west. Mountains the other way. The ice age was coming at the time. You can see it up there.
I fly over Greenland frequently. Recently I was looking out over all the sea ice surrounding it, and someone remarked, with absolutely no idea of our location, “Oh, there used to be so much more!” Maybe she worked for PBS News
So, would the 103 billion be about .00003% of the total in Greenland?
Cycles matter, especially large ones nearby.
Chris
Surely one Manhattan is enough.
Considering the way they vote.
🙂
From the article: “However … there has been no big trend in mass losses in Greenland. As you can see in the graph above, it went down starting in 1980 but has generally risen since about 2010 … go figure.”
Yes, 1980 was about the time climate scientists gave up on the human-caused Global Cooling speculation and started in on the human-caused Global Warming speculation. That would be because the temperatures started warming up around then instead of cooling as they had been doing for decades. So the climate scientists had to do an aboutface!
So the graph covers a cold period (1980) warming up to a warm period (the present day). But the mass starts increasing around 2010, so maybe this is an indication of cooling. Or should I say another indication of cooling.
I watched ABC cover this news event the other day and they showed a rushing river of water flowing from somewhere as they fed the CAGW narrative to the people watching. Thanks for putting things in perspective. We can always count on getting the other side of the story here at WUWT.
Greenland ice fields cover 1,710,000 sq km
Million sq metres per sq km equals 1,710,000,000,000 sq metres.
Ice weighs 919 kg cubic metre.
1,000,000,000 tonnes of ice equals 11,963,532,100 cubic metres lost.
Divide that by the area.
7mm surface ice lost.
Who claims they can measure 1,710,000 sq km to that accuracy each day?
http://polarportal.dk/en/greenland/surface-conditions/
You must include calving in your calculation.
“The map illustrates how the surface of the Greenland Ice Sheet gains and loses mass on a daily basis. This is known as the surface mass balance. It does not include the mass that is lost when glaciers calve off icebergs and melt as they come into contact with warm seawater”
Anthony & CTM, I just sent an email regarding this subject to your manuscript email address. I would appreciate your replying to that. Sorry for doing it this way, but I think you’ll see why in the email. Thanks.
ESA published a similar alarmist article about this last month.
Some years ago (some might now say many years ago), a commenter at Bishop Hill put forward a simple back-of-an-envelope calculation matching the asserted ΔH effect on the Earth from postulated extra CO2 in the atmosphere, with the accumulated ΔH needed to melt the Greenland ice sheet.
I found no fault in the calculations, and I’m too lazy to repeat the exercise now, but it came to many thousands of years… And that is if all the global warming was always concentrated into the relatively small area of Greenland.
Is it a meaningful calculation? In an absolute sense, probably not. It’s the sort of thing that the MSM broadcasts all the time. But it does help put things in perspective if/when somebody is trying to present both sides of an argument.
There is no such thing as a general scientist’s professional oath, board of professional standards, or even professional commitment (maybe if they adopted one, pay-rates ultimately might rise for the honest and competent). But if a scientist cannot commit to some form of disinterest above and beyond the needs of politics, fame or funders (whether private or public) then we have nothing. That’s how we ended up with people like Michael Mann.
I’ve been following DMI and polar portal Greendland ice reporting for the last few years, when it has been accumulating, and when it has been melting, too. My conclusion is that the pesistence of storms, or clear sunny skies, have their effects. Storms bring increases in DMB, and sunny skies bring melting.
It seems to me that the ’12-GT’, 1-day SMB acculations occur when strong, wet low pressure systems approach the island from the southwest, and hit mid-island. A somewhat slower accumupation occurs when a low pressure systm parks off the SE coast of the island, and sits there for 3-5 days.
In the years when the weather does not do this, accumulations are less. If those years also are sunny in the summer, total SMB is lower as the melt season completes.
The alarmists will obviously counter that the +12GT of SMB was certainly due to “climate change”, just like the -11GT and any other change. If it stayed the same, that would be sure to “climate change” too.
All of Greenland’s ice melting would rise sea levels by about 6 meters. So losing 0.2% so far means a sea level rise of about 1.2 centimeters has occurred.
The Antarctic ice sheet has about ten times as much ice; so it’ll also cause sea level rises (with a higher ceiling, but I’m not sure it’s melting at the same ratio so far).
As for the melting pace, it’s highly irregular, but the trendline points towards an average loss of about 250 b tons/year at the moment. So still not as bad as the worst years were.
But yeah if we just stop our greenhouse gas emissions soon we wont have to worry about the Greenlandic ice sheet because so far the melting hasn’t been THAT bad.
The sharp fall of 11 Gt began from the peak of a ~ 6 Gt rapid gain of ice. Now from the nadir of the 11 Gt down-fluctuation, the ice has regained about 3 Gt already. So it’s almost back where it started a few days ago.
Just wondering how many mm ( or micrometers ) is 103 billion tonnes of water spread across the worlds oceans?
WonkyPedia tells us oceans cover 360 million square kilometers = 360 * 10^12 m^2
A tonne of water is a cubic metre.
103 * 10^9 m^3 / 360 * 10^12 m^2 ~= 0.3 mm/y
oo-err. We’re dooomed , I tell yer, we’re all doooomed.
In one month Greenland lost as much ice as it has on average over a year (using figures 2002-2018).
a year’s worth.
It saw melt at its highest point, where evidence shows on average melt has occurred once in 250 years (last time in 2012, btw).
I don’t see how you can just explain all this away?
Explain it away? It’s already almost gone away.
The sharp fall of 11 Gt began from the peak of a ~ 6 Gt rapid gain of ice. Now from the nadir of the 11 Gt down-fluctuation, the ice has regained about 3 Gt already. So it’s almost back where it started a few days ago.
Apparently you weren’t paying attention, Griff. The one-month loss is akin to throwing bricks into the Grand Canyon one at a time in an attempt to fill it up. No one would notice.
NOT true. The Forest Rangers would fine you for littering.
It’s easy to explain.
There are cycles in nature that are longer than the annual cycle.
What is it about trolls and there desperate need to believe that if anything is different from last year, it must be the fault of CO2.
I must confess, I had to get to the spoiler….which is going up on a poster and getting pinned on Twitter for all to see…I just hate when they act like all the Arctic ice is going to be gone in the next 50, 40, 12 years…. If this doesn’t “cure” people of their foolishness, nothing will.
“To answer our question if 103 billion tonnes lost per year is a big number, we have to compare the annual ice mass loss to the amount of ice in the Greenland ice sheet. The Greenland ice sheet contains about 2.6E+15 (2,600,000,000,000,000) tonnes of water in the form of snow and ice.
So IF the Greenland ice sheet were to lose 103 billion tonnes per year into the indefinite future, it would take about twelve thousand five hundred years to lose half of it …
And even if the loss were to jump to ten times the long-term average, it would still take twelve hundred years to melt half the ice on the Greenland ice sheet…..”
For a little more “perspective“…
Based on the asserted loss of ice since 1900, the Greenland Ice Sheet (GrIS) has lost the equivalent of a Lake Superior-sized ice cube. However the GrIs remained larger than the Gulf of Mexico (by volume) despite losing a Lake Superior. The Gulf of Mexico has a volume of about 2.5 million km3. If the GrIS melted, the volume of water would be about 2.71 million km3. Before losing Lake Superior, the water volume was 2.72 million km3.
99.58% of the Greenland Ice Sheet has not melted since 1900.
Tabone et al., 2017 devised a model to simulate how the GrIS has evolved over the past 250,000 years. Using the maximum basal melting scenario (Bref = 40), I tacked the modern GrIS volume profile on to their model.
Who would have guessed that the “Anthropocene” GrIS is actually larger than it was during the Late Pleistocene? WUWT? X-axis is in calendar years AD(BC). Notice something funny? The GrIS may have actually been smaller than it currently is from 35 ka to 15 ka. And, this actually might make sense. Of course, the lower basal melting scenarios would reverse this… And they would also make the modern ice loss even more geologically insignificant.
Vinther et al., 2009 reconstructed the elevations of four ice core sites over the Holocene. There has been very little change in elevation of the two interior ice core sites (NGRIP and GRIP), while the two outboard sites (Camp Century and DYE3) have lost 546 and 342 m of ice respectively.
Elevation profiles: End Pleistocene and 2000 AD.
Most of the melting since the beginning of the Holocene has occurred on the outboard, lower elevation portions of the GrIS – Same as it ever was.
Thank you for the profiles. It is very telling that Greenland looks like a shallow, very broad “basin” that traps the center ice against the tall “walls” of the bowl around the edges. It is only the 60 kilometers between the shore and the rim mountains that allows the glaciers on the edge to slide into the oceans. In the graphic, both Dyes and Camp Century are on the inside edges of the central bowl.
https://apnews.com/65694195c91d4b62b275bd14a6955b4c
1 Gt ice loss = 400,000 Olympic-sized swimming pools
How Big is the Greenland Ice Sheet?
According to U.S. Geological Survey Professional Paper 1386–A (2012), the volume of the GrIS is 2,600,000 km3.
Ice: tonne per cubic meter (t/m³) 0.9167.
2,600,000 km3= 2,383,420 Gt
Greenland Ice Sheet = 953,368,000,000 Olympic-sized swimming pools… almost 1 trillion Olympic-sized swimming pools.
Flying up on Mt. Mckinley today for a glacier landing. Here’s the forecast:
https://www.mountain-forecast.com/peaks/Mount-McKinley/forecasts/6194
Glad I brought my extreme wx poly longjohns…
How big is 11B tons of ice?
First, remember, there are SCARY headlines and SCARE headlines. There is a difference and the article references is the latter.
By I digress, how big is 11B tons of ice.
Using very straight forward math and a factor that a cubic foot of ice weighs 5.72 lbs, it easy to compute.
11B tons equates to 26.12 cubic miles lost in one day.
The surface area of Manhattan island is 22.8 sq miles, so the ice lost would be the area of Manhattan 1.15 high.
Feel free to check the math on your own.
Your math is wrong.
11B tons is 11Gt and equals 11cubic kilometers.
Even with 11Gt a day year round it would take more than 100.000 days to loose half the ice.
Joe, ice weighs 57.2 pounds per cubic foot, not 5.72.
w.
Thanks for the correction.
Your math is wrong.
11B tons is 11Gt and equals 11cubic kilometers.
Even with 11Gt a day year round it would take more than 100.000 days to loose half the ice.
Congratulations Willis, this article has made it to Breitbart, thanks to Dillingpole.
https://www.breitbart.com/politics/2019/08/04/delingpole-greenland-ice-melt-shock-the-terrifying-truth/
Thanks, Ben. Fame awaits me, I’m sure … that and $5 will get a cup of coffee at Starbucks …
Best to you,
w.
I really want to believe that you guys are on the correct side of this, because after 50 years of forecasting weather I don’t know.. I think you would sound more credible if something in the climate change ‘news’ frightened you guys a little.
meteorologist in research August 4, 2019 at 6:09 pm
Thanks, Meteo. What is it that you think we should be frightened of? The coral atolls are not disappearing. There’s been no increase in the rate of sea level rise. Just which phenomena do you think are outside of historical norms? We’re at the cold end of the Holocene. The recent warming has been going on for at least 200 years … so …
What are you afraid of? This climate has survived meteor strikes and volcanic eruptions, what is it that frightens you?
Serious question, thanks for your answer.
w.
Very good question Willis, I hope you get a good answer…but don’t see any extreme weather and SLR events that would frighten them. From observations/data, etc.
Thanks. This is a huge subject. After reading about the data you’ve shared it seems that it’s all natural fluctuations. The slight trends that can be found are all in the ‘bad’ direction as I see it, but there’s so much noise and we don’t have a good grasp of the subtle mechanisms so it shouldn’t be frightening yet. What will it look like in a few decades? I won’t be around to find out.
So the obvious question is what would cause you concern? Are we coming out of Holocene conditions too quickly to keep us complacent? Will more and more greenhouse gases change things? Will feedbacks finally have had enough time to take effect?
Are you watching the Rossby Wave pattern? It should affect regional climates more quickly than the slight warming you talk about. So far the amplification or the elongation of the long waves haven’t remained in an ‘abnormal’ pattern for long. I’m thinking this will be the first sign of changes, since those patterns form and sustain regional climates.
More immediately as it is now, we should be frightened about large flares, extinctions, clean water, meteors that surprise us and all the scarcities which might result from overpopulation.