Guest post by David Middleton
Sea levels could rise far more rapidly than expected in coming decades, according to new research that reveals Antarctica’s vast ice cap is less stable than previously thought.
The UN’s climate science body had predicted up to a metre of sea level rise this century – but it did not anticipate any significant contribution from Antarctica, where increasing snowfall was expected to keep the ice sheet in balance.
According a study, published in the journal Nature, collapsing Antarctic ice sheets are expected to double sea-level rise to two metres by 2100, if carbon emissions are not cut.
Previously, only the passive melting of Antarctic ice by warmer air and seawater was considered but the new work added active processes, such as the disintegration of huge ice cliffs.
“This [doubling] could spell disaster for many low-lying cities,” said Prof Robert DeConto, at the University of Massachusetts Amherst, who led the work. He said that if global warming was not halted, the rate of sea-level rise would change from millimetres per year to centimetres a year. “At that point it becomes about retreat [from cities], not engineering of defences.”
[…]
I don’t know if Mr. Carrington has poor math, poor reading skills or is just inclined to hype his stories. The “study, published in the journal Nature,” is actually an interesting paper and the full text is available for reading, but not downloading. The authors devised a model which couples Antarctic ice loss to past sea level rises in the Pliocene and Pleistocene. They then used this model, coupled with “Representative Carbon Pathway (RCP)” scenarios to forecast future sea level rises.
DeConto and Pollard conclude that “Antarctica has the potential to contribute more than a metre of sea-level rise by 2100.”
Mr. Carrington apparently added this 1 meter to the IPCC’s 1 meter to come up with 2 meters. He even bastardized a quote from Dr. DeConto…
“This [doubling] could spell disaster for many low-lying cities.”
The word “doubling” is Carrington’s, not DeConto’s.
I don’t know if Mr. Carrington read the paper or not; however the authors never forecasted a sea level rise of 2 meters by 2100…
The IPCC sea level forecast for 2100 in RCP 8.5 with ice-sheet rapid dynamics is 0.74 m (0.52 to 0.98 m), not 1 meter. The Antarctic contribution is 0.04 m (-0.06 to 0.12).
If we go with the most likely, worst case RCP 8.5 scenarios…
IPCC – Antarctica = 0.70 m
DP 2016 Antarctica = 1.05 m
Sum =1.75 m
Under this scenario, the Antarctic contribution would actually more than double the IPCC’s forecast… But it would still be less than 2 m.
Now, let’s have a look at RCP 8.5…
This noachian deluge forecast is based on the assumption that the atmospheric CO2 concentration will rise to 1,120 ppm by 2100
Does anyone actually believe that humans could burn enough stuff over the next 84 years to drive CO2 levels up by 700 ppm above the current ~400 ppm? CO2 would have to rise by an average of 8.33 ppm per year over the remainder of the 21st century.
It appears that RCP 8.5 will turn Earth into Venus by 2100 AD.
But, what happens if I use real data?
Let’s assume that the atmospheric CO2 level will rise along an exponential trend line until 2100.
I get a CO2 level of 560 ppmv, in line with RCP 4.5… which leads to 0.53 (± 0.18) meters of sea level rise by 2100.
The only way sea level rise could approach the high end of the IPCC range is if it exponentially accelerates…
The rate from 2081-2100 would have to average 20 mm per year, twice that of the Holocene Transgression. This is only possible in bad science fiction movies in which Earth turns into Venus by 2100.
There simply is no data- or observation-driven reason to conclude that sea level will rise by more than 0.16 to 0.28 m (7-11 inches) during the 21st century under a realistic “business as usual” Representative Carbon Pathway.
Addendum
RCP 8.5 is even more batschist crazy then I had assumed…
Yep, and I could fly to the moon with rocket smoke coming out of my butt. I have a detailed model, so it must be so.
So at between 1-3mm/yr and no real sign of acceleration, how, pray tell is this gonna happen?
Easy… Just change “has the potential to” into “is expected to.”
give me a break Shakespeare had these climate charlatans rightly placed around the big kettle;
double, double, toil and trouble
the climate burns as environmentalists bubble
..I find it amazing that the liberal left can not even consider the possibility that the temperatures may reverse, as in the past, and become uncomfortably COLD ! As a Canadian, I can tell you, personally, that would really suck !
Marcus, what you suggest is flat out impossible, as it would require a warmista to have an independent or original thought, or, even more unlikely engage tin critical thinking.
I suspect Dontgetoutmuch will be sending us stinky green smoke signals from the moon before either of those things occur.
As a Canadian, it already sucks. Snow is forecast for this Sunday (Toronto) and well below average (current high about 8°C) temperatures for the next week at least.
“At that point it becomes about retreat [from cities], not engineering of defences.”
hahaha … tell it to Venice, they’ve made a fortune out of it.
The Dutch have held back a rising ocean since Medieval times using hand tools and simple machines powered by the wind.
But the fact is that the ocean is showing no sign of an acceleration in the gradual rise it has been undergoing for well over a hundred year.
At the current rate, all that would be necessary to avoid problems far into the future is to stop rebuilding in places destroyed by coastal storms and hurricanes.
The Guardian apparently exists to make the New York Times climate reporters look good. The new motto should be POOMA for sources.
Thanks, Tom. Took me a minute to understand. Pulled Out Of My ___.
A ubiquitous source, all right.
Dan
Just published!!!!! This epic paper (which misses, entirely, ENSO processes that could exhibit a long term imbalance swing that results in rapid rise with jagged fall) attempts to describe the past 800,000 years of global warm and cold periods. Read in chunks. Lots to digest. This paper will be used by many in their attempt to ascribe CO2 as the driver. Only discerning researchers will ponder oceans as a long term battery combined with a long term oscillation that provides the energy necessary to drive the swings that supplies the stored energy that keeps things moving.
http://onlinelibrary.wiley.com/doi/10.1002/2015RG000482/full
Here is the thing folks. Researchers want to find some sexy, magical tiny driver that in turns moves mountains. But what drives small swings should be our first consideration as a driver of large swings. That said, this paper is a garden of delights.
I love the hyperbolic title. I bet the first draft said… ‘Sea level expected to rise more than previously expected’
On the upside, wouldn’t this be good for the fishing industry? Try to think positive thoughts.
Here’s what the rate of sea level rise has done since 2006 according to the current data
http://sealevel.colorado.edu/files/2016_rel1/sl_ns_global.txt
kept by the University of Colorado’s Sea Level Research Group:
http://oi63.tinypic.com/2vinjnd.jpg
It’s just a question of whether or not you think the uptick since 2012 will continue on into the future
Nice try Steve , plotting graph upside down, April 1st.
2014 followed 2014, it’s Deja vu all over again!
That graph needs uncertainty values or 90% confidence intervals. But it also lacks any serious quality control.
As in, they determined 2014 Global SLR was 0.04 mm/yr (40 microns) higher than end of 2012. Yeah right.
Two 2014s
Ha ha ha ha ha ha ha ha ha!
Missed that one. The time line intervals of CU’s data are tied to the satellite orbits, and in order to make it come out right you have to, among other things, well look to see if it did. Here’s one I did earlier with 100 day smoothing:
http://oi65.tinypic.com/29549l0.jpg
I used the half way point of the time series (2004) instead of the last decade. I couldn’t decide. Maybe I should do it again and start at 2000. Doesn’t matter, calculating the rate 1992-1993, 1992-1994, 1992-1995, etc. and plotting the result starting at some reasonable point 1992-2000, or 1992-2004, or 1992-2006 to eliminate the effects of short term noise will produce similar graphs.
Thanks for pointing out the error
Well, first it’s a question of whether you believe they can actually measure sea level rise with the accuracy implied by the graph. Am I correct in my understanding they claim to have been able to measure a 0.15 mm rise in world wide sea level between 2012 and today? Any realistic margins of error to be attached to these measurements?
Bullshit with no context.
http://s27.postimg.org/cjnmllofl/SLS_NS.png
Sea level rise and global warming
2014 followed by 2015 and now 2016 (based on the data recorded during the first quartile) are by far warmest years on record, mainly due to the temperatures rise in the N. Hemisphere. Well known climate scientist W. Civeckuv has found the true reason for the unprecedented warming.
Rapid rise of temperatures in the Arctic have led to record ice melting in Greenland, resulting in the melt water flowing further south, and so caused change in the global gravity (weight) distribution has affected the Earth’s rotation axis tilt.
The effect is progressively increasing N. Hemisphere’s and reducing S. Hemisphere’s insolation causing notable increase in the ice volumes in the Antarctica, and so further adding to the gravitational imbalance between hemispheres.
W. Civeckuv claims that the Earth’s climate has entered dangerous ‘positive feedback loop’, and recovery may not be possible at least for another 100 kY, when the next but one Milankovic cycle is about to kick in. more details can be found here
April 1st 2016
Yes it is 1st April story, but not necessarily totally implausible.
W. Civeckuv = M. Vukcevic (wrong way around), the link is to my website. Hope no one is offended.
We appreciate the effort.
Actually, in all seriousness, I have wondered whether such a thing is possible. Consider that all of the ice locked up at the poles is sitting on or near the Earth’s axis of rotation, and therefore has a small amount of angular momentum. Imagine that if all the ice melts and flows into the oceans, it will gain momentum as it flows towards the equator. However, more of the melt water, and therefore more of the momentum, will end up in the southern hemisphere as we have noted the northern hemisphere is already filled with most of the water displacing continental crust. So now that we have further unbalanced from north to south the spinning Earth, which already has known wobble, what happens to that wobble?
But then again, I have also wondered what the collective effect would be on all of the Earth’s seismometers would be if we all jumped up off the ground at exactly the same time. Should we try it? How about next year, April 1st, 2017, 12:00 GMT? I can see the headlines now … Ground-breaking flash mob shakes the world!
Hi Mr. Edwardson, thanks for the comment. I suppose a good April 1st story has to be just on the edge of credibility.
Wait I’ve seen this story before haven’t I? Or no it’s just that they are always predicting a meter sea level rise over the NEXT century. Mind you the start and end dates of that century keep moving forward and we never seem to actually be in the century where it is happening when you go back and look.
There’s not a lot of difference between averaging 10 mm/yr for the next century or 12 mm/yr for the next 84 years. Both are gross exaggerations.
I know and worse they recycle it every single year and no one but us skeptics questions it. ::sigh:: you would think someone would eventually suffer enough cognitive dissonance from the sea levels not actually rising that fast.
I remember reading somewhere that to reach the CO2 levels involved in RCP 8.5 we would have to dig up and burn every single bit of fossil fuel on the planet over the next 84 years.
Then we would have to dig it all up and burn it again.
5 times over
Anyone know if this is accurate?
For some reason, I think I recall that the burning of all of the coal, oil and natural gas resources believed to exist in the Earth, would release about 5,000 ppm worth of CO2. I’m not sure if that’s accurate.
Let’s see what would happen if the US proved coal reserves went up in smoke…
“As of January 1, 2015, the demonstrated reserve base (DRB) was estimated to contain 478 billion short tons.”
http://www.eia.gov/coal/reserves/
“1 short ton (2,000 pounds) of this coal will generate about 5,720 pounds (2.86 short tons) of carbon dioxide.”
http://www.eia.gov/coal/production/quarterly/co2_article/co2.html
478 billion short tons of coal would yield 1,367 billion short tons of CO2 (373 billion short tons of carbon or 338 GtC).
“Using 5.137 x 1018 kg as the mass of the atmosphere (Trenberth, 1981 JGR 86:5238-46), 1 ppmv of CO2= 2.13 Gt of carbon.”
http://cdiac.ornl.gov/pns/faq.html
338 GtC / 2.13 GtC/ppm = 159 ppm
RCP 8.5 has more CO2 than would be generated by burning all current reserves.
Doing the calculation on RCP8.5 shows burning more coal than there is reserves, by 2100.
Reserves 860 Gt
http://en.wikipedia.org/wiki/Coal
the paper that shows the amount of coal burned in exaJoules. (10^18 joules) Fig 5 (need to estimate from graph. I get 40000 EJ over the century)
http://download.springer.com/static/pdf/700/art%253A10.1007%252Fs10584-011-0149-y.pdf?auth66=1411082238_6e5e56fcca0686fcc271b84fd0868908&ext=.pdf
energy in coal (7.2 GJ for 1 tonne to make electricity this gives 6.19E^21 J total energy in 860 GT reserves)
http://hypertextbook.com/facts/2006/LunChen.shtml
Total reserves vs amount burned in this scenario is about 15.5%, or 6.5 times more coal than in reserves. In other words, not possible. If you increase the energy in coal from 7.2 GJ/tonne to about 20, then total burned in RCP8.5 is only about twice reserves. Which is still impossible. There can be up to 30 GJ/tonne energy in coal. Even at the upper end, there is still more coal burned than there is reserves.
This was also calculated here, with similar results.
http://judithcurry.com/2014/04/22/coal-and-the-ipcc/#more-15332
Time to act. Start tearing down all the seaside homes while they are in tact. Much easier to clean up now before they are washed to sea.
I stopped taking this seriously when I got here … “This noachian deluge forecast is based on the assumption that the atmospheric CO2 concentration will rise to 1,120 ppm by 2100”
Didn’t Willis, or one of the normal contributors here, figure out that there’s not enough available carbon reserves in the entire world to double CO2 from 400ppm to 800ppm?
If you burned all of the proved coal reserves of the US, you would generate about 159 ppm CO2. If all of the world’s proved reserves of fossil fuels were suddenly burned, you might have enough to hit the noachian CO2 levels.
That assumes that none of the CO2 that is sequestered during that 84 year period.
That’s just how much would be generated. Not how much would hang around in the atmosphere. About half of it would be naturally sequestered.
Also, Hansen forecast apologists (1988) always claim that “Scenario A” did not occur and it was between “B” and “C”. This is, of course, baloney. The business as usual Scenario A is what happened, and then some. Actually Scenario A+ is what happened. But, CO2 levels in the atmosphere did not rise as fast as Hansen thought. Conclusion… CO2 is accumulating in the atmosphere less than thought.
So, the atmosphere is less sensitive to CO2 than assumed and CO2 is accumulating in the atmosphere less than assumed. The result? Warming at about 40% of the rates forecast by models over the last 25 years. That is very good news. We don’t seem to have enough carbon burning capability to do much significant climate changing.
And sea level rates are the same or slower than ever….
http://www.jcronline.org/doi/abs/10.2112/JCOASTRES-D-10-00157.1
http://www.sciencedirect.com/science/article/pii/S0921818113002397
The “save the earth” types should be celebrating this news. Why, instead, are they so mad about it?
Thank you for coming to the same conclusion I came to, that sea level would have to accelerate at 3.7% per year, which would mean in the last years to 2100 it would have to be rising at some 25-30 times today’s rate. Physically impossible.
Maybe some of the meltwater pulses during the Holocene Transgression might have briefly hit 20 mm/yr. However, the average rate during the last deglaciation was about 10 mm/yr…
And that is where there was a whole lot more ice.
A *whole* lot more ice… I wonder if I could use the Hubbert equation and the volume of ice at the Last Glacial Maximum to calculate a “peak sea level” rate.
Sir, in regards to the insurance policy that said we would cover you for a runaway bulldozer smashing into your house for a mere $1,000 a month (minus a $5,000 deductible, of course, those office towers don’t build themselves):
We have unfortunately discovered that, in fact, you are in danger of TWO bulldozers smashing into your house. Your premiums will now need to be adjusted to $10,000 a month, and your deductible will now be $10,000, but please check back often, as the number of potential runaway bulldozers seems to be increasing exponentially, as our models show (spreadsheet attached).
Sir:
Our apologies, please delete the spreadsheet previously attached, as it was sent erroneously. Please note also that the title “Profit from Highly Dubious Insurance Outcomes” is also erroneous. As is the actual data. Please, please delete it. Its a draft, created by a now-terminated inexperienced employee.
This noachian deluge forecast is based on the assumption that the atmospheric CO2 concentration will rise to 1,120 ppm by 2100
As the graph states, this is a CO2-equivalent concentration. The year 2100 CO2 concentration in RCP8.5 is 936ppm.
Let’s assume that the atmospheric CO2 level will rise along an exponential trend line until 2100… I get a CO2 level of 560 ppmv
2015 level was 400ppm, so thats a 160ppm rise over 85 years = average rate of 1.88ppm/yr. That’s less than the average rate for the past 20 years, which suggests your exponential fit has gone wrong.
936ppm at 2100 means an average increase of 6.3ppm/yr. The current rate of about 2.3ppm/yr is roughly treble what it was 60 years ago so, from a basic demand economics perspective, I can’t see that a rise to 6.3 and beyond is implausible.
Exponential and power function trend lines applied to MLO…
A polynomial fit only pushes it up to the mid-600’s.
Extrapolating polynomials is generally a very, very bad idea!
Not even the bad idea leads to 900+ ppm by 2100.
And they publish this garbage as the Surface Mass Balance of Greenland is above the mean and that at Antarctica has been growing over all.
‘DeConto and Pollard conclude that “Antarctica has the potential to contribute more than a metre of sea-level rise by 2100.”’
The absurdity is glaring.
If it’s hot enough for the Antarctic to melt down just enough for a 1m SL rise, then it’d be hot enough for Greenland’s ice to melt more, and the Arctic ice, so the net overall supposed SL rise would be much greater IF they are right about CO2.
Did they figure out whether the predicted melting would occur under the ice or from the surface? In either case, what air/water temperatures did they assign to the Antarctic in order to drive the melting, and how did they figure that out? It’s pretty cold there now. How do they propose the temperature is going to get above freezing anywhere long enough there to melt that ice, and did they show that it happened before?
They showed that it *could* have happened during the Mid-Pliocene Warm Period and the Sangamonian (Eemian) Interglacial Stage. Those were periods in which the climate was considerably warmer and sea level was considerably higher than the present day.
The assumed Antarctic contribution to those high sea levels is based on their model. That’s why they said, “Antarctica has the potential to contribute more than a metre of sea-level rise by 2100,” rather than, “collapsing Antarctic ice sheets are expected to double sea-level rise to two metres by 2100, if carbon emissions are not cut.”
Models provide insight into what might happen under specific conditions.
I would argue that models provide no insight at all. Time after time they continue to fail in their predictions and attempts to capture the real world. They are expensive worthless computer games.
I agree… When the models are used as forecasting tools or treated like observations and real data.
Models are just tools. Any tool can be misused.
So David, help me understand what you are saying. Of what use are these models? I can model what would happen if we had a 10C rise in world temperatures by 2100 – so what? A model is only useful if it helps you to understand, and thus predict, a process and its real world results. Otherwise it’s either a game or a basis to commit a fraud.
I think the authors of the paper were just exploring the possibility that the warmth of those two periods could have triggered a meltwater pulse from Antarctica and led to a rapid rise in sea level. Then they looked at the possibility of a Venusian Representative Carbon Pathway triggering a similar event in the near future.
The thing about academic science is that it doesn’t actually have to serve a purpose… other than learning. Models are great heuristic tools.
The problem occurs when journalists and politicians assume that those models are real data.
Except it IS serving a purpose, for government to use as a tool to further their political agendas claiming the science says so. This BS about “might” is just that. I “might” get hit by a car today, but what are the odds? Not once have I see anything resembling any kind of odds, calculated or pulled out of the air. For if they did provide odds, their entire premise of humans causing catastrophic climate change completely collapses.
I like to use cities on tectonic zones. There “might” be an big one which would kill millions, yet noting is done to move people away from tectonic zones. Yet in climate science a “might” is used to justify raping people for billions in tax dollars.
This isnt about science at all, it is a means to an end of UN Agenda 21 and must be resisted.
Mr. Wakefield, you are 100% correct in your assessment of many government officials. They treat these sorts of studies as policy justifications and clearly most journalists participate in this process.
As a scientist, I just find it hard to believe that many scientists would intentionally publish dubious conclusions solely for political purposes. I don’t think Mann, Trenberth, Karl, Dessler, etc. are the norm. I do think that most of these scientists are just “tunnel-visioned” by a very flawed paradigm.
The monotonous uniformity of alarmist writings used to be an irritation. Now it’s a full-blown bore. Like The usual Obama speech, where his head bobs from side to side, punctuated with pregnant pauses as Soros gropes for the right string to pull, “Climate change is real…………….it is happening now……………more extreme weather……….more heat waves………..more intense storms……….right now millions are feeling the effects……of rising seas………….” and now we have that crosseyed chimpanzee from Ottawa reciting the same groan and moan. What to do.
Ha ha! I pointed this out 2 days ago.
http://wattsupwiththat.com/2016/03/30/oh-noes-model-says-sea-level-rise-from-antarctic-ice-sheet-could-double/#comment-2178632
The Grauniad article is about the same paper Anthony’s post was about. I missed that post entirely.
This post by Pat Michaels and Chip Knappenberger is also about the DeConto and Pollard paper…
http://wattsupwiththat.com/2016/03/31/deconto-and-pollard-an-antarctic-science-fiction-disaster-2/
I need to spend more time reading Watts Up With That… 😉
OMG!! A new hockey stick!
Is this the next “Carrington Event”?
“Oh we do like to buy beside the seaside”
Despite Climate Change . What are Coastal front property prices doing
Well, my benchmark on ocean-front property will be when Al Gore and David Suzuki (or more probably, their ancestors) sell. Until then, all is well.
http://www.independent.ie/life/motoring/oh-we-do-like-to-buy-beside-the-seaside-25979576.html
Heres that trumpetter of Climate doom to prove the point
David Middleton said:
“Models are just tools. Any tool can be misused.”
Climate models are the scientific equivalent of hitting your thumb with a hammer.