Potsdam Institute Scientists - Expect 1-Meter Rise In Sea Levels By 2100 - ENN/DPA

[hatrack]

Berlin, Oct 9 (DPA) Global warming calculations have been too optimistic, and the sea level round the globe is likely to rise a full metre this century, two senior German scientists warned Wednesday.Hans Joachim Schellnhuber, who heads the Potsdam Institute for Research on Global Warming Effects and Jochem Marotzke, a leading meteorologist, said UN-backed data on climate change, predicting a rise of 18 to 59 centimetres, was out of date.

“We now have to expect that the sea level will rise by a metre this century,”� said Schellnhuber in Berlin.

He said international plans to limit the rise in average global temperatures to just 2 degrees Celsius by the end of the century, mainly by limiting growth in carbon dioxide emissions, were only achievable with enormous effort.

Schnellnhuber, who is official adviser to German Chancellor Angela Merkel on climate-change issues, said the new findings employed data unavailable to the Intergovernmental Panel on Climate Change (IPCC) for its most recent global warming report.

EDIT

http://www.enn.com/ecosystems/article/38375

[jdlh8894]

1. Damn, just Damn !!

In the last 100 years we have learned to contain the energy that the Earth provides us with and make our lives better.IMHO in the next 100,
we will see solutions. My children will make a difference. There are no
quick solutions.

[RaleighNCDUer]

2. Talk about too optimistic.

I would bet on a 1 meter rise by 2050. By 2100, 5 meters, minimum.

The arctic will be ice-free in summer within 10 years. This will exacerbate the melting of the Greenland ice sheet (another thread just today noted that the summer melting season had expanded by 18 days this year) and I would not be surprised to see the entire Greenland sheet disappear by 2050. As sea levels rise they will lift the leading edge of glaciers in the antarctic, speeding their collapse.

Not to mention, the warming of arctic waters will affect the permafrost adjacent to those waters, allowing the release of massive amounts of methane which is 20x the greenhouse gas that CO2 is.

Take the most pessimistic official report you can find and DOUBLE its predictions and you might start to get close.

Where we are today, ten years ago they said we would not reach until 2040.

[jdlh8894]

3. I'll take your bet in a heartbeat!

If the Gulf Stream gets warmer, that means it goes deeper.
Creating more space.

[Brush Fire]

5. "The arctic will be ice-free in summer within 10 years."

Are you serious?

[XemaSab]

6. It's entirely possible--nay, likely

[The Croquist]

4. If so we have allot of catching up to do

Sea Level is rising by about 3.1 mm per year. That works out to about a foot not 3.25 feet. Interestingly enough, The earth has averaged about 2.33 feet per century for the last 18,000 years.

Same old panic. Same old facts Hatrack.

[Barrett808]

7. That's the problem with averages...

...they can conceal a lot of detail in a signal.

Here's the estimated sea level for the past 24,000 years:





As you can see, the rate of sea level increase has been nearly flat for about the last 8,000 years, after a relatively rapid rise over the previous 10,000 years or so.

In a warming atmosphere, there's no reason to believe that the flat Holocene trend will continue; there's plenty of cryosphere yet to melt, snd it's melting very fast in some places.

[The Croquist]

8. I have a different tack on your point

Look at the different measurements on the chart. Some that are estimated to be the same age are many meters apart. There can be a few reasons:
One or more of the measurements is wrong.
The time on one or more is wrong.
There was a local geologic event that shifted the measurement point vertically after the date.

I will not disagree that in all likelihood sea level has risen slower in the last 8 thousand or so years then previously but that leads to the question of why did the rate of change, change so often in the past? There is a second question as well. How accurate would that data be over a period of years, decades or even centuries? Here is the third question. If sea level could rise in the past without mankind's help why is current sea level rise caused by mankind?

We have so little history of accurate data that drawing long term projections is little more then guessing. Here is what we do know:

In thirty or so years of satellite tracking we see the ocean rising at the rate of about a foot a century.
The IPCC predicts that sea level will rise between 0.6 and 2.0 feet "in the next century". I take that term to mean by 2108 not 2100.
The article Hatrack cited is predicting 3.25 feet (1 meter)this century. That means in the next 92 years.

Now the sea level rise may accelerate or not but the IPCC has left a significant range in their prediction. Frankly I'm not impressed with their prediction. It's like predicting that the average summer temperature in a location will be the same temperature as last year plus or minus 3 degrees. Chances are you will be right.

I am also not convinced that we are in a warming phase. The atmosphere has not warmed in the last 10 years. It is warmer then 30 years ago but as of now we peaked 10 years ago. Will warming start up again? I don't know but I would guess so. Would I bet on it? No.

[Barrett808]

9. We understand quite a lot about the sea level of paleo-oceans

A fascinating recent paper by Maureen Raymo, et al. is particularly informative:

Plio-Pleistocene ice volume, Antarctic climate, and the global δ¹⁸O record
M. E. Raymo, L. E. Lisiecki, Kerim H. Nisancioglu

We propose that from 3 to 1 million years ago, ice volume changes occurred in both the Northern and Southern Hemispheres, each controlled by local summer insolation. Because Earth's orbital precession is out of phase between hemispheres, 23,000-year changes in ice volume in each hemisphere cancel out in globally integrated proxies such as ocean ¹⁸O or sea level, leaving the in-phase obliquity (41,000 years) component of insolation to dominate those records. Only a modest ice mass change in Antarctica is required to effectively cancel out a much larger northern ice volume signal. At the mid-Pleistocene transition, we propose that marine-based ice sheet margins replaced terrestrial ice margins around the perimeter of East Antarctica, resulting in a shift to in-phase behavior of northern and southern ice sheets as well as the strengthening of 23,000-year cyclicity in the marine ¹⁸O record.

(more)

http://www.sciencemag.org/cgi/content/full/313/5786/492?ijkey=N9XCNeUK8XClg&keytype=ref&siteid=sci

Dr. Raymo models insolation and ice dynamics for the period from 3mybp to 1mybp and accurately predicts the observed ¹⁸O signal in ocean sediment cores:



Comparison of predicted mean ocean ¹⁸O and the LR04 stack


With this remarkable accomplishment, we have high confidence that we understand the dynamics of insolation, ice sheets, and sea level. This answers your first two questions.

As to your third question: If sea level could rise in the past without mankind's help why is current sea level rise caused by mankind?

Because we understand the dynamics, we can say with high confidence that in the absence of external forcings, the current (Holocene) interglacial should be ending about now, and we should observe a cooling trend.

Instead, we observe a warming trend. Something has perturbed the system and introduced an external forcing. That something is human carbon emissions.

As to your last questions: The atmosphere has not warmed in the last 10 years. It is warmer than 30 years ago but as of now we peaked 10 years ago.

In fact, it's not the case that global mean temperature has dropped since 1998; even over the short ten-year data set, the trend is upward. See Tamino's analysis:

It turns out that even if we start at the 1998 peak, the trend is still warming. This is true for both GISTEMP and HadCRU data, and both results are statistically significant. There’s no getting around it: the planet has continued warming overall, since the 1998 El Niño event. The fact that one of two data sets indicates we haven’t broken the 1998 record, doesn’t alter the fact that the trend is still hotter.

http://tamino.wordpress.com/2007/08/31/garbage-is-forever

So theory and observation match well. We understand the dynamics of paleoclimate and sea level, and we can predict with high confidence that sea level will rise significantly in the next century due to human intervention.

[The Croquist]

10. Always a pleasure, Barrett808

I'm sorry but I don't see how M. E. Raymo, L. E. Lisiecki, Kerim H. Nisancioglu answers my first two questions. The chart shows 2 million years of time, predicted values and "actual" measured values. Although the predicted and measured values tend to cycle together quite well, there is usually a significant variance between the two. I don't fault the study but it is simply a fact that measuring things from 3 million years ago is a challenging task. Maybe the measured data is wrong or maybe other factors are also significant.

You say that "the current (Holocene) interglacial should be ending about now" but in response I ask "how much is about? Was it supposed to start in the year 2000 plus or minus a year or plus or minus 1,000 years? I know that ice ages tend to cycle but how accurately can we predict when another one is due or more importantly, overdue? The Earth didn't used to have ice ages and one day it won't have them again, with or without mankind's help.

I completely disagree about the earth not cooling in the last 10 years. One difference is that I use satellite data while your numbers are using GISTEMP and Hadley. I don't trust the surface measurements.

Here are the satellite numbers:

1998 0.514
1999 0.041
2000 0.035
2001 0.198
2002 0.312
2003 0.275
2004 0.196
2005 0.339
2006 0.261
2007 0.282

2007 was .26 degrees cooler then 1998, 2006 was .34 degrees cooler. I know that 1999 - 2001 were even cooler but the fact remains that 1998 was the warmest year recorded by satellites.

2008 will in all likelihood be even cooler. These are the number for the first 9 months of these years.

1998 0.588
1999 0.047
2000 0.023
2001 0.176
2002 0.330
2003 0.241
2004 0.178
2005 0.332
2006 0.244
2007 0.315
2008 -0.002

So far 2008 is 0.59 degrees cooler then 1998.

Do you agree that a range of 0.6 and 2.0 feet leaves allot of wiggle room on the table?

[Barrett808]

11. As they say in data analysis: "All numbers are wrong"

The trick is in estimating how wrong. :)

Variations in the predictions for sea level rise don't bother me -- in fact, I expect them. I'm even a little surprised that the range of predictions is as constrained as it is.

I'd say the gold-standard estimate right now is in the recent paper by Pfeffer, et al.:

Kinematic Constraints on Glacier Contributions to 21st-Century Sea-Level Rise
W. T. Pfeffer, J. T. Harper, S. O'Neel

On the basis of climate modeling and analogies with past conditions, the potential for multimeter increases in sea level by the end of the 21st century has been proposed. We consider glaciological conditions required for large sea-level rise to occur by 2100 and conclude that increases in excess of 2 meters are physically untenable. We find that a total sea-level rise of about 2 meters by 2100 could occur under physically possible glaciological conditions but only if all variables are quickly accelerated to extremely high limits. More plausible but still accelerated conditions lead to total sea-level rise by 2100 of about 0.8 meter. These roughly constrained scenarios provide a "most likely" starting point for refinements in sea-level forecasts that include ice flow dynamics.

http://www.sciencemag.org/cgi/content/abstract/321/5894/1340

The good news is that a sea-level rise of greater than 2m is ruled out; the bad news is that the rise could be a great as 2m, which is higher than any serious climate researchers have suggested previously.

[The Croquist]

12. More plausible but still accelerated?

How likely is that? It sounds like they are talking about it possibly accelerating to between 0.8 meters (31 inches) and 2 meters (78 inches). That's an even bigger range then the IPCC.

It is currently rising at about 3.1 mm per year. That works out to about 11 inches by the year 2100. What if it doesn't accelerate?

I never heard As they say in data analysis: "All numbers are wrong" but it is something we can agree on.

[Barrett808]

13. Because I'm a pessimist, I assume all of these estimates are on the low side

Personally, I think the 21st-century changes in climate will be so cataclysmic that it won't matter whether sea level rises one meter or two (or five). Methane from clathrates is already bubbling up all over the Arctic Ocean, and tundra is melting throughout the Arctic. Those two observations by themselves essentially spell the end of the Cenozoic biosphere. Ocean acidification is accelerating geometrically, which basically guarantees the end of ocean ecosystems that have survived since the Paleocene-Eocene Thermal Maximum, 55 million years ago.

I hope I'm wrong, but I'm glad I don't have children.

[The Croquist]

14. I'm glad I don't have kids too.

I consider it my way of helping the gene pool.

Once again I disagree (what a surprise!).

Lets look back at the chart you sent out showing sea level rise over the last 22,000 or so years. I'm sure you agree that sea level and the retreat of the ice sheets are closely related. Starting at that point in time huge chunks of Asia, Europe and North America were covered with ice. As temperatures rose, the ice retreated, the ground and ocean floors warmed and should have released huge amounts of methane but life on earth didn't end. Instead it thrived. Now you can argue that it took place over a longer period but the fact of the matter is it appears to have happened in fits and spurts. If these methane releases didn't create a positive feedback back then why do you expect it to do so now?

I suspect that methane has been bubbling up from the oceans and being released from the tundra for thousands of years but nobody noticed until recently.

[Barrett808]

15. These kinds of feedbacks almost certainly do drive rapid deglaciations

The permafrost melts that we're seeing today may release hundreds of gigatons more carbon than during previous deglaciations. Which is to say, this permafrost has not melted in hundreds of thousands of years, and it will release gigatons of carbon that have been sequestered through several ice ages. See, for example:

Vulnerability of Permafrost Carbon to Climate Change: Implications for the Global Carbon Cycle
Edward A. G. Shuur, et al.

Thawing permafrost and the resulting microbial decomposition of previously frozen organic carbon (C) is one of the most significant potential feedbacks from terrestrial ecosystems to the atmosphere in a changing climate. In this article we present an overview of the global permafrost C pool and of the processes that might transfer this C into the atmosphere, as well as the associated ecosystem changes that occur with thawing. We show that accounting for C stored deep in the permafrost more than doubles previous high-latitude inventory estimates, with this new estimate equivalent to twice the atmospheric C pool. The thawing of permafrost with warming occurs both gradually and catastrophically, exposing organic C to microbial decomposition. Other aspects of ecosystem dynamics can be altered by climate change along with thawing permafrost, such as growing season length, plant growth rates and species composition, and ecosystem energy exchange. However, these processes do not appear to be able to compensate for C release from thawing permafrost, making it likely that the net effect of widespread permafrost thawing will be a positive feedback to a warming climate.

http://www.aibs.org/bioscience-press-releases/resources/Schuur.pdf

[Viking12]

16. Are you a cherry-picking liar or just ignorant.?

The last 10 years of satellite data, from October 1998 through September 2008:

UAH: +.0.11 deg.C/decade

http://tamino.wordpress.com/2008/10/14/bjorn-lomborg-how-did-you-get-those-numbers/#more-1116

[Barrett808]

17. I'd characterize him as "naive"

But The Croq seems willing to learn, so I give him the benefit of the doubt.

[Viking12]

18. No he's not willing to learn.

He's played the "global warming stopped in 1998" card before and been shown that is is a load of crap, yet continues to play it. Add to that bullshit like, "I don't accept GISS" and you get a pretty clear picture that he's not willing to learn. He's a denier troll.

[Barrett808]

19. I won't go very far out of my way to defend him, and I wish he'd study some actual climate science

And wean himself from ClimateAudit...

[The Croquist]

30. I read a variety of sources

Real Climate doesn't post as often as Climate Audit but Steve McIntyre can be painful to try and understand. I just don't have the statistical knowledge to follow most of his arguments. Both sites tend to get in personal grudge matches with the opposition especially McIntyre on Mann.

One reason I enjoy Anthony Watts is he is less antagonistic then others. He is also willing to post different opinions. He recently posted a question and answer session from Walter Meier of NSIDC on Arctic ice. It disagrees with what is the position of Anthony Watts but he is willing to post it none the less. It is also quite civil in nature by both sides (I haven't read the comments).

If Meier is trying to educate people he is doing it the right way.

[Barrett808]

33. Set aside the climate issue: how about ocean acidification?

Surely you don't dispute that human carbon emissions are causing enormous, deleterious changes in ocean chemistry.

[The Croquist]

20. It is a fact that the warmest year in the short 30 history of satellite measurements was 1998

I do not dispute that the earth was warmer in 2007 then 1979. I don't even dispute that the trend has been up for the last 30 years although the last 9 of those years have not supported that. I don't even dispute that the earth maybe heading to a period of ecological disaster caused by man made global warming.

Here is what I dispute:
The claims of certainty.
The claims that disaster is right around the corner.
The claims that it is already too late or that if we don't stop it now it will be too late.
The claims that anyone who disagrees is either paid by the oil companies, cherry picking data or a liar.

Here is what bothers me:
Panic mongering by believers in AGW to support their claims. If they could stand on their own merits panic mongering wouldn't be needed.
Being called an advocate for murdering millions or billions of people because I think the third world needs to stop growing it's population and preferably reverse it.

Here is what I think we know about what is going on:
Not much. We are learning but we have along way to go before we really understand what is happening. Learning is good but I wouldn't trust a kindergarten kid to tune up my car and our knowledge of climate is closer to kindergarten then to Mr. Goodwrench.

Keep in mind that this post started off about new estimates that sea level rise will be about 1 meter instead of the IPCC estimate of 18 to 59 centimeters. I pointed out that at the current rate it would increase about 31 centimeters. That is within the IPCC guidelines but below the article posted.

I would love to discuss why I don't trust GISS if you would like.

[Viking12]

21. I've heard it. You saw some pictures on some idiot's blog.

Again, you make false claims about the temperature trend of the last decade. You're wrong even when we use the temperature data of your choice.

The claims do stand on their own. That you don't have the capability to comprehend them, doesn't make them go away.

[The Croquist]

22. I saw hundreds of pictures on Anthony Watts blog

Just because you disagree doesn't make him an idiot.

[Barrett808]

24. Is Mr. Watts's work peer-reviewed and published?

If not, why would you prefer his opinion over that of published researchers?

[The Croquist]

26. No Watts work is not peer reviewed

and some of the site analysis is less then thorough. Frankly some is shoddy but he is doing his best with limited resources. I could give a few examples if you would like but he has provided a service that apparently no one else has been doing and without federal grants. He is documenting the quality of the surface stations done by the scientific community. Some are good but too many are unacceptably bad. What I would love to see is a published report to rate the quality of the stations. If any have been done I am not aware of it. Instead of attacking him as an "idiot" (not you Barrett808) we should be demanding that a report be done. He has shown station after station that fail to meet minimum criteria. Perhaps he is not publishing the stations that pass muster but I doubt it.

Would it be too much to ask for some undergrads or grad students to go out there and take some pictures, measurements and file reports? Lend them a camera, give them some gas money and call in a lab credit. It might teach them something about the real world.

That leads us to a second issue: If the station quality sucks today (and I think it does) what was it like 20 years ago? How about 50, 75, 100 years ago? If we don't know what they are like today how would we know what they were like in the past?

Data from these stations are adjusted for external influences but without knowing what is influencing a station how do you know how much to adjust the data? Even if you do know what is influencing a station wouldn't it be better to improve the station siting rather then have to adjust the data?

It's not that I prefer his opinion but his work raises questions that should be addressed by other means then by insulting him and ignoring his work.

[Barrett808]

34. Why would you prefer the ideas of a lone dilettante over the scientific, peer-reviewed literature?

Are there any other sciences against which you have this bias? Perhaps you prefer the ideas of the Discovery Institute over those of evolutionary biologists? Or maybe you prefer Bjorn Lomborg's claims that the current mass extinction of species is nothing to worry about, over the opinions of biologists like E.O. Wilson?

[Viking12]

25. You've reveresed causation. I disagree with Watts because he is an idiot.

[The Croquist]

29. So why is he an idiot?

PS: Even idiots can be right sometimes.

[Viking12]

31. If you have to ask....

http://tamino.wordpress.com/2008/03/02/whats-up-with-that/

http://tamino.wordpress.com/2008/03/27/how-not-to-analyze-data-part-1/

http://tamino.wordpress.com/2008/03/30/how-not-to-analyze-data-part-deux/

http://tamino.wordpress.com/2008/04/01/how-not-to-analyze-data-part-3/

http://tamino.wordpress.com/2008/04/07/how-not-to-analyze-data-part-4-lies-damned-lies-and-anthony-watts/

http://tamino.wordpress.com/2008/02/03/exclamation-points/

Bottom line = Wats is an idiot, as are those that put any credence in what he has to say.

[Barrett808]

23. Do you dispute the radiation physics?

Before you dispute the other aspects of climate science, you should examine your opinions on the basic physics.

Do you dispute the established radiation physics of greenhouse gases? As a corollary, do you dispute the central role played by CO₂ in regulating Earth's climate?

[The Croquist]

28. CO2 certainly regulates the Earth's climate

and it is important but so are many other factors. Obviously the Sun is number one (no I'm not blaming warming temperatures on the sun) as does H2O.

I'm not even sure that it is number three in the long run but probably currently running number one or two (to H2O). But having said that, I question how big the natural fluctuation is compared to CO2 forcing.

[Barrett808]

32. I assure you, the natural fluctuation is small compared to the CO2 forcing

Why wouldn't dumping hundreds of gigatons of carbon into the atmosphere have profound effects on climate and ocean chemistry?

[The Croquist]

27. I recently learned allot about the Albedo effect on Venus and Mars.

That was not only educational but humbling.