Climate

Scientists withdraw low-ball estimate of sea level rise — media are confused and anti-science crowd pounces

Projected sea level rise

The 2007 IPCC Fourth Assessment Report (AR4) report ignored dynamic ice-sheet disintegration, which was already happening (see Nature: “Dynamic thinning of Greenland and Antarctic ice-sheet ocean margins is more sensitive, pervasive, enduring and important than previously realized”).  The IPCC therefore low-balled sea level rise estimates, suggesting seas might rise “only” a foot or two this century, greatly delighting the anti-science crowd (see “Debunking Bj¸rn Lomborg:  Misrepresenting Sea Level Rise“).

Within a year, even a major report signed off on by the Bush administration itself was forced to concede that the IPCC numbers were simply too out of date to be quoted anymore (see US Geological Survey stunner: Sea-level rise in 2100 will likely “substantially exceed” IPCC projections).  About half a dozen major studies since the IPCC report concluded that we face much higher sea level rise this century (see “PNAS Study:  Sea levels may rise 3 times faster than IPCC estimated, could hit 6 feet by 2100” and links therein).

The figure above from the PNAS study is especially alarming since we are currently on the A1F1 emissions trajectory (see “U.S. media largely ignores latest warning from climate scientists: “Recent observations confirm “¦ the worst-case IPCC scenario trajectories (or even worse) are being realised” “” 1000 ppm“).  In short, we appear to be on track for 1.4 meters (56 inches) of sea level rise.

So the anti-science crowd was delighted when a Nature Geoscience study suggested that the IPCC estimates might not be so far off.  The top anti-science website, WattsUpWithThat, cheered, “Sea level rise by 2100, “nailed”! Between 7 and 82 centimeters” (3 to 32 inches).  At the time RealClimate scientists explained why the study was flawed.

Well, it turns out that the RC scientists were right — but the anti-science crowd is now cheering the withdrawal of the paper!  Brad Johnson explains how that could be:

What follows is a Wonk Room repost.

Scientists who challenged the possibility of catastrophic sea level rise in coming decades have retracted their argument. Mark Siddall, whose paper claimed sea level rise from global warming could not be more than 82 centimeters (32 inches) by 2100 “” despite other estimates of up to 1.9 meters “” asked for the conclusions published in 2009 in Nature Geoscience to be retracted, accepting corrections from researchers who had made the higher estimates. The Guardian misleadingly presented the news with the headline, “Climate scientists withdraw journal claims of rising sea levels“:

Study claimed in 2009 that sea levels would rise by up to 82cm by the end of century – but the report’s author now says true estimate is still unknown.

If all one read was the introduction, a reader might get the false impression that sea level rise from global warming is in doubt. The misleading Guardian headline was picked up “” as per usual “” by the Drudge Report and Marc Morano’s conspiracy site Climate Depot. Right-wing bloggers, unsurprisingly, latched on to the headline without any comprehension of the story:

Betsy Newmark: Another global warming claim that has had to be retracted because of problems with the data.

Sammy Benoit: OOPS Never-mind! Climate scientists withdraw IPCC-related article claiming sea is rising.

JammieWearingFool: Another global warming myth comes crashing down. No warming since at least 1995, no melting glaciers and now no rising sea levels.

Jules Crittenden: Warmal scientists are compelled to admit (again) that they don’t know what they’re talking about, retract study that predicted up to a nearly three-foot sea level rise by 2100.

Law professor William A. Jacobson: But now the seas are not going to rise? My dream of a waterfront home is melting away faster than the glaciers.

Caleb Howe: Yet another card removed from the geodesic dome of cards that is AGW hysteria.

However, the retraction instead admits that the paper’s calculations for an upper bound to future sea level rise were incorrect, and sea level rise could be much worse. Siddall’s study, “Constraints on future sea-level rise from past sea-level change,” used paleoclimate reconstructions to predict that sea level rise from global warming would be constrained to between 7 cm and 82 cm (3 to 32 in) by the end of the century, in line with the estimated sea level rise in the 2007 Intergovernmental Panel on Climate Change (IPCC) report, which excluded possible effects from ice sheets.

Unfortunately for the future of human civilization, the best scientific estimates of future sea level rise continue to worsen, as it becomes evident that the Greenland and Antarctic ice sheets are losing mass much more rapidly than estimated before 2007. December’s “Global sea level linked to global temperature,” published by Martin Vermeer of the Helsinki University of Technology, Finland and Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research in Germany in Proceedings of the National Academy of Sciences projects a catastrophic rise of 0.75 to 1.9 m (2.5 to 6 feet) by 2100 (see figure above).

Over the past twenty years, actual sea level rise has been at the top of estimated limits since the first IPCC report in 1990. By 2200, scientists warn, the oceans could rise by more than three meters, submerging cities like Los Angeles, Amsterdam, St. Petersburg, and lower Manhattan.

JR:  Another dreadful media headline, another round of anti-science confusion.  WhiskeyFire exclaims, “This is getting monotonous.”

Related Posts:

Tags

40 Responses to Scientists withdraw low-ball estimate of sea level rise — media are confused and anti-science crowd pounces

  1. dhogaza says:

    Glad you’re on this one, I’ve been fighting it on a variety of blogs. It’s amazing, the echo-chamber’s cheering over an own goal. Dudes and dudettes – the *denialist* goal is at the *other* end of the field!

  2. Wit's End says:

    Following is a copy of my comments – and the important one – from a certain Martin Vermeer, whom, I now revere:

    “That RealClimate post was about media attacking the credibility of scientists, and distorting their results, to which I commented:

    I blame John Edwards. The tabloids exposed his tawdry affair, thus, junk news sources gained credibility. That, and the fact that scientists are too timid about publicizing and linking current effects of AGW.

    Scientists should be on the teevee news every night with pictures of cow carcasses from the drought in Argentina, bleached coral reefs and dead sea beds, wildfires in Australia and California, collapsing ice shelves, melting ice caps with stranded walruses and penguins, shrinking glaciers and pictures of the people that need them for water, record breaking precipitation events like blizzards, droughts, and tornadoes in cities. Throw in some footage of scalped mountain tops in Appalachia.

    THAT should be the news, not made-up controversies. Forget your rectitude, scientists, step up to the plate! A habitable climate for YOUR children is at stake!

    Comment by Gail — 17 February 2010 @ 7:24 AM

    To which some actual scientist replied – and I do not know whether he meant to convey exasperation towards me or towards the constraint upon scientific speech, with his sigh:

    > Forget your rectitude, scientists, step up to the plate!

    Gail, that works only once. Our rectitude is our only weapon. Sigh.

    Comment by Martin Vermeer — 17 February 2010 @ 10:53 AM

  3. David B. Benson says:

    How many meters SLR before Foggy Bottom becomes Soggy Bottom?

  4. Craig says:

    You got to be kidding me. Let me see if I have this right. The anti-science echo chamber is at full decibel because sea level rises are predicted to be much HIGHER than previously thought.

    To all the bloggers (scientists and non-scientists alike) who are trying to beat back this wave of insanity and ignorance, my deepest thanks. You should be proud of the work you are doing.

  5. Wow! Just wow! I really cannot think of anything else to say…..

  6. MarkB says:

    Notice how this note is buried at the end of the article:

    “In the Nature Geoscience retraction, in which Siddall and his colleagues explain their errors, Vermeer and Rahmstorf are thanked for “bringing these issues to our attention”.”

    The Guardian title and intro is misleading and prone to denialist spin. This seems to be a common theme. It seems media sources are looking to attract hits from denialist websites.

    http://initforthegold.blogspot.com/2010/02/misleading-denial-friendly-headlines.html

  7. WAG says:

    Seems like this is the silver bullet which proves there’s no climate conspiracy. Scientists made a mistake. Other scientists spotted and pointed out the mistake. The original scientists accepted their errors and retracted the paper. No trying to cover up the mistake. No bruised egos or defensive, politician-style squirming. No intentional manipulation of data. Just an honest mistake, and an honest response. Sorry deniers, science still works.

  8. fj2 says:

    re: Nature sea level rise shocker: Coral fossils suggest “catastrophic increase of more than 5 centimetres per year over a 50-year stretch is possible.” Lead author warns, “This could happen again.” [29]

    So, yes the prior NPR post with Joyce was wrong. We should be measuring climate change in years not decades.

    Most people, and it seems even scientists do not have a clear picture of the scale we are talking about.

    They also do not have an idea of the scale of the solutions. Solutions have to be big. Real big. eCars don’t come close.

  9. Charles says:

    I’m with Scott Mandia. I don’t know whether to laugh or cry. The appalling ignorance is becoming hard to imagine … but the fact that so many are willing to swallow this codswallop is frightening.

  10. Andy says:

    Part of the blame goes to Siddal. His answer that the correct number could be lower or could be higher was pretty bogus given the nature of his main error.

  11. WAG says:

    Figured I might as well turn my original comment into a blog post on why this retraction proves there’s no conspiracy:

    http://akwag.blogspot.com/2010/02/silver-bullet-proving-theres-no-climate.html

  12. Mark S. says:

    Yesterday, the doc said I had 6 months to live. Today, he said there was a mistake and that my life expectancy is actually less than 3 months….what a relief!

  13. dhogaza says:

    “You got to be kidding me. Let me see if I have this right. The anti-science echo chamber is at full decibel because sea level rises are predicted to be much HIGHER than previously thought.”

    Yes, you’re exactly right. This kind of own-goal celebrating is actually common in the anti-science echo chamger.

    It would be laughably sad if it weren’t for the fact that there are 40+ senate votes that will embrace it as a reason to oppose CO2 emission controls.

  14. dhogaza says:

    Betsy Newmark allowed my post, explaining how she had it backwards.

    I’ll check a couple of the others (some had weird registration requirements I didn’t want to deal with)

  15. David Gould says:

    Absolutely amazing stuff. Well done for fighting this campaign of counterknowledge.

  16. jon says:

    if it keeps on raining, levy’s going to break, if the levy breaks, people you gotta move.

    how high’s the water papa? it’s 10 foot high and rising.

    According to some people, like Richard Alley in his ‘Two-Mile Time Machine’ there is enough ice on land to raise sea level 200 more feet and that the extremes are about a 600 foot difference, from glacial to interglacial periods.

  17. paulm says:

    I think the Guardian may have done this on purpose.

    All the kuffufle about it will make more headlines and then the real reason becomes clear, more of the public then realize that were up the creek.

  18. Steve Bloom says:

    Re #7: Oh, there very much are some bruised egos, although the retracting scientists behaved gracefully.

  19. prokaryote says:

    a sudden, catastrophic increase of more than 5 centimetres per year over a 50-year stretch is possible. On page 881, they describe their discovery that a sea-level jump of 2–3 metres already happened about 121,000 years ago.

    his earlier ice-sheet collapse happened during an interglacial, when it was warm and there wasn’t a lot of ice around — just as it is on Earth today. We’re assuming rapid ice loss from an ice sheet produced the jump in sea level, because it’s the only known process that could generate such a rapid increase. This could happen again.

    ____
    On page 881 …

    Given that sea level rise is not a global constant – means there are places with more and less sea level rise. Now i wonder about the geo-oceanic situation at the yucatan back than.

    Next IPCC 2014, that should be evaluated asap and not only because of the current critic – because of such urgent and importend updates.

  20. JimR says:

    “However, we overlooked that the simulations of the twentieth and twenty-first centuries are sensitive to this time step, which led to an overestimation of the sea-level response to warming in the simulations for these centuries.”

    The retraction makes it sound like this study had overestimated sea level rise, not underestimated it.

    [JR: Nah. Read the original RealClimate critique by Rahmstorf and Martin Vermeer, which turned out to be right.]

  21. Esop says:

    Crikey. I was just waiting for this one to blow.
    The denialist friendly Norwegian media is salivating over the news as well. The headlines read new climate scandal, climate scientists once again calculated wrong, and so on.
    Barely mentions the fact that the study was retracted due to an underestimation of the rise, but most people won’t bother to read to the very last paragraph of the article.

    Positively ridiculous.

  22. mike roddy says:

    Thanks for this one, and it only confirms what I’ve been reading the last few years.

    Joe, I congratulate you for being able to keep from going nuts over the way the deniers play games with reality. There was a group on Dot Earth who fought the deniers there for about two years, and most of us became overwhelmed by their stridency and inattention to facts. We would disprove and humiliate them, and they would not only concede nothing, 10 new denier troops would show up on the blog. I think that some of us (we had a separate newsgroup) are now on tranquilizers from arguments with a bunch of Rick Morano clones. It gets really weird after a while, and the moving goalposts talked about here rang a bell.

    We need more people like you, who just keep swatting them away. Before long there will be so much obvious confirmation that people will remember what you have accomplished here. Let’s hope you can reach enough of the public before it’s too late.

  23. TB says:

    Sorry – I think I’ve misunderstood you. You link to the Nature retraction in which it states the first mistake:

    “we overlooked that the simulations of the twentieth and twenty-first centuries are sensitive to this time step, which led to an overestimation of the sea-level response to warming in the simulations for these centuries”

    …and the second mistake:

    “we no longer have confidence in our projections for the twentieth and twenty-first centuries…pertaining to sea-level rise after 1900.”

    So the first mistake shows that they overestimated the sea-level rise, and the second mistake doesn’t say whether they over- or under-estimated sea-level rise.

    Why, therefore, do you conclude that this retraction is because the paper underestimated the sea level rise?? I also don’t understand why the Wonk Room claims the Author was “accepting corrections from researchers who had made the higher estimates” when there’s no mention of this in the retraction on Nature’s website.

    Very confusing.

  24. David Gould says:

    TB,

    Vermeer and Rahmstorf are specifically thanked. These are people who have made higher estimates, although there is nothing in the journal to tell anyone that.

  25. Martin Vermeer says:

    Retraction is good for the soul. So, Joe [D’Aleo], Anthony, what about it?

  26. Here is an interesting site that visually shows how sea level rise will influence major US coastal cities:

    http://www.architecture2030.org/current_situation/cutting_edge.html

  27. Apropos Foggy Bottom becoming Soggy Bottom, here is my illustration from GLOBAL FEVER showing a 6m (20ft) sea level rise lapping the back steps of the Capitol and almost reaching the State Department (upper left).
    http://williamcalvin.com/bk14/img/DC%20photo%20+6m.jpg

  28. Lewis says:

    Craig says:
    February 22, 2010 at 9:58 pm

    You got to be kidding me. Let me see if I have this right. The anti-science echo chamber is at full decibel because sea level rises are predicted to be much HIGHER than previously thought.

    They heard nothing but, “A climate scientist said he was wrong.” And as they want to believe that ALL climate science is wrong it would be more surprising if they weren’t cheering.

  29. TB says:

    Thanks, David Gould. Agree with JimR (#20) that the retraction suggests the study had overestimated sea level rise, not underestimated it. Can they retract the retraction and reissue it?

  30. Michael Y says:

    The retraction gives no indication of whether the top-end projections are no longer valid, or the bottom-end projections. I don’t know enough about the science to be able to confidently interpret the retraction one way or the other. If Mark Siddall really does mean to say that he might have underestimated the top-end projections, it would be great if he could say so on his site (as well as to the main media outlets). If he is unwilling to state his position in such a way, then are we (at climateprogress) in “spin” mode as much as the deniers?

    I sometimes feel like we have become nearly as shrill as the other side. :(

    Please keep up the good work. I visit the site daily to stay up to date.

    Best,

    Michael

  31. It is worth remarking on the famous story of the great Viking ruler King Kanut – who commanded the tides not to rise:

    “…he commanded that his chair should be set on the shore, when the tide began to rise. And then he spoke to the rising sea saying “You are part of my dominion, and the ground that I am seated upon is mine, nor has anyone disobeyed my orders with impunity. Therefore, I order you not to rise onto my land, nor to wet the clothes or body of your Lord”. But the sea carried on rising as usual without any reverence for his person, and soaked his feet and legs. Then he moving away said: “All the inhabitants of the world should know that the power of kings is vain and trivial, and that none is worthy the name of king but He whose command the heaven, earth and sea obey by eternal laws”. Therefore King Cnut never afterwards placed the crown on his head…”

    King Kanut should be the patron saint of global warming politicians. His fundamental PR lesson was just to say that it is foolish for any ruler, or politician to fight reality.

  32. Rockfish says:

    I’m with Wit’s End (#2)
    The more we keep enabling arguments about the science, the longer the status quo holds. There is a lot of profit for a lot of people tied up in the production of CO2 on this planet. They will argue about science, then about effects, then about solutions, etc etc, as long as possible.
    We have now spent FOUR MONTHS debating the minutia of peer review protocols and inter-scientist email etiquette in the mainstream media, while Rome burns.

  33. David Smith says:

    I’m sorry, but denier is too nice a word. I think we should call the active bloggers, politicians, business leaders,… on the denier side what they are; THE CHAMPIONS OF THE BRAIN DEAD.

  34. dhogaza says:

    Mike Roddy:

    There was a group on Dot Earth who fought the deniers there for about two years, and most of us became overwhelmed by their stridency and inattention to facts. We would disprove and humiliate them, and they would not only concede nothing, 10 new denier troops would show up on the blog. I think that some of us (we had a separate newsgroup) are now on tranquilizers from arguments with a bunch of Rick Morano clones.

    Well, about a week ago I decided to jump in on a couple of threads guest-posted by Dr. Lacis, one of Hansen’s co-workers at NASA. He was asked to, in essence, provide a concise primer on the physical science of CO2-forced warming.

    After which he was attacked in the comments as being a liar, etc etc.

    So, after a few posts trying to explain some fairly basic stuff like why water vapor concentration is a feedback of temperature, the following began to happen:

    1. Someone google’d my handle and then began using my real name as a handle. Posting, masquerading as me.

    2. Someone else began posting “proof” that I’m a member of Greenpeace (in actuality, what they uncovered was the fact that for three months in 2002, I contracted to do some software development for them). In this, they revealed the names of a few of my past colleagues in and out of the organization.

    In other words, harassment. And the moderators at dot earth are allowing it.

    Posting while masquerading under my real name is probably the worst, I’m amazed they allow it.

  35. Barry says:

    It isn’t surprising the denier cabal is spouting confusion and disinformation…that is their entire reason for existence.

    What is currently a problem is that the more mainstream media are playing a “sell the controversy” ratings game with it all.

    But take heart. The media eat their own. And it won’t be long until the “new” controversy that will sell ads is that “denier arguments shown to be shams to delay action. Climate packed with record heat energy causing the wild weather extremes, long predicted by climate scientists, to become ever more painful and costly.”

    At some point the hot news frenzy will be who is to blame for the disastrous delay in acting during the 1990’s and 2000’s. The questions buzzing on everyones lips will be what the verdicts will be. A 24-hour media cycle of perp walks, finger pointing and gavel pounding.

    Of course that would only happen if the climate responds as the vast majority of climate scientist say is 95% likely.

  36. dhogaza says:

    Regarding #35, the dot earth moderators have cleaned up the thread …

  37. Mark S says:

    WRT “overestimating the response”, I believe that refers to one parameter of their model, NOT to predicted future cumulative SLR.

    From RealCLimate’s critique:
    “(4) We did not yet receive the code at the time of writing, but based on correspondence with the authors conclude that for their values in Fig. 3 and table 1, Siddall et al. integrated sea level with 100-year time steps with a highly inaccurate numerical method, thus greatly overestimating the a-term.”

    Basically, they used an inaccurate integration method that effectively overestimates a parameter in their model, which allowed it to, more or less, reproduce the OBSERVED 20th century SLR. Using an accurate numerical method with their model UNDERestimates the OBSERVED 20th century SLR, indicating that their model is wrong and biased toward lower projections.

  38. mike roddy says:

    dhogaza, #35:

    I’m not surprised. There are some real scary ones over at Dot Earth, and there was an obvious orchestrated effort to take over the blog. They tried to dig up stuff on me, too, though it was harmless enough that I could laugh at it. And they call Joe Romm a “Climate McCarthyite”!

    If you would like help with Revkin, email me at mike.greenframe@gmail.com and I’ll forward it to his email address. This crap really has to stop.

  39. dhogaza says:

    If you would like help with Revkin, email me at mike.greenframe@gmail.com and I’ll forward it to his email address. This crap really has to stop.

    I think you might’ve missed my post #37 – they cleaned it up. To his credit, Revkin e-mailed me personally to ask for help finding the posts, and saying that the posts should not have made it through. It turned out that some other moderator had edited the posts using my real name as a handle and replaced that with the real name of the person posting as me, before I had made my last complaint (I’d complained earlier, and apparently after a day or so some moderator took action).

    They also deleted the post containing information about my relationship with a particular client.

    For those of you who made it this far, Revkin blew up whatever good will came from his cleaning up those posts by sliming the IPCC selection process for not putting Roger Pielke Jr on a new IPCC panel.

    Unbelievable.