Is Recent Greenland Ice Sheet Melting ‘Unprecedented’? Absolutely. Is It ‘Worrisome’? You Bet It Is.

Color graph of Arctic temperatures over the last 2,000 years

“Greenhouse gas emissions are overwhelming the [Arctic] system,” explained the coauthor of a 2009 Science article, “Recent Warming Reverses Long-Term Arctic Cooling.” The blue line is the estimate of Arctic temperatures over the last 2,000 years, based on proxy records. The green line is the long-term cooling trend. The red line is the observed warming in recent decades.

Another day, another bad New York Times headline:

‘Unprecedented’ Greenland Surface Melt – Every 150 Years?

The New York Times then launched into a critique of:

  1. NASA — for what they asserted was an “inaccurate headline” in its press release, “Satellites See Unprecedented Greenland Ice Sheet Surface Melt”;
  2. Most of the media coverage — for supposedly “hyperventilating” by accepting NASA’s use of the word “unprecedented”;
  3. Me — for using James Hansen’s term “reticent” for one of the NASA scientists who said, “if we continue to observe melting events like this in upcoming years, it will be worrisome.”

I interviewed one of the country’s top climatologists, Michael Mann, by phone, and another, Gavin Schmidt, by email. The bottom line is:

  1. People who live in greenhouses definitely should not throw stones
  2. Ditto.
  3. Not. Mann explained to me that “it’s absolutely worrisome” what’s happening in Greenland already.

Before I elaborate on all three, let me make a point about headlines, which I discuss at length in my forthcoming book “Language Intelligence.”

Headlines are important because research shows that most newspaper readers don’t get much beyond them. And NY Times headlines sweep across the internet through twitter, facebook, news aggregators and search engines.  Probably 10 to 50 times as many people see the headlines as read any substantial portion of the story.

I would define a flawed headline as one that, standing alone, is inaccurate or misleading or, as in this case, both. Indeed, this headline is so bad I’d urge the NY Times to change it. I write virtually all of the headlines on Climate Progress, and since I’ve had several thousand posts, I’ve had to change a few headlines over the years.

There’s nothing wrong with fixing a headline — most major news outlets do it on a regular basis. The only thing that would be wrong would be to leave a wrong headline unchanged.

Let’s run through why the NASA headline is fine and why the NY Times headline is not.

The NY Times asserts that “the space agency badly blew it earlier this week with this headline,” claiming:

Unprecedented means “never done or known before.” Yet the news release beneath the headline directly undercuts that description of this melting event, saying that it is rare — the last wide surface melt was in 1889, recorded in separate ice cores at the Greenland ice-sheet summit and in the northwestern part of the vast frozen expanse — and has happened roughly every 150 years over a long stretch of centuries, as recorded deeper in the ice. (Here’s a figure from a 1994 Science paper pointing to a series of such melt layers, reflecting summer warmth. Please see the postscript below for the key reference, provided by Lora Koenig of NASA.)

And yet Dr. Jason Box, a leading Greenland expert with “19 expeditions to Greenland since 1994, more than 1 year camping on the inland ice,” used the following headline on his blog,, “Greenland ice sheet record surface melting underway.” Hard for something to be a record if it isn’t unprecedented.

The most thorough response comes from NASA’s own Gavin Schmidt in a comment posted on the NY Times story (one he confirmed with me):

The NASA results are clearly unprecedented in the satellite record (and this is obviously what was being referred to), and come at the tail end of a strong increasing trend in summer surface melt area (as seen in data from the Steffen and Tedesco groups).

However, we know Greenland was warmer than today at many intervals in the past – the Early Holocene (from isotopes and borehole temperatures), the last interglacial, the Pliocene etc. so there is no claim that this is something that has never happened in the history of the planet.

Furthermore, the ‘every 150 years’ quote is very strange. The data on Summit melt layers – (discussed in the paper you reference ) and more easily visible here: – indicates that the [1889] event was actually the only event in the last ~700 years, and there have only been 6 in the last 2000 years (4 of which were associated with the Medieval Climate Anomaly btw 750 and 1200AD). Hardly a frequently recurring ‘cycle’!

The all-Holocene average that Koenig is referring to includes the warmer Early Holocene where orbital variability was driving warmer northern high latitude summers — and which is not relevant to the expected frequency in today’s climate.

The point is that, as the top graph shows, the Arctic was in a long-term cooling trend until human emissions reversed that trend (and yes, Arctic warming isn’t precisely the same as Greenland warming). Multiple, independent studies make clear that “recent global warming is unprecedented in magnitude and speed and cause.”

The NYT is simply wrong when it says “the space agency badly blew it earlier this week with [its] headline.”

And that means the media coverage wasn’t flawed, either.

I discussed the surface melt with Dr. Mann. Here is what he told me:

Ablation is occurring at an unprecedented scale as far as modern observations are concerned. To try to make a statement about how unusual this event in the longer term context, we are forced to turn to more tenuous evidence from ice cores. And that only gives us spotty evidence,  information from a small number of locations,  and it’s very difficult to determine from that sort of information alone, whether there is in fact a precedent inrecent centuries for the remarkable spatial extent of the melt we are witnessing.

The NY Times cites as evidence in support of its assertion that the NASA headline was incorrect, this part of the full release:

“Ice cores from Summit show that melting events of this type occur about once every 150 years on average. With the last one happening in 1889, this event is right on time,” says Lora Koenig, a Goddard glaciologist and a member of the research team analyzing the satellite data. “But if we continue to observe melting events like this in upcoming years, it will be worrisome.”

The NY Times then launches into a critique of my post that is not sustained by the facts:

But subtlety and reality don’t play well in some circles. Koenig’s careful description of the science and the uncertainty about what the future holds prompted a public spanking from the Center for American Progress climate blogger Joe Romm, who charged her with “scientific reticence” — alluding to NASA scientist James Hansen’s paper criticizing sea-level researchers for being overly cautious in 2007 conclusions about the possible rate of sea rise in this century.

It is hard for me to see how what I wrote qualifies as a metaphorical act of physical violence. In my post — ABC News On Stunning Greenland Ice Melt: ‘Scientists Say They’ve Never Seen Anything Like This Before’ — I quote Koenig’s line and wrote:

That statement is a classic example of what James Hansen called “scientific reticence.”

The scientific literature and recent observations — along with our ongoing lack of climate action — have long passed the worrisome stage (see the post last month “Greenland Ice Sheet Melt Nearing Critical ‘Tipping Point’ ” …).

That is the full extent of my supposed flogging of the good doctor. Seriously, “reticent” is perhaps the mildest word one could possibly use, which is no doubt why Hansen used in the first place to describe some of his colleagues. Since the NYT likes definitions, “reticent” means “the quality or state of being reticent : reserve, restraint.” Ouch! Stop it! You’re hurting me!

I stand by statement, which clearly referred to our entirety of knowledge about what’s going on in Greenland. Mann told me when I asked him whether recent Greenland melt was ‘worrisome’:

It’s absolutely worrisome.  Some of the statements that scientists have made on this are a classic example of scientific reticence, understating to some extent what we know.

Finally, the NYT headline appears to echo Fred Singer’s lame denier treatise, Unstoppable Global Warming: Every 1,500 Years (see “Unstoppable disinformation every 15 minutes from Fred Singer“).

Hundreds of thousands of people will see nothing more than this one line: ” ‘Unprecedented’ Greenland Surface Melt – Every 150 Years?” Many will interpret that to mean the NY Times is mocking or downplaying what is happening in Greenland.

The semantic questions raised by the NY Times do not appear to be a productive use of their considerable resources. It appears that NASA’s headline was quite reasonable. It also appears that the New York Times‘ headline was quite unreasonable. They should fix that, especially since it is now becoming a bad habit:

This post has been updated.

46 Responses to Is Recent Greenland Ice Sheet Melting ‘Unprecedented’? Absolutely. Is It ‘Worrisome’? You Bet It Is.

  1. Your headline would have been better had used used “Surface Melt” rather than “Ice Melt.”

  2. Jack Burton says:

    I have noticed that the real science that confirms global warming and it’s causes is getting completely bogged down in trivial semantics. More and more attention is payed to how weather and climate are presented and what terms are used when reporting events and data.
    Getting all hung up on the use of one word, “unprecedented”, rather than focusing on the context of the Greenland melt and the longer term trends upon which this years melt is overlaid, is s useless exercise. Frustrating to see all the press go to a debate over a word rather than a focus on the rapid warming over Greenland and the rapid melting of parts of Greenland when the natural cycles favor cooling of Greenland as the graph so well point out.
    If I didn’t know better, I would believe all this semantics debate is just another climate change denier tactic. And believe me, these deniers are the masters of diversion. If your house was burning to the ground, would you stand around and debate whether the flames will cause the roof to collapse before they burn through the supporting joists of the ground floor? NO, you wouldn’t. Some debates are diversions from the essential points.

  3. Byron Smith says:

    Thanks for the summary and extra info. I had been confused about the extent of the evidence for widespread melts and this has helped to get a handle on it.

    BTW, typo: *treatist–> treatise

  4. Henry says:

    In the news biz this is known as “Jumping the Shark”!

  5. Joe Romm says:

    I still would’ve needed “ice” and it would be awkward. Headlines can’t explain everything, that just have to be fairly stand alone.

  6. jyyh says:

    I’d say because this event was seen as it happened, and ALL the previous ones were found out way afterwards, the use of unprecedented isn’t so farfetched. There was no one there in 1889, nor during the Medieval Warm Period (800-900 years ago) which was the previous occurrence before 2012 and 1889.

    At least we now see that Greenland Glacier Summit can melt, at these CO2 levels, for it is ice, and not some magical unmeltable H2O that the deniers would love to be present everywhere outside ablation areas of glaciers and ice sheets such as Greenland Ice Sheet (GIS), West Antarctic Ice Sheet (WAIS) and East Antarctic Ice Sheet (EAIS).

    If I recall correctly, there already was a similar sort of melting event on the Ronne Ice Shelf (This is the area of near sea level glacial ice partially floating in front of the WAIS if looking south in parts of the southern Ocean) some years back, that went mostly unnoticed in the media, but of course GIS is nearer to the media centers so it has been published.

    So, if this event happens again in the near future we can be certain the local Greenland temperatures of MWP levels have been reached. And if these events continue for several years in row, we can be sure Holocene optimum temperature levels have been surpassed in Greenland. And if these events continue for several years and do get longer in duration, so that the ablation area of GIS is the whole ice sheet, we can be sure that Greenland Ice Sheet melts.

    Sorry to be so long-winded, but I tried to be somewhat accurate with the words.

  7. Merrelyn Emery says:

    Nice hockey stick you have there!

    Seriously, it looks as if this rear guard media action will continue right up to the last gasp, ME

  8. Lewis Cleverdon says:

    Given the unprecedented extent of this melting right across Greenland,
    and given the local feedback with a layer of darker ice (not snow) now covering the island to allow more rapid deeper melting in future,
    and given that feedbacks from the loss of arctic ice overall are now interacting with other feedbacks as far as 1,500 kms into N American and Russian permafrost,
    and given that global cryosphere decline was reported back in 2010 (Geophysical Letters) as already imposing a warming equivalent to about 30% of annual anthropogenic CO2 outputs,
    I’d like to propose a wager with Dr Hansen (whose scientific record has my profound respect).

    I’d like to bet him that by 2025 he will regret allowing the political promotion of 350ppm as a safe ceiling for CO2 concentration under his scientific authority, and that by then he’ll accept that the rational safe objective is actually to recover sufficient carbon to restore the pre-industrial level of airborne CO2.

    The price of the wager I’d propose as being that the loser will spend at least one percent of their salary on the best bottle of wine it will buy, and share it with the winner (or, if one doesn’t drink wine, that the loser will give that sum to an NGO of the winner’s choice).

    The year 2025 is not chosen at random but specifically for the reason of CO2 concentration having passed 350ppm 38 years earlier during 1988, with that 38 year interval being roughly central within the widely accepted 35-yr to 40-yr length of timelag on warming from GHG outputs (due to ocean thermal inertia). Thus it is not until 2025 that we’ll experience even the direct effects of 350ppm of CO2.

    We can tell a certain amount of how much climate destabilization will advance by then from the Keeling curve of CO2ppm since 1959 (at Mauna Loa). Present warming and consequent destabilization may be ascribed to CO2ppm (plus proportionate minor GHGs) 38 years ago in 1975, which Keeling shows as 331.08ppm of CO2. Adopting the estimate of pre-industial CO2 at 280ppm, this implies that 51.08ppm of anthropogenic CO2 (plus the minors) has caused both the present warming (taken as 0.78C) and its related climate destabilization.

    The rise from 331.08ppm in 1975 to 350ppm in 1988 was of 18.92ppm, which was an increase of 37.04% in anthropogenic CO2. Thus on a pro rata basis the increase in warming we’d see by 2025 would be of 0.78C x 37.04% which is 0.289C, giving a total of 1.07C, with a corresponding rise in both extreme weather impacts and, critically, in greatly accelerated change in the status of the diverse interactive mega-feedbacks and in the timelagged warming they’d impose during the 2060s.

    Since these consequences of 350ppm of CO2 patently sound anything but ‘safe’, and since Dr Hansen is evidently a scientist of integrity and will readily admit an error, I’d be confident of winning the bet if he were game to take it on.



  9. Thank you for continuing to blow the whistle on what boils down to tragic combination of arrogance interwoven with incompetence in the vital area of climate science reporting at the New York Times.

  10. prokaryotes says:

    The amplifying feedback mechanism of polar ice melt is the so-called albedo-flip effect, where loss of reflection by melted ice is compounded by infrared absorption by open water, a process currently taking place in the Arctic Sea, as reported by Hansen et al.: “… amplifying feedbacks make ice sheet disintegration necessarily highly non-linear. In a non-linear problem, the most relevant number for projecting sea level rise is the doubling time for the rate of mass loss. Hansen (2007) suggested that a 10-year doubling time was plausible, pointing out that such a doubling time from a base of 1 mm per year ice sheet contribution to sea level in the decade 2005-2015 would lead to a cumulative 5 m sea level rise by 2095.”

    “Just the melting of all the floating ice in the arctic ocean, will add as much heat to the earth, as all the Co-2 we put in the atmosphere to date.” Prof. James Lovelock

    Estimating the Global Radiative Impact of the Sea-Ice-Albedo Feedback in the Arctic a more realistic ice-free-summer scenario (no ice for one month, decreased ice at all other times of the year) results in a forcing of about 0.3 W m−2, similar to present-day anthropogenic forcing caused by halocarbons.

  11. María says:

    A new carpooling website with a new search engine designed for the city and with maximum privacy settings by default

  12. Spike says:

    Greenland on Borrowed Time – an article by a UK climate scientist in the Guardian

  13. Peter M says:

    The New York Times will be looking for ‘other factors’ besides greenhouses gases to explain a climate out of control even when the subway system becomes flooded and increasingly unusable.

    As the climate revs up and begins to rebel against the excessive amounts of C02 from 2 decades ago, the NYT will still be in tight with the denial folks. But for how much longer?

    As was said here, at this point 350ppm is likely too high- Hansen said this might be the case- 325ppm looks far more realistic.

    The climate is showing profound sensitivity to C02. I wonder what 395ppm will look like with reduced aerosols around 2032- when the actual amount of C02 is at 450ppm- will the ‘vaunted’ NYT is still debating AGW?

  14. BillD says:

    I was concerned by the NASA interview on PBS newshour on this, since the NASA scientist showed no concern and almost seemed to emphasize that similare melting had occured a century ago. The word “unprecedented” isn’t the best if the story includes a comment about an earlier event. On the other hand, “record, drastic” seem appropropriate. In the PBS case, it would have made a big difference if the scientist has said that the melting was a big concern, instead of just smiling and being chipper.

    It’s propbably also true that most people only read the title. Over at WUWT, they hardly seem to read the abstract of a scientific paper before interpreting and critisizing.

  15. Joan Savage says:

    The unprecedented event in 30 years of satellite observation is a near doubling of the surface areal extent of ice melt, having reached 97% of all ice surface as of early July 2012.

    This may indicate that the mass balance of interior Greenland ice is becoming more vulnerable. In recent decades, the interior ice appeared to have its surface melt losses recouped by heavier winter snowfalls.

  16. Lollipop says:

    I have to say I find this whole episode very demoralizing. It seems increasingly obvious, to me here in central Indiana as I watch our crops wither and out trees turn brown, that nothing, and I do mean nothing, will be convincing enough to the bulk of the population. It was an insane 106 here this week, according to my thermometer and the ones on our banks. If that isn’t enough to convince people we need to change I don’t what is. Do they believe in climate change, yes many of them do. Are they ready to fight the good fight to create a carbon neutral economy? No. Even the farmers around here, including my own CSA farmer, aren’t willing to step up and fight. The change we need to create is too big, too all encompassing, too blocked by big oil. I honestly don’t see how we get from here to there. I’m writing a book about how my profession can adapt to global warming (under contract with my professional society, due to them in January) and I’m really struggling to put the positive spin they want on the whole situation. If people whose livelihood is directly under threat can’t see through the BS to start fighting, how can I expect anyone else to begin making the big changes needed? Sigh.

  17. The attitudes expressed by elites matter quite a bit, based on recent climate psychology research. Hard for individuals to see the hope or benefit of acting for a commons, if leaders don’t also express support.

    That’s where bad mainstream media – and especially, failures of elite media like the NYT and NPR – not to mention the lack of public leadership from most of the national administration – are daunting.

    Perhaps other elites can help bridge the gap, temporarily to start significant change, through a grand coalition of the willing.

  18. Professional societies, as a sort of second-tier elite, can probably contribute significantly to a “grand coalition of the willing” strategy, as presented recently in Nature Climate Change and outlined here…

    Roadmap to turn the tide on climate change

  19. Lollipop says:

    I hope so. I’m a librarian, so we do play an important role as educators and I think we are in a good position to be influential in the IT realm since we represent a huge consumer base, but I’m having one of those days where it all seem rather hopeless. My redbud tree seems to have died in the drought, so I might be projecting a bit. I loved that tree and I’m not convinced it is coming back next year.

  20. Lewis Cleverdon says:

    Peter – can you post any links to your source for a 20yr ocean-thermal-inertia timelag on GHGs’ warming taking effect?

    I’d be very interested to read such since on this side of the pond a lag of 35 to 40 years has been widely accepted for decades. The difference in terms of just what warming and related climate destabilization is already “in the pipeline’ is plainly pivotal to our prospects.

    Regarding a stabilization target of 325ppm, you might be interested to search for the paper (in Nature, around 2000) by Dr Foreman of Aberystwyth University on the correlation between elevated CO2 and peat bogs’ decay. For almost 40 years scientists had puzzled over the steady worldwide rise in dissolved organic carbon [DOC] in the outflow streams from peat bogs, which then outgasses as CO2 quite rapidly. The DOC increase’s correlation with rising airborne CO2 was very strong but the mechanism was obscure. Foreman identified how elevated CO2 allowed one peat microbe to boom its population, thereby allowing another which ate it to boom, and how the latter does so by using an enzyme that happens to decompose peat.

    To put this feedback in context, the phenomenon of rising DOC in outflows was first observed worldwide in ’62, when CO2 was at 318.45ppm, since when it had risen at a rather steady 6%/yr. Foreman reported (around 2000) that the trend might be accelerating, but that if it held steady then by 2064 the annual output of CO2 from this source would equal the entire anthropogenic output for the year of publication.

    From this perspective the prospect of stabilizing CO2 at 325ppm seems rather unlikely, particularly given the rate at which fresh examples of potent amplifyers within feedbacks are being discovered, (such as the taurus effect within ex-permafrost melt pools) thus indicating that current knowledge is still rudimentary. Moreover the interactions between feedbacks plainly hold further surprises – such as the arctic albedo loss disrupting the Jet Stream which in turn generates droughts threatening the combustion (gassification) of the 43 million acres of US forest now dead or dying due to the bark beetle explosion.

    In acknowledging how limited is current knowledge of the diversity and interactions of the feedbacks, it is hard to see a cogent justification for attempting a stabilization of CO2 at least 45ppm above the pre-industrial level.



  21. Mike Roddy says:

    The Times has been schizoid on this subject for a long time. They sort of want to tell the truth, but feel the hot breath of the fossil fuel advertisers every day, and the banks that profit from them.

    Advertising from oil and gas could make the difference for their profitability or even survival.

    Since this is the case, it’s better to let the paper die, and be replaced by an organizaton staffed by reporters who are not afraid to report what’s actually going on.

  22. SecularAnimist says:

    Joe wrote: “Many will interpret that to mean the NY Times is mocking or downplaying what is happening in Greenland.”

    And “many” would be correct in that interpretation.

    The NY Times has consistently and systematically mocked and downplayed ALL of the ongoing impacts of anthropogenic global warming.

  23. Tom L says:

    New York Times: Don’t worry, go shopping, and don’t let anything, or anyone, shake your ‘consumer’ confidence. Your duty, as useful idiots, is to obey your great grey momma and support corporate profitability as long as possible with your easily manipulated ignorance, Idiots.

  24. john atcheson says:

    The Times reporting was certainly egregious. But we have to lay some of the blame on Lara Koenig. I heard her on NPR and she repeated the every 150 years claim. She was quite bold in asserting this was a confirmed and expected cycle, but similarly reticent when talking about the implications for the future.

  25. M Tucker says:


    Should be tattooed in reverse on the forehead of every Times editor and environmental blogger so that they will be reminded each morning when they look in the mirror.

    It seems to me that unprecedented melting has become so common that many of those whose job it is to inform the public have become resistant to describing new melting events as unprecedented. Manhattan sized ice burgs no longer really get much attention. Arctic melting opening up the Northwest Passage in the summer no longer makes the news. Coastal glaciers speeding up their march to the sea is mostly forgotten by the writers of stories like this. The mountain glaciers are going. The Antarctic is melting too. The Larsen A and Larsen B ice shelves are gone except for a small remnant of B in the Scare inlet. The experts expect it to go very soon. The larger Larsen C ice shelf is showing the all the signs of melting. Other shelves along the coast are melting from below due to a warmer ocean. The expected sea level rise due to the melting of the glaciers buttressed by these shelves is not being taken into account. IT IS ALL UNPRECEDENTED!

  26. climatehawk1 says:

    Yes, and Joe’s headlines are already too long for Twitter.

  27. Peter Malsin says:

    In my experience, Justin Gillis’s pieces comprise good climate-change journalism while (I agree with others here) Andrew Revkin comes across as a closet toady. But at least he’s addressing issues, which is pretty rare in mainstream journalism.

  28. David Lewis says:

    Hansen is on record repeatedly saying 350 isn’t some limit he’s certified as safe.

    The way he talks about it is he says 450 ppm is a “recipe for disaster” as it seems to him too likely to produce an ice free planet. He says McKibben was bugging him for a number.

    He came up with something less than what is in the atmosphere now and answers those who say why should any value higher than the preindustrial be suggested as reasonable by saying after we stabilize at 350 we will be in a better position to determine what is safe in the longer term. Unspoken I’d say is if you are talking about a goal that everyone is telling you will be impossible to achieve and that you are insane to put it out there, why go further to 280 ppm or even less?

    I started advocating returning the atmosphere to the preindustrial as early as 1988. You can tell where I got with that, as you’ve never heard of me.

    Hansen gives talks on the planet’s energy imbalance and points out that it would take a reduction from today’s CO2 level around that 350 mark to reduce the imbalance to zero, but he knows there are other factors to worry about that aren’t in that rough calculation. What is the precise masking effect of all the anthropogenic aerosols (which he says is significant, and he says we are completely ignorant about what the actual value is), which will be largely gone if civilization was ever to get the atmosphere back to 350 ppm presumably, what about the other GHGs, what about the positive feedbacks already initiated by the slight warming that has already happened.

    He knows all this and has good ideas about what the magnitude of each is yet he still talks about 350 ppm because he thinks it is meaningful. It has a meaning. CO2 deserves to be singled out, he says, because once civilization has emitted it, “you can’t get it back”, all the CO2 removing plans notwithstanding, due to the astronomical cost of removing a significant amount.

    People critical of 350 note that it hardly matters to say 350 or 450 because at this point the initial policy would be very similar, and you’ve got very widespread agreement on 450 by now whereas 350 is a bit more controversial. To achieve either goal we’d have to reduce CO2 emissions globally at a far faster rate than any single country has achieved, eg even when the heavy industry of the former Soviet Union collapsed after the Soviet Union was dissolved and living standards fell drastically. These critics say its better to point out how many more tonnes of CO2 could be added to the atmosphere if “x” percentage chance of staying below “y” temperature increase is to be achieved.

    Hansen has said one reason he talks about 350 ppm is because once you realize there’s more than that in the atmosphere already “you know which way you have to go”. I would note that critics of him, such as Anderson of Tyndall, think what they say would get through to people exactly what Hansen is trying to get through to people, i.e. drastic action is now required because what is happening now is a commitment to higher and higher levels of damage is being baked in. All we can do is attempt to keep the planetary system from heating up out of control to beyond where civilization could adapt.

    It seems to me various people have their ideas about what to try to successfully get civilization to act, and since nothing is working, there is a temptation for people to criticize each other on minor points.

    Hansen isn’t going to be regretting anything, except he will feel that he failed to convince enough people to stop what he saw so clearly from happening.

    He’s doing everything he can see it would make sense to do, and he’s been more effective than almost anyone else on the planet.

  29. David Lewis says:

    Its past time to stop granting Lovelock the slightest bit of credibility as knowing anything about climate science. He decided several years ago he was mistaken about how serious climate change is. He has been telling people that the views of climate science denier Garth Paltridge should be taken seriously. Paltridge (author of The Climate Caper) preposterously asserts that the IPCC scientists are the worst thing that has happened to the enterprise of science itself in the last several hundred years because they have trumped up the climate issue without evidence into the “ultimate example of the politically correct”. Lovelock wrote his friend Stewart Brand to tell him he can’t understand why his climate scientist friends now “shun” him.

  30. Artful Dodger says:

    Merrelyn, Germany arrested and charged a NAZI war criminal last week… yes, this type of rhetorical rear action will continue well after the worst of climate change has set in.

    “…appear to be a productive use of their considerable resources”

    Indeed, how much ad revenue does the grey lady receive from the black hats of big oil?

  31. David Lewis says:

    In my perhaps flawed understanding, Hansen has been saying he believes all current climate models mix too much heat into the ocean, hence he thinks all models produce climate response too slowly.

    The evidence he has is the Argo float data which he says is sort of looking solid, more solid than any previous attempt to measure what’s happening in the oceans. He admits there is still a possibility they might find a systemic flaw in the network. But he’s publishing his ideas based on if there isn’t some systematic flaw with the Argo floats.

    His assessment of what it means is the net force acting to heat the entire system is less than what models calculate. He gets to this conclusion by imagining a model that has less heat going into the ocean, and shows that given that, given that GHGs will have the same properties, a model could produce a good fit to existing global average surface temp data if aerosols were reflecting more heat out to space than most assume now.

    His existing GISS model, he says, is clearly producing an inaccurate result as to where the thermocline is, and he says he has some data on what dissolved CFCs are doing in the southern ocean that confirm his idea that ocean mixing of heat is actually proceeding slower than most assume.

    He shows what happens to models if you alter basic things like this. You can alter several values in plausible ways and get very similar fits to existing data. He’s looking for more proof that he is right.

    “Are we getting the right answer” [the model results that fit observations] “for the right reason?” Hansen himself explaining these ideas on Youtube

  32. Chris Winter says:

    Paltridge is the co-author (with C.M.R. Platt) of Radiative Processes in Meteorology and Climatology (Elsevier, 1976.) So he has some climatology chops. But at first glance I’d say this is a case of “gone emeritus” — if only because he let TVMOB write the foreword to The Climate Caper (Taylor Trade Publishing, 2010.)

  33. Chris Winter says:

    I don’t know Dr. Hansen’s salary (nor do I need to), but I’ll hazard a guess that the payout from this wager would be in the neighborhood of 10^2 sawbucks ($1,000). You could purchase one heck of a bottle of wine with $1,000. These French burgundies are examples:

    Emmanuel Rouget Cros Parantoux Vosne-Romanee Premier Cru Cote de Nuit burgundy: $1,079

    Domaine Leroy Clos de Vougeot Grand Cru, Cote de Nuit burgundy, France $ 951

    The list: (based on average mid-2012 prices)

    But my suggestion is: Go for a case of wine at about the same total price. Perhaps this 2006 Alain Burguet Vosne Romanee ‘rouge Du Dessus’, available from Beltramo’s in Menlo Park, CA for $115 the bottle. Or, if you prefer American varietals, the 2005 Barbour – Cabernet Sauvignon Napa Valley sells for the same price. (Yes, I’m partial to reds.)

    Of course, by 2025 there may not be any French burgundy or Napa Valley cabernet. Perhaps a good Manitoba would fill the bill.

  34. Peter M says:

    Lewis C- I believe that David Lewis heard the same extrapolation from Hansen As I did.

    35-40 years seems like an awfully long time. C02 levels 45ppm above the PI levels of 280- are far better then over 100ppm as is today.

    Frankly however I do not think we will ever see 350ppm, let alone 325ppm again. Unless the entire economy collapses and we revert back to a farming pre industrial society (which could happen) if we are foolish enough to allow temperatures to rise 4 degrees C above the PI level.

    Falling back to 350ppm if we cease emissions after peaking at 650-800ppm would take several thousands of years.

  35. Solar Jim says:

    From another CP post:
    “Then we’ll see the melt area expanding abruptly and potentially covering the entire ice sheet in summer for the first time in observations.”
    Box said the shift may take another decade or so, provided that current trends continue. “We’re right on the threshold.”

    Change “another decade” to “another month.”

    As I have said, the planet’s response appears to be EXPONENTIAL, not linear. This means that all nation-state policies are currently irrelevant, including all IPCC scenarios.

  36. David Lewis says:

    Paltridge’s The Climate Caper is indeed as bad as you would think anything that had a Foreword by The Viscount Monckton of Brenchley, a.k.a. Lord Monckton would be.

    Lovelock convinced his old friend Stewart Brand (of Whole Earth Catalog fame) that Paltridge is a “sensible skeptic”. Brand didn’t notice his old friend Lovelock had lost it, never had it, or had gone senile. Brand accepted the evaluation of Paltridge Lovelock was shovelling out, i.e. Paltridge knows and the IPCC and almost the entire climate science community worldwide don’t know. He then wrote about how there are ideological “Calamatists” who are alarmed about climate and scientific “Warners” are also alarmed but there is a difference – only “Warners” respond to contradictory evidence. Naturally, Brand thinks Lovelock is one of the “Warners”.

    Brand explains this in his online <a href="Afterword.

    Lovelock cited the “Missing Energy” paper Trenberth published in Science as his prime piece of current research that caused him to reevaluate his position. Trenberth, who has heard Lovelock is uttering gibberish these days, says this: “The fact is he knows little or nothing about climate change.”

  37. Lewis Cleverdon says:

    David – I’m sorry my post seems to appear to you to be critical of Dr Hansen – I’d hoped to avoid this by making explicit my respect for his work and his character.

    My intention was not to criticize but to present an alternative view of the necessary strategy and to note that partial measures of ppm reduction invite disabling slippage in debate – as to what is the scope of ‘adaption’ that cuts the need for reductions – what is affordable – what is currently ‘realistic’, etc. My preference is for what is necessary for safety, given our limited knowledge of the burgeoning feedbacks.

    We differ I think on the feasibility of carbon recovery, possibly because as a student of traditional forestry techniques over several decades I recognize the potential for largely self-funding carbon recovery via the income streams from utilizing coppice forestry for charcoal. These include minor national fees for sequestration of nations’ historical carbon emissions, plus the sale value to farms of charged charcoal as a soil moisture regulator and fertility enhancer, plus the sale value of co-product energy carriers (particularly including methanol).

    Even using the huge scale of afforestation that the WWF/WRI study reported as feasible worldwide without diverting farmland – around 1.6GHa.s – this would be no quick fix of airborne carbon. With both a fairly stringent global emissions budget reaching near-zero by 2050, and with sufficient albedo-restoration to halt the further acceleration of the feedbacks and their rising CO2e outputs, restoring a pre-industrial level of airborne CO2 would take at least the rest of this century. Were either of those two related goals neglected the task would be impossible as far as I can see.

    Equally, without carbon recovery on a massive scale, even in combination emissions control and albedo restoration are insufficient in the long run, given the acidification threat to the oceans as the basis of the biosphere. And I take it you know full well the very long timeline for natural carbon recovery once a substantial CO2 level is imposed.

    My preference for making explicit the ‘full term’ ppm goal is not about some fundamentalism but precisely about the politics which leads Dr Hansen to have promoted 350ppm, with his proviso that future revision can be applied as needed. In this it seems we share some history – I too supported 280ppm in the late ’80s, though by the mid’90s I was working with GCI (mostly at UNFCCC COPs in Geneva) on tabling and promoting the Contraction & Convergence framework, alongside which we proposed 350ppm as the rational stabilization goal. (At the time, in the talks 550 was controversial and 450 was seen as radical).

    Over the years, with the obstruction of negotiations for nationalistic advantage and the rapid emergence and acceleration of the diverse feedbacks, it’s become more clear to me that the ‘full term’ ppm goal is both relevant and necessary to breaking the deadlock and advancing popular demand for specific commensurate action.

    A scan of the web will yield umpteen calls for politicians “to do more” and much ‘climate-porn’ of disastrous looking ecosphere developments, but very little indeed on just what are the end goals of action and why – (which ordinary people need to commit their time and morale to campaigning) – and even less as to just what exactly we require politicians to do. For instance, where’s the discussion of which framework for the allocation of national emissions rights within a global CO2e budget offers both the necessary simplicity for efficiency and sufficient equity for durability under the coming intense stresses ? Until politicians face rising demands for such specific proposals we are I think on a hiding to nothing.

    Setting 280ppm as the full term goal for carbon recovery is not only about giving campaigners a credible destination to fight for, it is also about advancing the recognition of carbon recovery as the sufficient complement to the necessary emissions control and albedo restoration. Moreover, it is of potentially critical significance in resolving a key obstruction of the negotiation of binding treaty commitments, namely the fraught issue of historical emissions. Until an affordable and benign means of incorporating those emissions is found, real progress looks stymied. I suggest that the largely self-funding approach to carbon recovery proposed above is the most promising means available. For nations to agree to verifiably recover those emissions over a chosen period would remove a key log from the logjam of the negotiations. And the full term goal, of restoring the ‘natural’ atmosphere with say 280ppm CO2, is of major relevance to potential popular demand for this outcome, in a manner which no interim goal can match. Perhaps this difference is best described by remarking that while 350ppm by, say, 2080 is a notable waypoint, it lacks the far stronger emotional appeal of the destination of 280ppm by 2100.

    After seeing your initial response I’m minded to amend the wording of the proposed wager – something on the lines of –
    “that by 2025 Dr Hansen will no longer wish to see 350ppm promoted as a safe level of airborne CO2”
    may seem a more appropriate form of words.



  38. Mulga Mumblebrain says:

    Of course it’s a denialist tactic. In The Guardian, the supposed ‘liberal voice’ of the UK Rightwing MSM, today there is a quite dumb piece on the Greenland melting by some hack whose previous claim to fame is judging the Turner art prize, infamous for its rubbish ‘winners’ (and insult to the memory of the immortal JMW). As the few sane commenters noted, the article was incoherent and contradictory, at one stage asserting that such melting occurs once every 150 years, so ‘is right on time’. Won’t the denialati love that. The article is one of a series The Guardian calls ‘Framing the Debate’, and we all know how The Guardian and the rest of the Western MSM ‘frame’ every debate to suit power.

  39. Mulga Mumblebrain says:

    Perhaps she’s advertising her wares as a new Curry. ‘Currying favour’, as it were.

  40. David Lewis says:

    I wasn’t thinking of you when I mentioned critics of 350 ppm as advanced by Hansen – I had Myles Allen, head of the Climate Dynamics group, U of Oxford, in mind. Here’s an audio of Allen making his critique of all those who advocate to civilization they should conceive of the problem they face as one of aiming for stability at some level of ppm. Allen was a Lead Author for AR4 on detection of change and attribution of causes, etc.

    For what it’s worth, the Hansen group’s Target Atmospheric CO2 paper used the phrase “at most 350 ppm”, and suggested this “may be achievable by phasing out coal use except where CO2 is captured and adopting agricultural and forestry practices that sequester carbon”. The stated concern was to avoid the “possibilty of seeding irreversible catastrophic effects”. They note in that paper that “there are no large-scale technologies for CO2 air capture now” saying his groups assessment of the literature suggests with “strong R&D support and industrial scale pilot projects sustained, over decades it may be possible to achieve costs ~$200/tC or perhaps less”. They cite David Keith on the $200 figure and Klaus Lackner on the “perhaps less” figure. Keith is the lead author for the AR5 geoengineering CO2 capture section or even geoengineering itself I believe. Lackner is the most optimistic CO2 capture guy on the planet. The Hansen group estimated if air capture gets to $100/tC it would cost $20 trillion per each 50 ppm removed.

    The Hansen group note that “deforestation contributed a net emission of 60+-30 ppm over the past few hundred years, of which ~20 ppm remains in the air today” and says “reforestation could absorb a substantial fraction of the 60+-30ppm net deforestation emission”. When addressing “sequestration in soil” the paper states it has “significant potential” to store carbon for “centuries to millenia”. The group offered what they call a “forest/soil drawdown scenario” in their Supplementary Material “that reaches 50 ppm by 2150” which in their minds could return “CO2 below 350 ppm late this century after about 100 years above that level”. They saw potential in “replacing slash and burn agriculture with slash and char and use of agricultural and forestry wastes for biochar production” indicating they saw “~8 ppm or more” per 1/2 century using this tactic. They cited Lehman, Bio-char sequestration in terrestrial ecosystems – a review.

    I don’t agree with your reasoning that there is some big difference between 280 and 350 as goals people could organize around. Both targets only address part of the problem in any case, i.e. anthropogenic emissions of other GHGs aren’t in them. And both targets assume that positive feedbacks already triggered aren’t going to prove to be irreversible as of now.

    I think getting people to see that there is a problem and getting them to agree that civilization needs to live within the limits the planet has, whatever they are, is the only wise course of action that can be adopted if our species is to have a possibility of a future living on Earth is about as fleshed out as the present state of knowledge allows anyone to say. Given that, a target concentration of less than what is in the atmosphere conveys a message that there isn’t any more leeway before action must be taken.

  41. Mike Roddy says:

    IPCC is already irrelevant. There is a five year gap between research and IPCC inclusion. Considering what we’ve seen just this year, this is a joke.

  42. Solar Jim says:

    Thanks for interesting comments from two people who share the name Lewis.

    Dr. Hansen’s recent estimate of planet energy imbalance is 0.58 W/m2. With about eight percent for ice melt, I estimate this is the equivalent of about five times the world electric generating capacity. The trend for radiative forcing is upward substantially.

  43. Solar Jim says:

    Time lag seems to relate to Dr. Hansen’s discussion of Climate Response Function. We do not appear to know what the value is, but models so far are showing something like 40% over a few decades, 60% temperature response after one century, with the rest over a couple thousand years. (If my interpretation is correct.)

  44. Solar Jim says:


  45. ultraverified says:

    Let’s cut to the chase:

    Revkin is a corporate tool who wants to maintain the status quo of continuing the use of fossil fuels. Revkin pretends to be an ‘environmentalist’, but read him carefully: I have for years. He’s always been a naysayer, embracing the cheapest of veneer of ‘alternative energy’, but supporting the interests of the conglomerates and centralized distribution of power over any substantive change needed to reform our energy policies.

    That people are finally realizing how much these traditional news outlets like NYT are, and people like Revkin serve as mouthpieces for huge conglomerates and multi-national corporations is a good thing.