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  1. Ah, you scientists and your….science. The fear the Guardian is stoking arises not from numbers, variability and noise. The fear is of this unknown. Your point is well-made that the unknown needs to be made into the known, but presently it’s still a bit ‘scary’. A single letter from Professor Visbeck means someone agrees with you, but the Guardian is for us lay people – and we have our fears. I have my fears.

    Is it a fact the for 10 days the current practically shut down? Then there’s something going on, which may or may not be a big deal.

    It is important not to be alarmist, but it is important to be alarmed.

    From the post:
    “the inferred deep western boundary current appeared to be very weak indeed. But then it came back.”

    From the Guardian article:
    “He added: “It only lasted 10 days. But suppose it lasted 30 or 60 days, when do you ring up the prime minister and say let’s start stockpiling fuel? How can we rule out a longer one next year?”

    Comment by Ed Arnold-Berkovits — 31 Oct 2006 @ 11:02 AM

  2. “Is it a fact the for 10 days the current practically shut down?”


    “…. explanations for the variability (deep eddies? waves?) are not yet available. Thus, no-one has any clue whether this is normal or unusual”

    “… the variations day by day varied by around 5 Sv (1 Sv is about 10 times the flow of the Amazon). The mean over the year for the MOC was 18 Sv ….

    Can you imagine a flow of water 180 times the Amazon river could have “almost stopped” and restarted without causing a ripple or splash?

    Take a large turbulent variable flow, 180 times the Amazon.

    Put a handful of little instruments out in it:

    Some of the instruments will be in waves, some will be in vortexes, some will be pointing up, down, sideways and backwards in a turbulent flow.

    On average — over time — you’ll get enough numbers to do the math and have what statisticians will consider a valid result saying it’s going thataway and that fast.


    Comment by Hank Roberts — 31 Oct 2006 @ 12:03 PM

  3. Let us state that at the presnt time there is little evidence in the available data for a slowdown in the atlantic current which contributes to Europes relatively mild winter climate. Maybe in years to come when we have more data that situation may change but for now realclimate is right, journalists when they do not know should not tell.

    Comment by pete best — 31 Oct 2006 @ 12:04 PM

  4. The BBC seemed to do a better job:

    Comment by Ed Hawkins — 31 Oct 2006 @ 12:28 PM

  5. Re #4: The BBC article quotes Professor Bryden (emphasis added):

    Professor Bryden, from the UK’s National Oceanography Centre, was the lead author on a paper published in the journal Nature last year that suggested the overturning circulation had declined by 30% over the past 50 years. That was based on a snapshot of data from the array.

    The findings were based on five historical “snapshot” measurements of overturning in 1957, 1981, 1992, 1998 and 2004.

    “The issue was how big was the variability in the five snapshot measurements, and that was something we needed to know,” he said.

    Using the first year’s data from the array, the researchers were able to adjust their calculations.

    “We concluded that there was some evidence of a small decrease but not as big as we reported in the Nature paper last year,” Professor Bryden observed.

    But we have had a decrease… in the order of 10% of the overturning circulation in the past 25 years.”

    By the way, the notorious sci-fi fantasy movie The Day After Tomorrow featured an array of ocean temperature / salinity monitors in the North Atlantic just like this one, and in the movie it was sudden anomalous readings from those instruments that alerted a somewhat Professor Bryden-like scientist character that catastrophic changes were imminent. I wonder whether the filmmakers based that part of the film on the actual RAPID research program or did they just make something up that had a coincidental similarity?

    Comment by SecularAnimist — 31 Oct 2006 @ 1:41 PM

  6. Here is an animation of the Gulf Stream – the Atlantic Thermohaline – over a two year period.

    It is not exactly chaotic, but you would need measurements over very long time scales covering most of the Atlantic at various ocean depths before you could really say what was happening.

    Comment by Jeff Weffer — 31 Oct 2006 @ 1:44 PM

  7. Heh, this website doesn’t seem to have of the basic info. There doesn’t seem to be a map of where the moorings are located, a picture of the mooring, etc. Heck I can’t even find a list of the number of moorings.

    Am I right in that this website is lacking or am I just blind?

    [Response:Try: -gavin]

    Comment by wacki — 31 Oct 2006 @ 1:53 PM

  8. From what I can see in the satellite images, e.g. NOAA SST Anomolies, the flow volume has, perhaps, not changed in the North Atlantic/Arctic ocean, but the turnover point has definately moved north – the blue areas to the north west of Asia look to be areas that were previously ice and are now an ice/sea water mix that is a bit cooler.

    Comment by Ken Rushton — 31 Oct 2006 @ 1:54 PM

  9. I wonder why?

    OPEC says British climate change report “unfounded”

    Britain to push for global climate deal by 2008,,1935552,00.html?gusrc=rss&feed=1

    Comment by lars — 31 Oct 2006 @ 2:02 PM

  10. I guess one could argue whether a 10% decline in the overturning circulation in the past 25 years was “dramatic” or not, but from the perspective of a person living in England, I guess it could be. In any case, I’m not about to quibble with the term.

    I didn’t find the Guardian article particularly offensive or alarmist. From my experience it is just about what science editors want from their reporters when faced with dramatic circulation decreases in newspaper readership. (I didn’t mean this as a pun, but perhaps it is. In any case, it might explain why a reporter sees a 10 percent decrease as “dramatic.”) The story is simply told from a particular point of view. Granted, from the point of view of someone who had seen the movie The Day After Tomorrow, but I bet this applies to a number of Guardian readers. I prefer the BBC article, too, but I doubt the BBC cares as much about circulation (as in “newspaper”) as the Guardian.

    We shouldn’t be too hard on newspaper science reporters. There are damn few of them left, and the trend is not in their direction. Who thinks working with the entertianment reporter is going to be any easier once they are gone?

    [Response: Your point is well taken. The issue here is really the signal-to-noise ratio. A potential 10% decline (2 Sv) is clearly within the sampling error of the data – thus no clear conclusion can be drawn. After another few years of monitoring we might be able to say something, but given the other evidence (different arrays, SST, water mass properties) that nothing that unusual is going on (so far), the balance of evidence suggests little or no trend. With respect to newspapers and reporting, I am usually a big fan of the Guardian and they generally do a good job – but it’s cruicial to get the right context, and blogs like this can help both lay readers and journalists to get a better grip on that. If we criticise this, it’s because we expect that they can do better. By contrast, we’re not bothering to critique the Daily Mail piece by Melanie Griffiths yesterday because that was just rubbish, and we’ve got no expectation that they are interested in doing better. – gavin ]

    Comment by David Fanning — 31 Oct 2006 @ 2:22 PM

  11. The newspaper business, especially now days, is a tough business. Newspapers don’t get sold with the hypercautious version of events that scientists often tell. People who buy newspapers want drama. Certainly the possibility of an ocean current stopping, and leaving Europe much colder provides such drama. It is also why one should read newspapers with a lot of skeptism, as this Guardian story illustrates. They are often more entertainment for the masses than carefully written acccounts of events: in other words, they come close to being fictional accounts with just a shred of truth in them.
    This is not all bad, of course. Without the drama, people will not get excited about global warming and its sometimes counterintuitive consequences. We need people to be concerned. It is also true, however, that to maintain the credibility of the scientific community, we do need to point out when newspaper stories run seriously amiss.

    Comment by Gene Hawkridge — 31 Oct 2006 @ 2:31 PM

  12. re. 1 “Ah, you scientists and your….science”

    Please draw three things from this article.

    1). Real scientists openly disclose their findings, no matter what the potential ramifications.

    2). A solid consensus exists and has existed for years now that global warming is happening (Unlike the conveyor belt slowing up in the long term), and that humans are causing a large part of global warming and that we are most likley in deep doo-doo if we don’t so something to stop global warming.

    3.) Messy scientific studies, like this MOC one, must first be debated, analyzed and tested before a consensus is reached. This is a seemingly messy study (to the public) but is necessesary to reach eventually, hopefully, a consensus on whether the meridonial overturning circulation (MOC, ocean conveyor belt, thermohaline, etc.) is indeed showing long-term slowdown or not.

    Comment by Richard Ordway — 31 Oct 2006 @ 3:01 PM

  13. I don’t know where else to post this comment, so I’ll try here…

    Can anyone at please respond to this article?

    The author challenges Gavin Schmidt by name.

    [Response: That’s pretty confused. He neither understands the physics of CO2, nor the implications of the Vostok record, nor the concept of positive feedback. We’ve discussed each of these issues before, and I would refer you there. – gavin]

    Comment by rocky collins — 31 Oct 2006 @ 3:08 PM

  14. Gavin’s account of the meeting and my letter in the Guardian are not ment to offend the maybe declining? species of science reporters. I know this is not easy and I don’t expect that articles should be just pleasing to the scientist, debate is good and heatly. What I objected to was the selection of the most speculative part of one talk at the meeting and setting it into an ‘alarmist’ context by quoting words from an obvious non expert, who apparently was not even aware of beeing “interviewed”.

    What was actually shown was a change in one part of the deep flow that could have been more than made up by a stronger transport in a shallower layer or further into the ocean away from where the current meters where. These are actually quite common phenomna that have been seen in several similar boundary current arrays at other places along the so called deep western boundary current. So initself this is not even “dramatically” new. But such an explaination could have been provided by an expert in field, if they would have been asked (several were at the meeting speaking in the same session….).

    Maybe some exageration is needed to make a story interesting, but is this really also true for the science page of a what I was told is a respected paper?

    I was also told by the reporter that one aspect of the story was cut by his editor that had set the Bryden Dec 2005 result into the variability perspective… so why was that cut and not the 10 day apparent halt? The answer is simple: Variability of climate is much less interesting that the possibility of a dramatic change event…

    And from a selling the paper point of view this is hard to argue with… we get told the news we want to hear. No offense but that is exactly what comment #1 was telling us… but please don’t abuse the science section of a paper for such speculations.

    Comment by Martin Visbeck — 31 Oct 2006 @ 3:26 PM

  15. I sympathize with Martin Visbeck’s point of view regarding what goes into the newspaper. I really do. But having decided to break out of my own little scientific niche and moonlight as a reporter for my local radio station I am beginning to see (and appreciate) the other side of the coin.

    I recently attended a tamarisk conference. Tamarisk is an invasive species of tree and is said to consume massive amounts of water as it out-competes native vegetation in riparian habitats. A big deal in the part of the world I live in. I diligently read the conference program and abstracts of the talks and posters before I arrived, but I didn’t know this crowd, and it was EXTREMELY hard to know who the “experts” were. In fact, everyone, including me, was wearing the exact same badge. (It would really help if the experts would identify themselves with a gold star or something! :^)

    Faced with a deadline, I did what I could. I tracked down a conference organizer and asked who the honchos were. He pointed out a few of them, and gave me the names of a few more, most of whom I couldn’t find at the breaks between sessions, so I never did end up interviewing them. I got some tape, but the story, from what I could tell, was that tamarisk actually use about as much water as the cottonwoods we use to replace them. (The extremely high figure everyone cites was a wild guess someone pulled out of the air years ago and had no scientific basis.) Not the sort of thing our listeners (as represented to me by my editor) really wanted to hear, apparently. The story exists only on my computer.

    My point is this. Being a diligent science reporter isn’t enough. Stories have to be sold. To your editor, to the public, to the advertisers who keep the paper/radio/magazine on the air. As scientists, we need to think about this and help the poor science reporter do his or her job. Don’t blather on, as one “expert” did about the nuances of how shade affects the succession of plants found in the vicinity of tamarisk. I’m sure it’s a great research topic. But I need four minutes of something exciting in about three hours and that dunderhead over there by the cannoli talking about the “idiots at the BLM” is looking more and more interesting to me!

    [Response: From what I’ve seen of the best science reporters, they tend to build a base of people who they trust to get things right and who don’t have personal agendas. Ideas then get bounced around them and interesting (and credible) experts on specifc topics suggested. Since this takes time, it isn’t always available for newbies or reporters for whom this isn’t their usual beat – thus assessment reports from IPCC or NAS, or blogs like this (potentially) must serve instead. As for some scientists’ inability to talk to journalists at an appropriate level, that is something you only get better at with a lot of practice – and most of us don’t get that much practice. -gavin]

    Comment by David Fanning — 31 Oct 2006 @ 4:56 PM

  16. Readers may wish to know that the RAPID website is at

    Nick Riley

    Comment by Nick Riley — 31 Oct 2006 @ 5:23 PM

  17. Gavin writes:

    As for some scientists’ inability to talk to journalists at an appropriate level, that is something you only get better at with a lot of practice – and most of us don’t get that much practice.

    My mother used to tell me that with a little attitude adjustment I wouldn’t mind piano practice so much. I wonder if the theory applies here, too. Less distain and more sympathy, like a lump of sugar, makes the medicine go down. :-)

    Comment by David Fanning — 31 Oct 2006 @ 5:36 PM

  18. Re #13: Gavin is being nice. Your rocket scientist does not even seem to understand basic accounting:

    Since the industrial revolution, man has been dumping CO2 into the atmosphere at an accelerating rate. However the measured increase in the atmosphere amounts to only about half of that manmade CO2. This is what National Geographic called, �The Case of the Missing Carbon�. Climatologists claim that the increases in CO2 are manmade, notwithstanding the accounting problems.

    OK, so I put 100 bucks a week into my bank account, but it only grows by 50 bucks a week. I may have an “accounting problem”, but are you going to tell me that the 50 bucks that is left does not come from me at all, but is a weekly gift from the bank?

    It is not rocket science.

    Comment by Blair Dowden — 31 Oct 2006 @ 8:30 PM

  19. The movie got more similarities… to bad its like the same scenario.

    (Science warns and politic does nothing than catastrophic event and all act (panic). Than with time they figure its to late to prevent catastrophic climate change. Well the plot takes place during the panic phase — becoming aware of uber changes. The solution was to go to mexico, though a part 2 movie would feature americans in mexico. Without anything. )

    How high is the chance that other species encounter exactly the same problems with a planets climate change — leading to unnatural global warming — antrophogenetic global warming?

    How high is the chance, we ride into the chaos and only a few breeding pairs will be left at the poles and eg. 95% of life extinct, as happend in earlyer events of natural gw?

    How high is the chance, that we will limit ressources per person and change limited engery(fossil) to renewable energy?

    There are many ways on the pathway to a planet which is habitable and has a big human population on it.

    The best way i think is, to regulate systems. And this will not work while nations act in diffrent ways, it will only work when all team up, as its a global threat. And it will only work if ppl change their godly lifestyles (comsumeing and not renewing).

    It will only work if we change the way we use energy global, and this can be only made in numbers by the biggest polutioners.


    Comment by savegaia — 1 Nov 2006 @ 1:24 AM

  20. I recently heard a talk by one of the authors of the ICES Report on Ocean Climate. You can find the most recent annual report here: .

    She explained that there were a lot of uncertainties about any changes in the ocean circulation, but that the one clear trend over the past few decades was warming and increase in salinity in the surface waters, particularly in the far north. The way I understood her talk (and sorry if I didn’t pick it up right!) it suggested that the much-reported long-term freshening in the northern North Atlantic was only found in the deeper waters, not close to the surface. She also said that her team had previously found an apparent weakening in the deep water circulation between Shetland and the Faroes, but that an overall weakening of the circulation was not consistent with the much clearer trend towards greater warmth and salinith in the far north.

    Does my summary of what I understand the ICES findings to be sound similar to what the RAPID conference discussed? As a lay person, this actually sounds like a strengthening of the overturning circulation (and the extra warmth which that would bring to the northern latitudes sounds pretty scary in its own right), although I must stress that this is not a statement which the speaker I heard made.

    Comment by Almuth Ernsting — 1 Nov 2006 @ 4:26 AM

  21. Yes, I first heard about the “dramatic ceasing” of this North Atlantic circulation the afternoon in a discussion here on the radio, when a New Zealand blogger, media commentator and keen supporter of the need to deal with global warming, Martyn “Bomber” Bradbury, used this information to back his thesis and support the sort of action needed following the Stern report. You can hear his comments here on the Radio NZ site for the next seven days.

    I was quite concerned to hear his using of this information “The Stern report is remarkably optimistic … could be a lot worse…. the North Atlantic COMPLETELY SHUT DOWN FOR TEN DAYS last year. It shut off for ten whole days. That’s crazy. If this current shut off altogether, the whole northern hemisphere would be plunged into an ice age. That’s the climate concern…. within a ten year period”. I have posted here previously about the way global warming deniers can twist and misuse scientific information. It is really important that people who are genuinely concerned about global warming don’t fall into the same trap in a misguided effort to reinforce their arguments in debates with others. The science of anthropogenic global warming is actually very robust, and becomes more so with each passing year. We don’t need contentious findings taken out of context to support our thesis. Hence this realclimate site of course. Bomber Bradbury was reasonably criticised by the other commentator on the programme for being unduly alarmist and a harbinger of doom. She was right to do so.

    What is concerning is that a so-called quality newspaper should have to resort to such simplistic headline grabbing reports to “sell a story”. It says a lot about the commercial imperatives that drives so much of the media, and the problems our society is going to face in debating and dealing with the real issues, if we can’t access sensible information from the popular and quality media, or that good science can so easily be trivialised and distorted.

    Did the scientists presenting this data spell out in words of single sylables, on at least several different occasions, that this information is new, that the variation in circulation discovered is more than expected and that no conclusions in regard to global warming can be drawn, nor should they be. And if not, why not? Have they, or will they, write to the Guardian, pointing out the paper’s misinterpretation of the actual data and it’s insupportably alarmist tone.

    Comment by John Monro — 1 Nov 2006 @ 4:33 AM

  22. “Since the industrial revolution, man has been dumping CO2 into the atmosphere at an accelerating rate. However the measured increase in the atmosphere amounts to only about half of that manmade CO2.” It’s dishonest to argue that this is in any way a problem for the greenhouse effect thesis.

    That thesis certainly includes the fact that warming causes additional carbon release and triggers processes that absorb more CO2 than previously. For instance, warming in the Arctic releases previously frozen CO2 in melted permafrost and melts frozen CH4, but global warming also stimulates plant growth and especially algae growth which absorbs CO2. If the stimulus to the plants causes them to absorb more CO2 than was released by melt or other physical reactions, then, that explains the so-called discrepancy. But it doesn’t mean that the land-based plants can keep doing it – especially not if they suffer drought, wind damage, fire or flood due to other effects of the warming atmosphere. It’s hard to see how the sea-based plants would stop though.

    Comment by Craig Hubley — 1 Nov 2006 @ 5:12 AM

  23. Thanks for the update, Gavin.

    Comment by Chip Knappenberger — 1 Nov 2006 @ 11:15 AM

  24. She explained that there were a lot of uncertainties about any changes in the ocean circulation, but that the one clear trend over the past few decades was warming and increase in salinity in the surface waters, particularly in the far north. The way I understood her talk (and sorry if I didn’t pick it up right!) it suggested that the much-reported long-term freshening in the northern North Atlantic was only found in the deeper waters, not close to the surface. She also said that her team had previously found an apparent weakening in the deep water circulation between Shetland and the Faroes, but that an overall weakening of the circulation was not consistent with the much clearer trend towards greater warmth and salinith in the far north.

    From wikipedia:
    The thermohaline circulation (THC) is a term for the global density-driven circulation of the oceans. Derivation is from thermo- for heat and -haline for salt, which together determine the density of sea water. Wind driven surface currents (such as the Gulf Stream) head polewards from the equatorial Atlantic Ocean, cooling all the while and eventually sinking at high latitudes (forming North Atlantic Deep Water). This dense water then flows downhill into the deep water basins, only resurfacing in the northeast Pacific Ocean 1200 years later[citation needed].

    Dr. James Hansen says it takes up to 1000 years till the ocean heat up from gw, as human greenhouse gases are excelarating at the fastest rate ever recorded (in compare to planets history climate events.). The point is, once the ocean reach a tipping point from heat up — methan sailed in ocean sediments will bubble up to the surface and than trigger an massive methan push into the atmosphere — such event would bring more greenhouse gases (methane levels) which gives global climate a major shift.

    Comment by savegaia — 1 Nov 2006 @ 12:57 PM

  25. Just for clarification – when you say ‘the variations day by day varied by around 5 Sv’, do you mean that the difference between consecutive measurements was up to 5 Sv, or that the calculated flow fell within a 5 Sv range over the whole measurement period?

    [Response: The latter. By eye I’d estimate that the variability was happening mainly at multi-day timescales, so you could have big swings over a couple of weeks or so. – gavin]

    Comment by gengar — 1 Nov 2006 @ 1:42 PM

  26. First we have William quoting The Clash, then Gavin disinterring Simon & Garfunkel (The Boxer). What next? Mike channeling Burt Bacharach? Stefan travelling down Kraftwerk’s Autobahn?

    [Response: We’re just trying to demonstrate how in tune we are with the zeitgeist…. (admittedly, the zeitgeist of the 1970s, but it’s a start!). Kraftwerk’s ‘The Model’ would have been a better choice for Stefan though! – gavin]

    Comment by Gareth — 1 Nov 2006 @ 3:19 PM

  27. Dear John Monro

    You asked:

    “Did the scientists presenting this data spell out in words of single sylables, on at least several different occasions, that this information is new, that the variation in circulation discovered is more than expected and that no conclusions in regard to global warming can be drawn, nor should they be. And if not, why not? Have they, or will they, write to the Guardian, pointing out the paper’s misinterpretation of the actual data and it’s insupportably alarmist tone.”

    I did write a letter and it got published.. and I know of a second letter that was sent from Bruce Warren of Woods Hole to the Guardian. But not all papers have the ability to publish all those letters. They have to pick and choose. Furthermore such letters receive less attention than the alarmist story did. Part of the issue is that (environmental) science is only in a very few cases clear cut. So stating in “single sylables” that the ocean circulation is not changing would be just as dishonest as saying it did. What we can say is: in most all places we were able to look carefully the chages are smaller than the “natural variability”… that is an honest statement but not BIG NEWS… plus it is hard work and costly to make those measurements so we have done it only in a few places …

    I hope that sites like REALCLIMATE can provide a forum for non experts to at least get a feel for the state of debate… and where important NON NEWS can become relevant information for the interested.

    Comment by Martin Visbeck — 1 Nov 2006 @ 4:59 PM

  28. Martin,

    Thanks for your reply – much appreciated. In my comments about the scientists saying things in single sylables, I was being facetious, which isn’t always easy to convey in print, perhaps I should’ve used a smiley! I know you don’t say things quite like that. But sometimes I wonder if the press aren’t like children, they only hear exactly what they wish to hear, and not to be misquoted you just have to be so pedantically careful, hence my comments, journalists seem to need to have things exactly – spelled – out – for -them. Also, I didn’t actually say that scientists shouldn’t say that the ocean circulation isn’t changing, I actually said “that the variation in ocean circulation was more than expected and that no conclusions in regard to global warming can be drawn”. I think this statement is fair? The problem is for you, I imagine, that global warming sceptics will now be flinging what they regard as your alarmist position back in your face, even though it wasn’t you at all.

    But I am pleased you were able to get one letter published, but as you say, correspondence doesn’t get anything like the same prominence as the original, and mischievous, article. I don’t live in the UK, and I don’t read the Guardian, so unfortunately I haven’t been able to read your letter either.

    Comment by John Monro — 2 Nov 2006 @ 3:45 AM

  29. What this discussion has not yet touched on is that the Guardian story was actually framed by referring to the incorrect and widespread assumption that ocean currents are the main cause of Europe’s relatively mild winters:

    “Scientists have uncovered more evidence for a dramatic weakening in THE VAST OCEAN CURRENT THAT GIVES BRITAIN ITS RELATIVELY BALMY CLIMATE” (emphasis added)

    This ‘myth’ has been analyzed by Richard Seager in the Journal of the Royal Meteorological Society and described in a more popular story here:
    and also here:

    So, it’s ironic…if ‘The Guardian’ wasn’t framing their story based on a popular incorrect perception in the first place then they probably wouldn’t report on a conference like this at all. Instead all this would just be a scientific curiosity boring to the layperson and not likely to make it into the newspapers.

    [Response: You are misreading Seager’s work. His claim is not that the THC doesn’t impact Britain and Europe, but that it isn’t responsible for the difference in temperature across the Atlantic. Not the same thing at all. -gavin]

    Comment by George Roman — 3 Nov 2006 @ 1:18 AM

  30. Regarding Martin Visbeck in #14, I suspect it’s not that variability was less “interesting”, but that the editor has a POV that must be served for a fact to make it into his paper.

    After reading a recent article in the New York Times on the paucity of research investment into CO2 abatement and alternative fuel technologies, I e-mailed the writer to inquire about his exclusion of a mention of the algae-to-biofuel research that is being conducted by several companies using private funds. The goal of these companies is to treat CO2 at the source as food for algae grown in bioreactors.

    At least one of the companies has reported that they have been able to measure a 40% reduction of CO2 at their test site on the MIT campus. This sort of reduction, if credible and scalable could result in the production of enough biofuels grown off the exhaust of the coal and natural gas power plants in the US to replace all of the current petroleum consumption by the US.

    This is the response I got: “we tried to focus this piece on options that can be done at scale sufficient to avert 10s of billions of tons of emissions. unless i’m mistaken, direct absorption at a power plant cant’ come close to handling that scale”.

    40% reduction would seem to contradict his conclusion, or would had he done any reporting…

    But his agenda was revealed when he continued: “we don’t want to imply something is a big part of limiting climate impact if it can’t (partic
    because that might cause readers to ‘relax’ a bit and think the whole thing is solved.”

    The piece he wrote was littered with technologies that will never be a “big part of limiting climate impact”, but they all had the commonality that their limitations were so obvious that it was clear to any reader that there is no solution, except to increase spending on “research” into dubious ideas.

    So there you have the explanation both for the content and tone of both the Gruniard piece and the Times piece. The points of the articles are less to inform opinion than to drive it.

    Comment by Michael May — 3 Nov 2006 @ 12:40 PM

  31. Re #13 and #18:

    I see that my name was used (without my knowledge) in the same article. I think that the main error the author made is using the pre-industrial correlation between temperature (as cause) and CO2 (as effect) to explain a no-effect of CO2 since the industrial revolution (as cause) on temperature. Further, the “missing sink” meanwhile is found in increased uptake by land/ocean biota (which gives less O2 change than calculated from fossil fuel use and land use changes).

    While in most cases there is an overlap between temperature changes and CO2 changes in the Vostok ice core, the effect of a ~40 ppmv CO2 change on temperature at the (non-overlap) first dip of the last ice age is small (non-detect in the temperature proxy). This may indicate a rather small influence of CO2 on temperature (at or even below the low side of the IPCC 1.5-4.5 K range for 2xCO2).

    At the other side, it is quite sure that the increase of CO2 in the atmosphere is from human emissions, there are a lot of indications for that (d13C ratios and CO2 levels in air and upper oceans, O2 levels in the atmosphere and pH of the oceans), which exclude other sources than human emissions. And last but not least, the fact that the change of ~1 K in global (ocean) temperature since the LIA can not give more than a 10 ppmv CO2 increase, if the Vostok temperature-CO2 correlation still holds, while in the same period the measured (ice core) levels increased with 60-70 ppmv…

    Comment by Ferdinand Engelbeen — 5 Nov 2006 @ 2:41 PM

  32. Given this work by Richard Seager and David Battisti:

    Couldn’t we be a bit less worried about MOC slowing?
    I guess this will still have impact on climate, but not the doomsday scenario we hear so much about.

    Comment by Alon — 6 Nov 2006 @ 4:46 AM

  33. Hello!!!!

    How can yiu be alarmed with out knowing what´s normal. Maybe the current pause all the time. If you have not bin messuring in the past how the hell should you know then.

    Comment by olle w — 6 Nov 2006 @ 8:30 AM

  34. Re: Gavin’s comments and #32

    Please note that Seager’s comments in the American Scientist hark back to his earlier work with Battisti. Their analysis used a model which did not include a computed model of sea-ice, instead proscribing a seasonal cycle based on historical areas. They compared this model with an earlier model experiment which did include sea-ice, which suggested an increase in the area of sea-ice in the North Atlantic Sub Polar Gyre. The model which included the impact of increased sea-ice due to a shutdown of the THC produced much cooler conditions over Northern Europe. Projections based on experiments without a dynamic se-ice model are likely to be inaccurate, IMHO.

    As an example, consider that there is data which points to a freshening of the Sub Polar Gyre. (see the link at comment #16 for the abstracts of the conference). At the same time, we now learn that the flow thru the Faroe Bank Channel has exhibiting an “substantial increase” in salinity (1). The implications of this change might be that the recent increase in yearly cycle in sea-ice extent (2) may be producing more salinity induced THC as brine is rejected below the new sea-ice. This process is different from what has been seen in past years and the location of the sinking may be shifting from the Greenland and Labrador Seas to the Barents Sea. If so, it might be expected that the minimum extent of sea-ice will decline even faster as more warm water flows into the Arctic Ocean below the sea-ice to replace that water which sinks.

    Just last August, there was a noticeable change in the ice to between the North Atlantic and the North Pole, as reported by the ESA (3). And, we learned a few days ago that the Northwest Passage was much easier to traverse this October than in pervious decades (4).

    1. Theme 1 Poster No. A11. “Faroe Bank Channel overflow 1995 – 2005”,
    B. Hansen, S. �sterhus, D. Quadfasel.



    4. “Melting Arctic Makes Way for Man”, Washington Post, 5 November 2006.

    Comment by Eric Swanson — 6 Nov 2006 @ 11:21 AM

  35. The oceans affected by naval and merchant ships operating and sailing the seas back and forth should have been the hottest topic in the debate on climate change since meteorology was established as a science in the late 19th century. Instead of that, oceans were ignored up to the late 20th century and not even today do they enjoy the significant position they deserve. Oceans are a decisive climatic force, the second after the sun.
    I emphasize with the idea that Naval War had a great impact in the climate change. I suggest visiting this thesis

    Comment by Angi — 7 Nov 2006 @ 10:46 AM

  36. Gavin. I don’t see why you are so shocked. We could find thousands of similar examples of the media reporting a story inaccurately.

    Comment by HGH — 7 Nov 2006 @ 2:25 PM

  37. Richard Kerr from Science Magazine has picked up the story this week…

    Comment by Martin Visbeck — 17 Nov 2006 @ 1:01 PM

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