Monday, December 31, 2012

Science of the day: 1st year ice lets light through


Wow, this is cool. H/t Felicity Barringer at the New York Times.

I find these sorts of papers delightful because they take a problem that has engaged many brilliant people -- Why is the Arctic melting faster than climate models suggest it should? -- and suggest a simple correction, backing up that intuition with data.

In this case, the powerfully simple idea is ice is not totally opaque. As anyone who has ever looked at a piece of ice knows, thin ice lets more light through, thicker less. So with the aid of sensors under the ice, the authors have shown that the thinning of the ice sheet, the melting and re-freezing, under global warming, results in more thin ice and less thick ice. Boom! Another positive feedback; more energy is absorbed, the Arctic warms fast and the ice melts faster.

Seems almost too basic, doesn't it? Elegant idea, elegant demonstration.


Saturday, December 22, 2012

Reforestation as carbon sequestration

Source.
In my previous post, I suggested that geoengineering might not have to persist continuously for thousands of years, if solar radiation management were used, not as a "destination therapy" but as a bridge, in combination with intensive mitigation, until a realistically slow program of carbon sequestration could take effect. How the carbon might be sequestered wasn't discussed. Chris Reynolds offered offers some options (from the relevant Wikipedia page):


  • Creating biochar (anaerobic charcoal) and burying it to create terra preta
  • Bio-energy with carbon capture and storage to remove carbon and simultaneously provide energy
  • Carbon air capture to remove carbon dioxide from ambient air
  • Ocean nourishment including iron fertilisation of the oceans

  • All of which have land use or energy input requirements. Clearing more land would place more pressure upon ecosystems, or food prices. Any energy used would have to be non fossil fuel, which would eat into whatever offsets could be made to fossil fuel burning reductions. Overall the whole process would have to not impact the poor (food prices), and would have to be substantial.
    Obviously a tall order. But is there perhaps a way around some of these requirements, a way to sequester carbon without clearing more land, putting more pressure on ecosystems, or investing a lot of (our own) energy? It turns out there is!

    Simple reforestation could sequester 3Gt/year of CO2. In fact, simply halting deforestation (18% of current emissions * 33Gt = about 6Gt of CO2 per year) would more than do the trick. But since we are eventually going to have to push our emissions near net zero anyway, the gain from halting deforestation is already "baked in" to the mitigation scenario (which was to leave us with 1,200Gt in net emissions including carbon-cycle feedbacks.) But what is not baked in is adding back forest cover.

    Obviously this would be a slow and difficult process. It would involve increasing housing density, abandoning uneconomic farms and ranches (a disastrous hobby of rich governments the world over; the price tag for agricultural subsidies in 2011: $252 billion)) and growing food more efficiently on the land that remains. It might mean more expensive meat, tilting our diets towards more grains and pulses. But the potential gains are substantial. In fact, they are sufficient:

    "The woody biomass of forests is estimated in
    this paper to contain 300 × 10^9 tons carbon. For
    comparison, the cumulative emissions from the
    combustion of fossil fuels in the 19th and 20th
    century were about 280 × 109 tons. In 2000, the
    atmosphere contained about 790 × 109 tons in
    CO2 (Enting et al. 2001, Marland et al. 2002)."

    -- "New, Low Estimate for Carbon Stock in Global Forest Vegetation Based on Inventory Data"

    About 30% of the world's forest cover has been lost in the last two centuries, since the Industrial Revolution. Taking the conservative estimate of the forest biomass quoted above, restoring the world's forests to their extent a few centuries ago could trap at least 126Gt of carbon, which is the equivalent of about 462Gt of CO2 -- a hair more than I said we needed to get back to a reasonable atmospheric CO2 level and stop solar radiation management.

    I'm not sure why reforestation didn't make Chris' list, above. It does have a prominent place on the wikipedia page for carbon sequestration, but not for carbon dioxide removal. Just speculating, I think one might overlook the obvious potential of reforestation because it so obviously is very slow, and would be completely unable to cope with the BAU emissions expected in the 21st century. Once again, there is a critical difference between looking at geoengineering as cure (hopeless and stupid) and looking at it as one element of an intensive program to keep the world under 2C, with its specific role being to buy a little time.

    Wednesday, December 19, 2012

    Does geoengineering have to continue for thousands of years?

    Cloud whitening, one geoengineering strategy

    Chris Reynolds at Dosbat expresses the basic pro-science critique of geoengineering:
    With the seriousness of the situation regards AGW becoming more clear, talk of geo-engineering has increased. I think that rather than try to stem population increase, examine our economic system and expectations, and reduce CO2 emissions, this will be seen as a viable option in the years to come.

    However geo-engineering will, I am confident, be used as an excuse to carry on emitting CO2 and avoiding dealing with the fundamental flaw in our civilisation; exponential growth in a finite world. It is dangerous and is a recipe for disaster.
    He may be absolutely correct on all points; the only parts I take issue with are the bolded ones (and the finite growth thing, a bit.)

    The first point, the "rather than," is one we have to confront on a regular basis with the adapt-nik ("Don't mitigate -- adapt!) subspecies of lukewarmer. To wit: we can (and must) do more than one thing at a time. The resources required to investigate and prepare for the possibility that we may need to geoengineer are miniscule relative to mitigation, adaptation, or even population control.

    If we were only going to do one thing, it sure as hell wouldn't be geoengineering. But we're going to have to do more than one thing.

    The second point, that geoengineering may be used as an excuse to defer action, is a serious concern. Geoengineering would only work as a temporary bridge to allow intensive mitigation to bear fruit. But would it, actually, become an excuse for inaction?

    This is a different, and slightly more upbeat, counterargument compared to the related riposte: "We don't need an excuse for inaction; we're excusing it fine as it is." In that fatalistic outlook, geoengineering becomes like a clean needle program for heroin addicts: we wish we could fix the underlying issue; we can't; we're going for damage control.

    I am not such a fatalist; and I do not necessarily think that the availability of geoengineering will make mitigation less attractive. Consider, for example, how the adapt-vs-mitigate debate has unfolded (or failed to unfold) after Hurricane Sandy. Experts looking at the flood surge have suggested we could have prevented a large portion of the roughly $50 billion damages using $10-$15 billion dollars in floodgates. So my question is: Where are the adaptniks screaming for these new defenses?

    I was able to find a tepid endorsement from Bjorn Lomborg which radically lowballed the cost of said adaptation.
    Much of the risk could be managed by erecting seawalls, building storm doors for the Subway, and simple fixes like porous pavements – all at a cost of around $100 million a year.
    If you follow the link, it leads to an article from Popular Science which includes this:
    If New York—part of the Northeast megaregion—suffers a direct hit, workers will spend weeks pumping a billion gallons of brackish water out of its subway and train tunnels. The salt will corrode power lines, transformers and thousands of brakes and switches that control the trains. Some subsystems could take a year or more to restore.

    To avoid such a scenario, New York state recommends the city invest well over $100 million a year in storm protections. City planners are already experimenting with dozens of low-tech fixes, says Adam Freed, deputy director of the Mayor's Office of Long-Term Planning and Sustainability.
     Note "well over $100 million" not "around $100 million." And while the original source describes these "dozens of low-tech fixes" as merely able to mitigate the nightmare scenario, in Lomborg's retelling they eliminate "much of the risk."

    Lomborg also repeats the fallacy that the risks of a damage storm surge have nothing to do with climate change -- even though sea level rise, by definition, makes storm surges more destructive.

    And that tepid, dishonest, weasel-worthy endorsement was really about all we heard from the "adapt, don't mitigate" crowd after Sandy. Judith Curry had a guest poster make the pitch for more weather satellites. Lucia Liljegren, not a word. So why not pitch adaptation in this brave new world?

    My theory is, actual real-world adaptation makes the problem of global warming too real. It's one thing when "adaption" is an abstract concept describing something we may do in the future. But when it actually comes down to spending tens of billions of dollars on flood defenses, planned retreat from parts of the coastline, restoring wetlands, lowering levees, hardening the power grid, and beefing up the first responder network -- well, if you start spending that kind of money (hundreds of billions for starters, talking about the US alone), people might get to wondering why this global warming stuff is so gosh darned expensive and getting more so. And that might lead them to ask when we are going to stop adding to the bill by spewing billions of tons of CO2 into the air.

    Geoengineering might similarly offer the public some clarity on this issue. I assume it will be far more expensive that it currently seems, it will be highly controversial on the world stage, it will have unwanted side effects and limited efficacy. Researching and preparing such a system might have the opposite of the effect Chris expects; it might focus the public's mind on what a god-awful problem this is and how we need to get busy fixing it.

    If we research and prepare this tool (not deploying it until/unless we win an international consensus and after warming has crossed a specific threshold or we see evidence of rapid catastrophic feedbacks) the debate which ensues may, as Sandy has, stimulate the public and international debate on mitigation, so as to prevent or minimize the use of such desperate measures.

    Another major concern with geoengineering schemes is the impracticality of keeping them running for a long, long time:
    Why do I say we would need to keep up SRM for millennia?

    Archer & Brovkin's 2006 paper "The Millennial Atmospheric Lifetime of Anthropogenic CO2", PDF, shows that the emissions of CO2 will remain in the atmosphere/ocean system for thousands of years. Their abstract sums up their findings perfectly:
    The notion is pervasive in the climate science community and in the public at large that the climate impacts of fossil fuel CO2 release will only persist for a few centuries. This conclusion has no basis in theory or models of the atmosphere/ocean carbon cycle, which we review here. The largest fraction of the CO2 recovery will take place on time scales of centuries, as CO2 invades the ocean, but a significant fraction of the fossil fuel CO2, ranging in published models in the literature from 20–60%, remains airborne for a thousand years or longer. Ultimate recovery takes place on time scales of hundreds of thousands of years, a geologic longevity typically associated in public perceptions with nuclear waste.
    So if we take any geo-engineering scheme that doesn't involve massive emissions reductions or active draw-down of CO2, we need to keep it up for at least 1000 years, the more CO2 we emit the longer the recovery of CO2 back to pre-industrial will take.

    And if we falter...
    That's obviously a legitimate concern. There isn't a single government on the face of the Earth that has maintained its present form of government for even a single millennium. If we are expecting them to maintain a stable geoengineering scheme for thousands of years, that's obviously impractical. And since solar radiation management strategies mostly poop out within a few years of stopping, you confront the possibility of decades or centuries of global warming hammering the world in the space of a few years.
    Brrrrrrrrrr. I've scared myself. But perhaps the picture is not so dire. What if we look at geoengineering not as a mono-strategy, but, as I suggest, as one component of a threefold strategy of adaptation, mitigation, and geoengineering?

    Let's say we get serious about mitigation and end up with 1,200Gt of CO2 equivalent added to the atmosphere (either it took too long to forge agreement, or the cuts could not be made fast enough, or the carbon feedbacks hit us too hard; we missed the 1,000Gt goal for 2C, but only just.) About 60% of that shows up in the atmosphere; the rest is immediately taken up by the carbon cycle. 720Gt. That's us, permafrost melting, forest dieback, what have you.

    Let's say 50% of that remains in the atmosphere 300 years later. That's 360Gt. Meanwhile we are practicing some solar radiation management with cloud whitening and contrails and aerosols injected into the stratosphere. But we also have been doing some carbon sequestration.

    Carbon sequestration is hard: suppose we don't get it off the ground for 20 years and it then takes us 30 years to ramp up sequestration to a grand total of 3Gt/year (that's about 9% of current emissions). We then practice that for about 150 years. That would take out 450Gt, but some of that would have been sequestered anyway -- we will only count 2/3 of the 450Gt as actual sequestration -- 300Gt. 

    That leaves us with 60Gt above preindustrial -- about 330ppm of CO2 -- and we can probably stop spewing stuff into the sky at that point, the 200-year mark. Two hundred years is a very long time, but it is a lot less than thousands of years. Many governments have been more or less stable for 200 years, including the United States.

    The exact figures are subject to debate, but the basic thrust is clear: two ideas that seem impractical on their own (solar resource management and carbon sequestration) get much more reasonable if you intelligently combine them with each other and intensive mitigation. Without mitigation, none of this works: you're continuing to shoot holes in the bottom of the boat as you're bailing it out.

    Wednesday, December 12, 2012

    Geoengineering as Critical Care

    A smoking-cessation skeptic

    Suppose your grandmother comes into the emergency room with a severe pneumonia. Probably she should have gone to her doctor last week when she started with a wet cough and a low-grade fever, maybe a little short of breath, but she decided to tough it out. Now her respirations are shallow and fast, she is pale and sweaty, and the toxic byproducts of the bacteria in her bloodstream have stunned her heart, dropped her blood pressure and shut down her kidneys.

    She's dying. What do you want the ER doctor to do?

    The first option is to do what should have been done last week; prescribe some oral antibiotics, bedrest, lots of fluids. But while that's was right thing to do last week, today that therapy will accomplish exactly nothing, unless you put the nurse in your personal time machine and send him back to last week.

    So we are going to come at this a little harder; we are going to treat it like the emergency it is. IV fluids to correct dehydration, IV antibiotics to tackle the infection, supplemental oxygen to give a head start to her struggling lungs.

    But sometimes that doesn't work either. The blood pressure doesn't correct with IV fluids; other organs begin to fail; her lungs cannot maintain her body's oxygenation requirements, even with the supplemental O2. She is still breathing fast and shallow and now starting to have heart and liver dysfunction to go with the kidney failure.

    At this point your only option(*) is critical care. A breathing tube will do what her lung muscles no longer can. Vasopressive drugs will support her blood pressure. She may need supplemental electrolytes; she may need insulin to control an elevated glucose.

    An important fact to realize about critical care is that all of these interventions -- all of them -- are terrible for the body and fraught with life-threatening side effects. None of them are remotely as safe and effective as going in to see your family doctor when you(**) are coughing with a fever and shortness of breath. But, again, no time machine.

    Those vasopressors will clamp down your peripheral circulation and can cause skin ulcers, gut ischemia, maybe further cardiac damage. Intubation can lead to long-term respiratory failure, barotrauma (you put too much air in the lungs!), or oxygen toxicity. The IV fluids will leak out of the vessels and cause edema, and so on.

    Critical care -- all medicine, really, but especially critical care -- is a matter of trade-offs. We support your critical needs -- especially adequate and well-oxygenated blood flow to your heart and your brain -- at the expense of the normal, orderly functioning of your body. That makes them temporizing measures. Only an idiot would do these things and not also treat the underlying infection with powerful IV antibiotics. Without the antibiotics and functioning immune system, none of the other measures are likely to accomplish anything except to briefly prolong a painful death.

    Geoengineering is similar to critical care. It is absolutely inferior to timely mitigation. However we have not carried out timely mitigation, and are now sitting on a massive stockpile of melting permafrost and an inefficient economic system generating huge volumes of CO2 and other GHGs with a large amount of inertia. Even if we were to embark on an ideal program of mitigation today, we would likely end up over the 2C threshold.

    There is no point in geoengineering if we do not also intensively mitigate. It is bound to be at best a partial solution, with many side effects, and much more expensive than it looks on paper. Mitigation is like the antibiotics; the critical care in essence buys time for the real solution to work.



    -----------------------------------------------
    * Other than hospice, which doesn't really work with this metaphor.
    ** Grandmother/otherwise elderly you. If you're under fifty, it's probably just a cold, you big baby.

    Sunday, December 9, 2012

    The Signal and the Noise: the King of the Nerds on Climate Change

    Buy it now.
    This book fluttered the needle in the climate community already when Michael Mann expressed concern that not all was well with Silver's chapter on climate. Having read the book, Silver may not have everything right, but he's made a strong contribution to the world of reality-based thinking.

    It isn't so much what he has to say specifically on the subject of climate. He doesn't dig into that too deeply. What he is very concerned with is how we evaluate evidence, how we assess and make use of expert predictions and computer models both, and how we recognize the difference between serious prediction and entertaining spin.

    Relevant? I thought so. Here are Silver's main points, as I see them:

    1. Experts work better with models, and just as importantly, models work better with experts. Neither one is as strong as both of them together.

    2.Numbers don't speak for themselves. Without an underlying theory of what might be happening and why, you can't propose a reasonable pretest probability, and without a reasonable estimate of the pretest probability, you can't get much useful information out statistical tests of your data.

    I don't know if Silver has even heard the term "mathturbation." If he has, he's far too classy to make use of it. But he shows us in a very compelling way why statistical analysis without theory is useless in a Bayesian universe.

    3. In prediction, an average of many estimates from many different models and experts is typically better than just picking your favorite.

    4. Many predictions from self-described experts are made for entertainment value and should be judged as such. Professionals are not inherently better or smarter than amateurs, but they are less likely to be subject to perverse incentives that reward them for being grossly wrong over and over.

    Especially in our connected, information-rich world, the first task of a talking head is to call attention to their prediction -- to get noticed. That incentive favors extreme predictions, not accurate ones. A professional, however, who needs to maintain relationships with a smaller community paying closer attention over many years and many predictions, has a strong incentive to get things right. Which is one of the reasons we will not be replacing Nature with climate blogs any time soon.

    Michael Mann points out that Silver says some nice things about Scott Armstrong, a creepy statistically illiterate self-declared "forecasting expert." That guy makes my skin crawl, but as far as I could see Silver did not side with him and correctly dismissed his climate "bet" thought experiment as dubious.

    If you look away from the scant remarks on climate and look at how the larger argument applies to the climate debate, the points Silver makes are powerful arguments for the practices of the quote-unquote "climate establishment," and a devastating takedown of the "skeptic" argument.

    He shows why we need experts, not just blind data analysis. He shows that statistics in the real world depend on a reasonable estimate pretest probability, which (and this is a simple but powerful point) means that a clear theory of the underlying process -- not a vague appeal to "natural causes"! -- is necessary to make intelligent use of the data.

    Silver explains how the science of statistics justifies taking as many models and methods as possible into account when developing estimates of complex outputs like climate sensitivity and sea level rise.

    Finally, by dissecting the pundit model of prediction, where the little known and little remembered predictor/entertainer makes dramatic declarations and evades responsibility for mistakes, Silver strikes a rare and welcome blow for professionalism in a culture that sometimes seems to worship the amateur as a higher and purer source of insight. Professionals don't just know their stuff, Silver argues, they themselves are known, and valued, only as far as their predictions are more successful than not. This gives them a strong incentive to get it right that amateurs struggling to be noticed and political voices pushing an agenda simply do not have.

    Silver is worth reading, and I hope the valid caveats expressed by Dr Mann don't discourage pro-science voices from picking him up.

    Friday, November 30, 2012

    Adapt, Geoengineer, Mitigate (AGM)

    Source: National Research Council. 2011. Climate Stabilization Targets: Emissions, Concentrations, and Impacts over Decades to Millennia. p.101. Washington, DC: The National Academies Press
    So it's time to talk about geoengineering. Like it or not.

    The reality that a significant amount of carbon dioxide and methane are going to emerge from melting permafrost seems at last to be making an impression on the popular press (thanks latterly to a recent UN report). The implication, that it is extraordinarily improbable that mitigation alone will be able to limit warming to < 2C above preindustrial, does not seem to have sunk in yet, but the logic is fairly inescapable.

    Investigations of climate sensitivity continue to come back with values clustering around 3C/doubling. Based on those values, the total amount of CO2 that can be added to the atmosphere and still leave us with the hope of keeping warming below the 2C target is about 1,000 gigatons or a trillion tons. Total CO2e emissions to date are between 500 and 600 gigatons. Permafrost emissions by 2200 are estimated to be between 246 to 415 gigatonnes. Take the midpoints of both ranges and add them together and you get 880 gigatons. Right now the world is adding to that figure at a rate of 30 gigatons of carbon dioxide per year, plus sundry other GHGs.

    Even if you could instantly cut GHG production by 90%, you'd still cross the threshold within 40 years or so.  Any sort of a realistic program -- and in that I include a WWII-style crash program to cut emissions, consuming a significant chunk of the planet's GDP over the next few decades -- would come nowhere close to meeting the trillion ton target.

    Taking the most likely case -- that scientists' warnings continue to fall on deaf ears for at least a half a decade -- we will commit ourselves absolutely in four to five years -- perhaps less, if the world economy grows at a brisk pace.

    It's possible, of course, to stick with the party line despite the inevitability of crossing the trillion-ton mark. Emission cuts as fast as possible; adaptation; and hold on to something, because the 21st century is looking like a bumpy ride. But it is more in the spirit of climate realism to face the facts honestly and, where necessary, change our strategy.

    What are those facts? Fact number one: carbon-cycle feedbacks will put the 2C target out of reach through mitigation alone. Fact two: the severity of the climate impacts we are seeing at 0.8C above preindustrial suggests the 2C is a hard target. Two and a half times the warming we have seen to date is already, probably, outside any reasonable boundary of "safe" temperatures. Fact three: the Arctic permafrost is not the only game in town. There is also carbon under Antarctica. There are methyl hydrates. There is carbon locked up in the Amazon and other forests vulnerable to die-back.

    If you take the 2C limit seriously, you have to consider that the time may be approaching where we will need geoengineering as a bridge to lower levels of GHGs.

    Geoengineering has a bad reputation. People fear it as a quick fix, a barrier to the changes we need, and a long walk off a short pier into the Bay of Unintended Consequences. It has the potential to be all of those things. But it seems increasingly unlikely that we will get through the next two centuries in one piece without it.

    The AGM strategy has three elements:

    Adapt: Prepare our defenses and infrastructure for multi-meter sea level rise and the storms of the 21st century. Prepare our water resources for droughts, salinization, and flooding. Prepare our emergencies services, diversify our food crops, improve the robustness (and efficiency) of our infrastructure.

    Geoengineer: Start planning with small-scale tests now; larger-scale tests as soon as feasible; infrastructure for large-scale deployment as soon as we have a workable technology or set of technologies. Then set a hard upper limit well back from the 2C boundary -- like 1.5C, or at the first sign of a catastrophe like massive methyl hydrate degassing. At 1.5C over preindustrial, geoengineering kicks in.

    Mitigate: Agreement to severe and ongoing cuts in GHG emissions between a few large powers, with serious diplomatic and economic arm-twisting as necessary to enlist the rest of the world. Our goal should be to get back to 350ppm CO2e

    Could wildly successful geoengineering decrease the pressure for an agreement on serious mitigation? Sure it could. But you have to ask yourself if you believe the science.

    If you do believe the science, and understand that as we approach 2C our civilization and most of the species we share the earth with are in mortal danger, then while that perverse incentive matters, it can't be paramount, any more than the fear that people will eat too much and not exercise is a reason to not put a heart attack survivor on blood pressure and cholesterol-lowering medications. Yes, they have side effects. Yes, they are in some respects an artificial compensation for a failure in self-control. Nevertheless, letting the patient drop dead is a bad option. Better to use the artificial support, and continue to campaign for the lifestyle changes.

    Friday, November 9, 2012

    Could we see a triple-dip La Nina?

    Lately ENSO has been teasing us with a halting, stop-go flirtation with El Nino conditions. It certainly seems like we're due, given the preceding double-dip La Nina, something which, as I wrote last year, is already an unusual event. But then there's this:



    Really? Another La Nina? How weird is that?

    Actually it has never happened since NOAA started keeping records. Sixty years ago. Talk about your global weirding.

    NOAA still rates a weak El Nino as more likely than a return to La Nina conditions. But it's modestly amazing to me that a triple-dip is even a realistic possibility. Come what may, eventually we're going to see a strong El Nino again. The longer we wait, the more profound and record-shattering the ensuing temperatures are likely to be.

    Thursday, October 25, 2012

    Gulf Stream destabilizing methyl hydrates

    Thus Nature:

    The Gulf Stream is an ocean current that modulates climate in the Northern Hemisphere by transporting warm waters from the Gulf of Mexico into the North Atlantic and Arctic oceans1, 2. A changing Gulf Stream has the potential to thaw and convert hundreds of gigatonnes of frozen methane hydrate trapped below the sea floor into methane gas, increasing the risk of slope failure and methane release3, 4, 5, 6, 7, 8, 9. How the Gulf Stream changes with time and what effect these changes have on methane hydrate stability is unclear. Here, using seismic data combined with thermal models, we show that recent changes in intermediate-depth ocean temperature associated with the Gulf Stream are rapidly destabilizing methane hydrate along a broad swathe of the North American margin. The area of active hydrate destabilization covers at least 10,000 square kilometres of the United States eastern margin, and occurs in a region prone to kilometre-scale slope failures. Previous hypothetical studies3, 5 postulated that an increase of five degrees Celsius in intermediate-depth ocean temperatures could release enough methane to explain extreme global warming events like the Palaeocene–Eocene thermal maximum (PETM) and trigger widespread ocean acidification7. Our analysis suggests that changes in Gulf Stream flow or temperature within the past 5,000 years or so are warming the western North Atlantic margin by up to eight degrees Celsius and are now triggering the destabilization of 2.5 gigatonnes of methane hydrate (about 0.2 per cent of that required to cause the PETM). This destabilization extends along hundreds of kilometres of the margin and may continue for centuries. It is unlikely that the western North Atlantic margin is the only area experiencing changing ocean currents10, 11, 12; our estimate of 2.5 gigatonnes of destabilizing methane hydrate may therefore represent only a fraction of the methane hydrate currently destabilizing globally. The transport from ocean to atmosphere of any methane released—and thus its impact on climate—remains uncertain.
    A number of outlets have picked up on this story, and it's easy to see why. This is another classic we-thought-it-would-take-thousands-of-years moment. In recent years methyl hydrate deposits in the Arctic, and especially the shallow deposits in the East Siberian Arctic Shelf, have grabbed the spotlight. Another recent study made headline when it warned of large methane deposits under Antarctica. It seemed that methane was on the move North and South, and the poles grabbed most of the popular attention. But:


    Methane hydrates are over over the place. Including places in the ocean dramatically warmed by shifting ocean currents. So there's that.

    Key points from the study include:

    1. Methyl hydrate deposits are being destabilized by warming oceans right now.
    2. We don't know how much of this carbon will make it into the atmosphere, vs contributing to the acidification of the oceans.
    3. The study looked at part of the North American coastline, but this process is likely unfolding in other parts of the world as well.
    4. Reports of the death of the clathrate gun hypothesis have been greatly exaggerated. This is only one of many recent studies to illustrate that carbon-cycle feedbacks have the potential to add large amounts of greenhouse gases to the atmosphere. How fast? Not overnight, but not necessarily over thousands of years, either.
    5. With vulnerable carbon stores in the Arctic, the Antarctic, and on the continental shelves in between, it is becoming painfully clear that anthropogenic global warming is a game of Russian roulette played with a semiautomatic.

    Friday, October 19, 2012

    Climate deniers losing the argument

    Highlights
    • Americans’ belief in the reality of global warming has increased by 13 percentage points over the past two and a half years, from 57 percent in January 2010 to 70 percent in September 2012. At the same time, the number of Americans who say global warming is not happening has declined nearly by half, from 20 percent in January 2010 to only 12 percent today.
    • For the first time since 2008, more than half of Americans (54%) believe global warming is caused mostly by human activities, an increase of 8 points since March 2012. Americans who say it is caused mostly by natural changes in the environment have declined to 30 percent (from 37% in March).
    • A growing number of Americans believe global warming is already harming people both at home and abroad. Four in ten say people around the world are being harmed right now by climate change (40%, up 8 percentage points since March 2012), while 36 percent say global warming is currently harming people in the United States (up six points since March).
    • In addition, they increasingly perceive global warming as a threat to themselves (42%, up 13 points since March 2012), their families (46%, up 13 points), and/or people in their communities (48%, up 14 points). Americans also perceive global warming as a growing threat to people in the United States (57%, up 11 points since March 2012), in other modern industrialized countries (57%, up 8 points since March), and in developing countries (64%, up 12 points since March).
    • Today over half of Americans (58%) say they are “somewhat” or “very worried” - now at its highest level since November 2008.
    • For the first time since 2008, Americans are more likely to believe most scientists agree that global warming is happening than believe there is widespread disagreement on the subject (44% versus 36%, respectively). This is an increase of 9 percentage points since March 2012.
    This is a welcome reminder that the climate blogosphere is a tiny, tiny community, and the irrational, unpersuadable right-wing ideologues who relentlessly seek domination over it do not reflect the broader, disengaged public. Nor is the public responding to pro-science perspectives. If I had to guess, I'd say they are simply responding to the evidence that they are seeing with their own eyes.

    Saturday, October 6, 2012

    Three papers on the Antarctic ice



    There is a lot of carbon under that ice.
    Potential methane reservoirs beneath Antarctica Wadham et al (2012)
    Abstract: Once thought to be devoid of life, the ice-covered parts of Antarctica are now known to be a reservoir of metabolically active microbial cells and organic carbon1. The potential for methanogenic archaea to support the degradation of organic carbon to methane beneath the ice, however, has not yet been evaluated. Large sedimentary basins containing marine sequences up to 14kilometres thick2 and an estimated 21,000 petagrams (1Pg equals 1015g) of organic carbon are buried beneath the Antarctic Ice Sheet. No data exist for rates of methanogenesis in sub-Antarctic marine sediments. Here we present experimental data from other subglacial environments that demonstrate the potential for overridden organic matter beneath glacial systems to produce methane. We also numerically simulate the accumulation of methane in Antarctic sedimentary basins using an established one-dimensional hydrate model3 and show that pressure/temperature conditions favour methane hydrate formation down to sediment depths of about 300metres in West Antarctica and 700metres in East Antarctica. Our results demonstrate the potential for methane hydrate accumulation in Antarctic sedimentary basins, where the total inventory depends on rates of organic carbon degradation and conditions at the ice-sheet bed. We calculate that the sub-Antarctic hydrate inventory could be of the same order of magnitude as that of recent estimates made for Arctic permafrost. Our findings suggest that the Antarctic Ice Sheet may be a neglected but important component of the global methane budget, with the potential to act as a positive feedback on climate warming during ice-sheet wastage.

    That ice is melting faster than we thought it would.


    Dynamics of the last glacial maximum Antarctic ice-sheet and its response to ocean forcing -- Fogwill et al (2012)
    Abstract: Retreat of the Last Glacial Maximum (LGM) Antarctic ice sheet is thought to have been initiated by changes in ocean heat and eustatic sea level propagated from the Northern Hemisphere (NH) as northern ice sheets melted under rising atmospheric temperatures. The extent to which spatial variability in ice dynamics may have modulated the resultant pattern and timing of decay of the Antarctic ice sheet has so far received little attention, however, despite the growing recognition that dynamic effects account for a sizeable proportion of mass-balance changes observed in modern ice sheets. Here we use a 5-km resolution whole-continent numerical ice-sheet model to assess whether differences in the mechanisms governing ice sheet flow could account for discrepancies between geochronological studies in different parts of the continent. We first simulate the geometry and flow characteristics of an equilibrium LGM ice sheet, using pan-Antarctic terrestrial and marine geological data for constraint, then perturb the system with sea level and ocean heat flux increases to investigate ice-sheet vulnerability. Our results identify that fast-flowing glaciers in the eastern Weddell Sea, the Amundsen Sea, central Ross Sea, and in the Amery Trough respond most rapidly to ocean forcings, in agreement with empirical data. Most significantly, we find that although ocean warming and sea-level rise bring about mainly localized glacier acceleration, concomitant drawdown of ice from neighboring areas leads to widespread thinning of entire glacier catchments—a discovery that has important ramifications for the dynamic changes presently being observed in modern ice sheets.

    When that ice melted previously, global carbon dioxide levels rose dramatically over only two hundred years.


    Abrupt change in atmospheric CO2 during the last ice age – Ahn et al. (2012)
    Abstract: “During the last glacial period atmospheric carbon dioxide and temperature in Antarctica varied in a similar fashion on millennial time scales, but previous work indicates that these changes were gradual. In a detailed analysis of one event we now find that approximately half of the CO2 increase that occurred during the 1500-year cold period between Dansgaard-Oeschger (DO) events 8 and 9 happened rapidly, over less than two centuries. This rise in CO2 was synchronous with, or slightly later than, a rapid increase of Antarctic temperature inferred from stable isotopes.”
    Citation: Ahn, J., E. Brook, A. Schmittner, and K. J. Kreutz (2012), Abrupt change in atmospheric CO2 during the last ice age, Geophys. Res. Lett., doi:10.1029/2012GL053018.
    Comment: This is all very new science, but these three very different papers with different subjects and different methods seem together to suggest a coherent narrative; ocean warming rapidly triggers widespread decay of the Antarctic ice sheets, which uncovers significant amount of carbon. That carbon makes its way into the atmosphere, in amounts significant enough to warm the climate further.

    The Arctic permafrost feedback appears (to an outsider, like me) to be gaining widespread acceptance as a significant contributor to global warming both in the near term (the next century) and in the longer term (a few centuries.) Now we are trying to nail down the scale of the feedback. Meanwhile, we are starting to get some science that suggests a similar carbon-cycle feedback could unfold in the South, scale and speed unknown.

    Sunday, September 30, 2012

    Hoarders, Republican edition

    Given recent discussions of predilection for conspiracist ideation in climate deniers, I enjoyed the ad Redstate is offering me right now:

    Seriously:

    Apparently no one told them technology and the free market will grant us the magical power of instant adaptation to food shortages.

    The brain of a right-winger is a scary place these days. I don't know why. Tax rates are at a sixty-year low. Restrictions on abortion and barriers to family planning are multiplying like forest mushrooms after rain. We have a president who, except for his skin color, could easily pass for an Eisenhower Republican. Yet, in spite of all that, paranoia reigns.

    Maybe it's like the obesity epidemic. Fat, sugar, and leisure have always been an easy sell, because our genetic program responses powerfully to those inducements. Combined with wealth and modern marketing, the result is overconsumption and ill health.

    Similarly, the brain responds powerfully to fear. Politicians and propagandists (as well as the aforementioned marketers) have long understood this, and they sell fear like Nabisco sells cookies. It's nothing new. But perhaps the development of extensive electronic ecosystems dedicated to the far right have shifted this dynamic. Now for the first time, the audience can instantly respond to the material, enabling them to feed on one another's anger and fear.

    It's now painfully evident that most people subject to the relentless marketing of easy calories and labor-eliminating conveniences will consume them until they're sick with them, and beyond. Industries with no thought except to sell their hamburgers, cookies, PopTarts and sundry are contributing to a process that is killing off their customers. In ten or twenty years, we may look back on this unhealthy diet of fear the Right feeds its customers and recognize the same process unfolding; for recognition, power, and money they have sickened their customers by the excess consumption of fear, to their detriment and the detriment of our democracy.


    Friday, September 28, 2012

    Poll denialism


    Source

    People are starting to make some connections:
    One of the odder little subplots of the 2012 election has been the growth of poll denialism among Republicans. As Mitt Romney's chances have grown ever dimmer, a cottage industry has sprung up on the right claiming that presidential polls suffer from liberal bias and Romney is really doing better than they say. "When the published poll shows Obama ahead by, say, 48-45," explains conservative pundit Dick Morris, "he's really probably losing by 52-48!"

    Now, this is hardly in the same league as climate denialism or evolution denialism.
    Or vaccine denialism or rape denialism or . . . well, you get the idea. Here in America, one of our major parties has responded to the revolution in personal communication that began with 24 hour cable news and progressed to smartphones and the blogosphere by developing an independent, self-reinforcing, weather-dominator-scale doomsday device of cognitive dissonance.

    There is no unpleasant reality, the right has discovered, that cannot be shouted down by 128-bit quad-core sophistry. The latest fact to be dragged, gagged and bound, towards the conservative memory hole is Romney's dismal prospects in the upcoming elections:
    congressworksforus posted a comment in On Polls and Polling · 2 days ago
    I can guarantee you that the Romney campaign has access to far better polling than any polling organization that's posting public polls.
    The fact they are NOT changing course simply tells me that Erick is wrong, and that the public polls are horrible this time around.
    The fact that Obama has (if you pay attention) essentially given up on being re-elected (could he possibly make any more mistakes than he has the past couple of weeks) tells me that his campaign knows it is toast as well.
    Turnout will favor Republicans. The GOP built a ground game after 2008 that was effective (but not overwhelmingly) in 2010, but was *incredibly* effective a few months ago in Scott Walker's recall election (he got more votes than when we was first elected!)
    Believe me, Obama is not winning Ohio, nor is he winning Florida, and without either, he ain't winning. 
    Yep, we'll just take your word for it, anonymous Restate commenter. Poll denialism is rich with the sort of useful idiots who feel that good old horse sense and five minutes on WUWT qualifies them to dismiss radiative physics. Chait's take here
    This was the week that the political world discovered the burgeoning world of conservative polling denial. Just like other, better-established fields of conservative reality denial, the polling denial movement has its own levels of insanity. At the core sit the most fanatical of the denialists, like unskewedpolls.com, a popular site that offers its own twist on public opinion data, which currently has Mitt Romney leading Barack Obama by 7.8 percent nationally.
    The poll denialists’ argument holds that the polls — all of them, except Rasmussen, conducted by a right-wing pundit with a terrible record of accuracy — are over-sampling Democrats, finding nearly as many of them as showed up at the polls in 2008, which they consider a high-water mark for Democrats unlikely to be repeated. Pundits have patiently explained that polls do not make assumptions about the party identification of voters but merely report what voters tell them. And the most plausible explanation for the higher number of Democrats in polls is that increasing numbers of conservatives who reliably vote Republican are identifying themselves as independents to pollsters.
    So poll denialism is silly, and the conspiratorial explanation undergirding it is deranged.
    Steven Taylor is on the same page:
    I am astonished at the degree to which many who are rooting for Romney seem to be in total denial about the polling.  For example, the following from Katrina Trinko at NRO:
    But regardless of partisan breakdown, Republicans should be wary of taking any polls as completely accurate.
    “Part of the reason the Democrats won in 2008 was that when it looked as if McCain was going to lose, some Republicans stayed home,” argues McLaughlin. “So if President Obama is in a dead-even race with Mitt Romney in so many swing states, if the Democrats can convince enough Republicans they’re going to lose, it could take a one-point loss for the Democrats to a one-point win.”
    Emphasis mine.
    The thing that is remarkable about the above is that it not only in based in an approach that privileges preference over reality, it comes with a built-in fairy tale to explain any non-preferred results!  Using the logic above the polling can be wrong whilst predicting the actual outcome and, better yet, the wrong polling (that was actually right) wasn’t just wrong, but it caused the wrong outcome to occur!
    Life would be better for all of us if we were all, regardless of partisan preferences, a tad more grounded in empirics.
    Can I just say I wish the pundits and national media types would be as quick and forthright in confronting climate science denial? But of course, the difference is that most reporters don't understand climate science, while the concept of calling people up and asking them who they are going to vote for is a little easier to wrap your mind around. And again, as we saw with Todd Akin's comments, the immediate and obvious connection between the ideological worldview to the facts being denied helps people see deniers for what they are. The polls are brutally discouraging to my candidate = I deny the polls; the most scrupulous practitioner of journalistic false balance has got to be able to connect the dots on that one.



    Saturday, September 22, 2012

    Quantifying Lewandowsky madness

    A few weeks ago, a bright young man by the name of Stephan Lewandowsky came into the blogospheric eye because of a study which found a correlation between climate denial and the belief in other conspiracy theories.

    Now, possibly I have a warm spot in my heart for Dr Lewandowsky, having made much the same point on a number of occasions. But Lewandowsky didn't just spot the relationship, he demonstrated the association scientifically, in a tightly argued paper, now in press.

    Climate deniers were upset by this.

    The result has been Lewandowsky madness, a psychological disorder characterized by obsessive preoccupation with and demonization of a single, not-yet-published paper, whose crime was to provide evidence of something that anyone who has spent five minutes perusing their comment threads knows: a lot of deniers believe other silly things too.

    Climate Audit


    Total posts: 12 13

    Low point: Accused Lewandowsky of carrying out a “pogrom” after banning an abusive troll from his blog.

    (UPDATE): More Deception in the Lewandowsky Data

     

    Watts Up With That?

     

    Total posts: 15

    Low point: Confirms the scientific community’s impression of his chops by referring to Lewandowsky as  “Lewdandorky.”

    Steven Schneider’s 1992 argument against balance in science reporting

    The Blackboard

    Total posts: 9

    Low point: In “The Five Blogs” Lucia finds out her accusations of fraud and lying are totally unfounded after Lewandowsky gets permission from his university’s ethics committee to release the information that proves he’s tell the truth. Lucia decides he should apologize to her for making her wait.


    JoNova

    Total posts:  9

    Low point: N/A. Every word out of Jo Nova’s mouth is a new low for her and us.

    Bishop Hill

    Total Posts: 9

    Low point: In a massive failure of self-awareness, BH justifies his obsession: “The Lewandowsky story rumbles on, demonstrating an abilitity [sic] to generate new storylines that I'm sure few of us thought it ever could have.”


    A total of 56 57 blog posts about one not-yet-published social sciences paper.  So far, they’ve failed to identify a single serious problem with the study. Lewandowsky himself has a PhD in clinical psychology and a resume chocked full of well-regarded research. Yet Lewandowsky madness rages on.

    You might say, well, this isn't "madness," it's what the denialosphere does: they fixate on things. They fixated on the Hockey Stick, they fixated on Hansen's 1988 prediction. But this is very different. The Hockey Stick demonstrated and simultaneously provided an arresting visual image of global warming. Hansen correctly predicted the emergence of the global warming signal. This evidence is relentlessly attacked because it is important.

    Lewandowsky's paper, while interesting, and as far as I can tell well done, is not in the same league. If I were a denier -- which, not to be immodest, I would be great at, given my amateur knowledge of science and significant reserves of indignation -- I would address Lewandowsky's paper like this:
    "As you may know, there's a paper in publication that finds a correlation between climate skepticism and conspiracist ideation. It will be interesting to see if this holds up, but it does not surprise me. It's obvious by reading the comment threads at WUWT, Climate Audit, and elsewhere, that some of the people who are ready to challenge the IPCC narrative believe some really strange things. But this argument is about ideas and evidence, not people. Sometimes good arguments attract strange people. At the heart of the anti-slavery movement was an extremist religious sect whose members were radically pacifist, refused to swear oaths and shook like seizure victims in the middle of church services."

    Maybe it's easier for people already mistrustful of society over other issues to accept the fact that, as hard as it may be to believe, a small group of climate scientist and power-hungry government officials have sold us a bill of goods. Be that as it may, it's only a distraction from the discussion we need to have; a serious discussion, like adults, about the other side's best story, not about the fringe, not the endless and pointless argument about whose loons are more loony. This interesting paper should not tempt us into that pointless shouting match."
     But what do I know, eh? I actually believe we landed on the moon.