Monday, January 2, 2012

Five things I learned in 2011



1. Trees matter. A lot. They sequester more carbon than we thought; they generate cooling aerosols in their own right. We could do a lot to slow the advance of global warming if we decide to stop reducing forests in extent and start intensive reforestation.

2. The howls of outrage from deniers in the blogosphere in response to an argument vary in direct proportion to how effective that argument is with the broader public. There is a scientific consensus, and in many respects, the science is settled. The global is warming, and humans are the cause. Many deniers or "skeptics" get their funding from fossil fuel companies, exaggerate their qualifications, and misrepresent their results. This is simple stuff to those of us that live and breath this stuff, and deniers try to discourage us from making this arguments with howls of rage and jeering contempt. But they are not the people we need to convince, and the people we do need to convince -- the broader disengaged public -- these are powerful messages that should be underscored. Deniers know they are powerful, which is why they try and silence them.



3. Methane and CO2 release from the North (permafrost and methyl hydrates) could be apocalyptic in its effects. But the significance of this is undercut by the fact that the BAU pathway will almost certainly be apocalyptic in its effects. A lot of carbon is going to come out of those frozen deposits, but having studied it a fair bit this year, this quote from Raymond T. Pierrehumbert most closely reflects my own layperson's view:
But the clathrate release problem is in a rather different category from the runaway greenhouse issue. It has to be seen as just one of the many fast or slow carbon catastrophes possibly awaiting us, in a system we are just groping to understand. The models of destabilization are largely based on variants of diffusive heat transport, but the state of understanding of slope avalanches and other more exotic release mechanisms is rather poor — and even if it turns out that rapid methane degassing isn’t in the cards, you still do have to worry about those several trillion metric tons of near-surface carbon and how secure they are. It’s like worrying about the state of security of Soviet nuclear warheads, but where you have no idea what kind of terrorists there might be out there and what their capabilities are — and on what time scales they operate.
Or to put it another way: what would be the state of the climate today if this carbon didn't exist? Call that scenario one:
On a BAU pathway, we face mass extinctions, tremendous human suffering, and unpredictable feedbacks that could greatly accelerate climate change, including ice loss, glacier melt, forest fires, changes in ocean currents, and other known and unknown shifts in the climate and the biosphere.

With intensive mitigation, many of the same problems await us, but will hopefully develop more slowly, over several centuries, blunting the impact somewhat and giving us an opportunity to reverse some of the effects. We still have to worry about unpredictable feedbacks that could greatly accelerate climate change, including ice loss, glacier melt, forest fires, changes in ocean currents, and other known and unknown shifts in the climate and the biosphere, but forcing the system less intensely will, logically, reduce the risk.
Now add the carbon back in:

On a BAU pathway, we face mass extinctions, tremendous human suffering, and unpredictable feedbacks that could greatly accelerate climate change, including ice loss, glacier melt, forest fires, changes in ocean currents, release of methane and CO2 from permafrost and methyl hydrates, and other known and unknown shifts in the climate and the biosphere.


With intensive mitigation, many of the same problems await us, but will hopefully develop more slowly, over several centuries, blunting the impact somewhat and giving us an opportunity to reverse some of the effects. We still have to worry about unpredictable feedbacks that could greatly accelerate climate change, including ice loss, glacier melt, forest fires, changes in ocean currents, release of methane and CO2 from permafrost and methyl hydrates, and other known and unknown shifts in the climate and the biosphere, but forcing the system less intensely will, logically, reduce the risk.
In isolation, the potential for destabilization of this buried carbon would be a looming global catastrophe. But as it is, it becomes one aspect of a global catastrophe already in progress. That's how I see it, anyway.



4. Climate deniers represent a hard fringe of the American right; climate deniers in the blogosphere are an even smaller and more radicalized sub-group. Their views are not only more extreme than the large minority of the public that doubts the science of climate change, or the majority that is not ready to pay a significant price to combat climate change: they are fundamentally different in their outlook. You can see this in the opinion polls; you can see it in the comments and posts they make, in which a extreme anarcho-libertarianism features prominently. This ideology is totally unknown and would be bizarre to most American conservatives; to climate deniers it is practically conventional wisdom. Note also the amazing prevalence of what can only be described as the mentally ill, suffering from delusions that demonstrate grandiosity, paranoia, loose associations, and flight of ideas.

We can win the undecided middle to our side; there is evidence that this is already happening. We do it not by trying to win over or placate deniers, nor by trying to bait them. We win by telling the truth in a clear, simple, understandable way, by being less crazy and more normal, with the caveat that part of being normal is reacting strongly to people who attack hysterically and dishonestly.

5. Even as the overall picture continues to be grim, I found some of the research I came across this year comforting. This is turn reassures me that my filters, such as they are, are not the industrial-strength blast shields one often notes in one's opponents, but can easily overlook in oneself.

Although I remain very concerned about agriculture, I was happy to see that models that incorporated varying the type of crops and where they are sowed found a less severe impact from warming. Some crops will benefit from a CO2 fertilization effect.

Since warming over the last couple of decades has run at about 0.14-0.17C/decade, versus slightly more, 0.18-0.21C, as we would expect from the bulk of the models, the cheerful possibility exists that short-term climate sensitivity is a little lower than we thought, 2-3C instead of 3C-4C (possibly because the aerosol forcing is on the high side). So while the consequences of climate change, like glacier melt, continue to mostly run ahead of the models, it is hopeful that temperatures are running slightly behind. Of course, even a warming of 0.05C/decade or 0.10C/decade would be incredibly fast in geological terms and very dangerous. To see the danger we need only look at the response of the climate and the natural world. Still, better to be warming a little slower than we expected than a little faster.

-----------------------------

What did you learn in 2011?

4 comments:

  1. It makes me wonder if 'climate sensitivity is a misnomer. How about temperature sensitivity? Because if the planet is warming a little slower, then the climate is perhaps more sensitive to temperature than we thought, given observations?

    ReplyDelete
  2. Good point. There are a lot of complexities "climate sensitivity" doesn't reflect:

    1. How much biosphere carbon (CO2 and methane) will be unlocked by a given amount of warming? That doesn't change literal climate sensitivity, but alters the effective climate sensitivity -- total warming by ton of anthropogenic CO2 released.

    2. Is climate sensitivity fairly constant over all realistic temperature ranges, or is it different depending on the starting conditions? One would think, for example, that once all the ice is gone, climate sensitivity will be reduced, because that positive feedback will have run its course. If there are many such transition points, climate sensitivity might be quite variable.

    5. Short-term sensitivity versus equilibrium sensitivity. It's becoming clear that some of the slow feedbacks are not slow enough. What's the transient sensitivity at 20, 40, 80, 150, 250 years? The exact shape of that curve could prove vitally important.

    4. As you point out, what is the climate actually gonna do in response? I would think that everyone would grasp that this is the great unknown, but not so. I'm reading Richter's book, "Beyond Smoke and Mirrors," and so far it's very good; he's a bright guy who knows AGW is real and that we have to act. But he falls into that very common trap of focusing on temperature uncertainty to the exclusion of other kinds of uncertainty -- he describes the BAU pathway as uncertain between +2C ("disruptive") to +6.5C ("disaster.")

    Whereas we don't know what another +2C will look like, and the indications from +0.8C from preindustrial are not reassuring. So you really have to take into account both kinds of uncertainty and describe BAU as ranging from +2C (disruptive to disaster) to +6.5C (disaster to apocalypse.) And if "disaster" comes up more than once in that this of possibilities, there may be a good reason for that.

    ReplyDelete
  3. My Tweet's "&<2#2" expanded: And [there is] more to [be learned regarding] #2. Had I had the characters to spare, I would have included #4 too.

    To my ear, the logic driving your arguments and assumptions—and seems to inform what you have/can learn—is distinctively liberal in its moral construct. I think a more inclusive view will demonstrate that to "convince" the unconvinced, liberals will need to give up feeling moral by simply being right, rather than doing right. For people elsewhere on the liberal/conservative moral continuum, to be heard as being moral ones living needs to give life to what the professed knowledge demands relative to integrity. Only those on the liberal pole of the continuum, and relative to AGW issues, seem to avoid such maturity/integrity while feeling moral. I observe that doing morality this way helps us avoid having to deal with root—and unconscious—causes (economic/religious/our meme's iteration of motivated reasoning).

    It seems to me that during my lifetime this being-right-not-doing-right dynamic has made liberals a joke to everyone—but themselves. Among blue collar workers there is a truism: "those who can't do, teach." which captures what I mean. At least I have found such a view to be helpful for seeing what needs to be done differently than what you appear to have learned to be worthwhile endeavors.

    In addition, #3 is also a big thing for me (in terms of what I learned/had confirmed). #5 withstanding, since the science closed on the 2007 IPCCC report in 2005, all the trends in science have pointed to grave and compounding errors in the "trusted" assumptions the climate modeling is predicated on. I feel we are at a time—and due to a lack of integrity in how we live commensurately different relative to a professed knowledge—where what is not known relegates the information that is scientifically grounded in what is known is so conservative so as to be next to worthless . . . unless being "right", relative to "deniers" is all one is seeking to feel! ;)

    BigWhoopie!

    ReplyDelete
  4. nice Thanks for sharing this valuable information with us
    ac duct cleaning Hacienda Village fl

    ReplyDelete