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Last Build Date: Fri, 16 Feb 2018 22:29:38 +0000


Comment on The global CO2 rise: the facts, Exxon and the favorite denial tricks by CCHolley

Fri, 16 Feb 2018 22:29:38 +0000

Mike @176
Not that I want to get into the weeds with natural paleo warming rates but there exists a maximum natural warming rate at or below for which no one should have any objection.
Not really, the paleo has never shown warming at the rate we are currently experiencing. Not even close. It is unprecedented. The PETM took thousands of years. You could argue the paleo isn't refined enough for the current period, but there is nothing to suggest that the current warming will not continue at its current rate as long as we continue to emit. The rate of warming is already causing ecological issues. Species will not be able to adapt fast enough.
Per the above, if we warm slowly, what’s the “mess of trouble”? Life did quite nicely when earth was a lot warmer. (Wasn’t the Sahara once a big swamp ‘only’ 100KYA?) At least can you admit avoiding another plunge into an ice age would be a big plus? Does someone actually know what global temperature would be “best”?
Being that you are the one who is concerned with the consequences of making bad assumptions, you should consider that it might be you who is making bad assumptions. There is no possibility of a low climate sensitivity and slow warming. We are already warming too fast. We've already taken care of the next ice age so that is not a consideration. Yes, the planet has been warmer in the past, but not during civilization. For civilization the best planetary temperature is a stable temperature. Of course overall there is no *best* temperature, but if we continue at some point it will be too warm in the lower latitudes for any kind of existence. Not to mention that there is no fertile soil at higher latitudes where the climate will be temperate enough to grow cereal grains. And what about sea level rise? How much is acceptable to you? Last time the atmosphere was at 400 ppm of CO2 sea levels were somewhere in the neighborhood of 85 feet higher than today. Does that sound acceptable to you? With thermal inertia those kinds of sea level rises are already in the bank. I'll repeat it again, yes there is uncertainty in ECS, but no uncertainty that it is high enough to be problematic. None. Your assumption is wrong. And finally, it is quite possible your economic cost of mitigation assumptions are wrong. REMI study on a revenue neutral carbon fee and dividend plan say it would actually be an economic stimulus. The risk is high, the consequences dire, and the cost to mitigate reasonable. Any competent engineer who has properly vetted all the relevant information would easily make the right call on this one.

Comment on Unforced variations: Feb 2018 by nigelj

Fri, 16 Feb 2018 22:13:30 +0000

MA Rodger says 7:20 – It isn’t that the climate is more sensitive to GHGs than was thought. It is the climate is more sensitive to the ‘warming’ resulting from the GHGs. Thus the concern with 1.5ºC. Killian responds. This is pedantic. The colloquial meaning is exactly as stated. You are making corrections important to scientists, not laypersons who know little of the science. Its not pedantic. We can get lulled into a false sense of security with talk that climate sensitivity might be low or medium (and right now we still don't know for sure where it is, other than to say the majority of evidence points to medium). What is entirely possible is the weather itself and rates of ice collapse could be much more sensitive to even small changes in temperature, so low or medium climate sensitivity, than we thought. Looking at data and the preponderance of very bad weather the last couple of years makes me think this may be the case although I admit some of it is anecdotal. But I understand sea level rise right now is actually towards the upper end of estimates so this suggests either climate sensitivity is towards the high end, or ice sheets are very sensitive to low or medium climate sensitivity. Is there research on this sort of way the weather is responding to temperature? Is it more or less than expected? And this is fundamentally a science website! It talks about what is of interest to scientists and global warming nerds etc. It tries to simplify issues for the public, but this is only part of its purpose.

Comment on Unforced variations: Feb 2018 by nigelj

Fri, 16 Feb 2018 21:50:45 +0000

Killian @106 and other posts. For gods sake man, calm down. Mike just looked at your post where you didn't like the term 'intersecetionality' and suggested a link on the content of the idea. He couldn't really know what you know or don't know on the issue. He was trying to be helpful. He wasn't implying you are an ignoramus. You also seem singularly incapable of understanding what people post, even when its clear. Read - more - slowly. Fwiw I also find the term intersectionalilty annoying, like business speak and I deliberately try to avoid jargon like this, if it can be said in other ways. The interrelationship of things should be self evident. On the other hand, maybe it isn't to some people. And I like some of the organisations you are part of especially anti racist groups etc and groups that bring together a number of issues.

Comment on IPCC Communication handbook by Ray Menard

Fri, 16 Feb 2018 21:24:57 +0000

Think it's an excellent guide. I think we often forget to engage about things people care about, particularly failing to connect with those that live in rural areas, where at least in the US there's huge and disproportionate politic power to change things. If I talk to a buddy on the East coast, I sometimes start talks about climate change by remembering a great time we had searching for trout in the mountains; on the West coast about the great times we used to have eating raw oysters off the beaches--things our children will never get the chance to experience.

Comment on Forced Responses: Jan 2018 by Mr. Know It All

Fri, 16 Feb 2018 21:07:01 +0000

385 - Killian ".......According to the USDA’s latest data, by 2010-11, no-till farming had grown to the point where roughly 40 percent of the corn, soybean, wheat, and cotton grown per year in the U.S. used either no-till or a half-step technique called strip-tilling. That works out to around 89 million acres per year." How much did these agricultural practices reduce the concentration of CO2 in the atmosphere? Did the actual, measured, reduction agree with the calculated reduction? If not, why not?

Comment on The global CO2 rise: the facts, Exxon and the favorite denial tricks by CCHolley

Fri, 16 Feb 2018 19:22:12 +0000

Mike @175
Exactly nowhere did I state “therefore no problem” thus making that conditional aspect of your criticism thoroughly specious.
No you didn’t, but you did state that selecting an average ECS for a basis of decision making is “fools gold from an engineering standpoint” which may well be true, but the premise is false—we do not use an average, we use a probabilistic range. Other than the “fools gold” statement, you did not make a point, but then what is your point if not to imply there is not enough information to make a decision? Claiming there may not be a problem; therefore, do nothing, is almost the same as claiming there is no problem.
There are consequences to making decisions based on incorrect assumptions, often bad ones. I assert that with AGW there is no such option to “design for the worst case” because doing that could conceivably cause more harm than if nothing was done at all. If you believe that there would be little difference in the global economic impact in having to mitigate for an ECS of say 4.0 versus 0.5 then perhaps you are a fool?
I am well aware of risk mitigation relative to design decisions as that was a large part of my responsibilities over much of my career. A rather successful career I might add. The resources or costs spent in mitigating a risk is dependent on how we view the odds of a negative event occurring, the strength of our assumptions and/or knowledge, and on how bad the consequences of a negative outcome will be. A relatively low risk outcome that will result in a catastrophe can demand significant investment in mitigation. As for AGW, of course the economic impact responding to an ECS of 4.0 versus 0.5 would be different. However, mostly in the time value of money because even a relatively low ECS would have dire consequences, it would just take a little bit longer, but not so much longer as to not wreck havoc for future generations. Sea levels are already rising and accelerating fast enough to have huge economic impacts. But your point is moot anyway because the low end possible ECS is physically constrained as I explained before. The likelihood of an ECS of 0.5 is so small as to not even be possible. Even the lowest ECS within the realm of probability is still too high. Per IPPC: Based on the combined evidence from observed climate change including the observed 20th century warming, climate models, feedback analysis and paleoclimate, ECS is likely in the range 1.5°C to 4.5°C with high confidence. I believe the low end of 1.5 has been since discredited. It was based on observational analysis which was found to contain errors. Most likely low end is probably back to 2.0 degrees per previous estimates.
I’m unaware of a paleo record confirming an ECS of 3 degrees. I’d like to see a best example of that to learn how it was done.
Paleo confirms 3 degrees most likely. Review IPPC report. Also see:

Comment on The global CO2 rise: the facts, Exxon and the favorite denial tricks by Mal Adapted

Fri, 16 Feb 2018 16:54:48 +0000

I think sometimes that people use D-K diagnosis as a way to hide their own “denial” about human psychology and human behavior. It describes a narrow effect; it doesn’t really explain much.
Uhh. You may be confused by my use of 'diagnostic'; I intend it to denote "characteristic of a particular species, genus, or phenomenon", namely the pattern of self-deception evident in Peter Carlson's comments. For the psychological definition of 'denial', I'm relying on that unimpeachable source Wikipedia 8^D! I'm not a psychological professional, so I'm not attempting to explain the origin of Mr. Carson's stubborn rejection of the overwhelming evidence for AGW, nor his clearly mistaken belief that he's competent to contradict the consensus of working climate scientists. As I've said here and elsewhere, the descriptive terms 'DK-afflicted' and 'AGW-denier' may be applied without needing to explain why someone would persistently reassert unsupported nonsense with such unshakable confidence, nor why they're so uncomfortable with a redundantly-verified fact. Kruger and Dunning 1999 described a similar pattern the authors observed in their test subjects in controlled experiments. They likened it to medical anosognosia, but didn't try to trace its neuro-psychological foundations. Bear in mind they were awarded an Ig Nobel Prize for it, having gotten their names attached in the popular imagination to a phenomenon that, once recognized in oneself, is painfully obvious in others 8^}. FWIW, my own 'ouch' moment came in 2008, when I first encountered the phrase "Dunning-Kruger effect" on the Internutz. I immediately ceased commenting on blogs when I couldn't identify genuine experts on the topic, and I've made no claim to be an expert about any scholarly discipline since. Like AGW, f'rinstance: all I know about it is what's in AR5 (and Weart's The Discovery of Global Warming, etc), yet it's apparent to me that Mr. Carson knows even less! I think both 'DK-afflicted' and 'AGW-denier' fit him pretty well, but YMMV.

Comment on The global CO2 rise: the facts, Exxon and the favorite denial tricks by zebra

Fri, 16 Feb 2018 16:44:07 +0000

Eli Rabett #179, I may well be wrong on this, but did you mean to say: "What determines the rate at which a particular wavelength escapes to space..." ? I get confused by the way people use "level" and "height" on this issue. I have always imagined it as a "band" rather than a two-dimensional surface-- where radiation emitted by a molecule at the bottom of the band is captured, or not, by the molecules above it. The "height" would be the surface that defines the bottom of the band, correct?

Comment on The global CO2 rise: the facts, Exxon and the favorite denial tricks by Hank Roberts

Fri, 16 Feb 2018 16:43:33 +0000

Victor Gostin, Associate Professor (retired), University of Adelaide, Australia signed this letter:
Some issues are of such ethical magnitude that being on the correct side of history becomes a signifier of moral character for generations to come. Global warming is such an issue....

Comment on The global CO2 rise: the facts, Exxon and the favorite denial tricks by Kevin McKinney

Fri, 16 Feb 2018 15:40:03 +0000

"At least can you admit avoiding another plunge into an ice age would be a big plus?" Sure--although 'big' may be misleading, I think 'plus' is fair. Guy Callendar made the same point in his 1938 paper on AGW: However, that 'comfort' is vaguely analogous to a 50-year old getting a heart transplant from a 20-year old: in order to receive the the possible longevity benefit of the youthful heart, the recipient must first survive decades of a suppressed immune system function (not to mention the health and financial costs of massive surgical trauma.) And that understates the differential; in the case of humanity, we have a potentially existential threat, starting essentially *now* and extending for tens of millennia, in exchange for putting off a much slower-acting threat tens of millennia (or more) distant. (And one we already survived, actually, albeit not as agriculturists--let alone technologists in the modern sense.)