It is time to stop quivering in our boots in pointless fear of the future and just roll up our sleeves and build it.
- Ray Pierrehumbert

Monday, April 4, 2011

The Devil His Due

There's something to be said for appreciating what your usual opponents say that is good and worthwhile.

I'm a long way from an unalloyed admirer of Roger Pielke Jr., but once in a while, too often for pure randomness, he hits a nail on the head. And he has two pieces right now that I'd put in that category and then some. I think they are important and shouldn't be missed. The more recent one is about the innumeracy of a proposed carbon neutrality solution in Australia. (This is the Dyson solution, isn't it?) Quoth Roger:
It is easy enough to check the video of the interview to see what Hunt actually said (starting at 9:30) and to realize that the transcript on his official web site is falsified.
which is strong language, and happens to be true.

But even more interesting is his piece on the obsession with global mean surface temperature, which I think is compelling. GMST is not the problem. Carbon is the cause, local climate disruption is the impact. If GMST goes up a lot, the impacts cannot be small, but if GMST does not go up a lot, the impacts may still be large. Roger Jr. explains succinctly. He avoids getting too deep into his father Roger Sr.'s peculiar understanding of the physics, with which many of us take issue, and simply makes the point that huge climate changes are possible with zero temperature change in the global mean. A point often lost in the shuffle by the stickerati, (including to some extent Mann, Briffa, Jones, McIntyre, Watts, Liljegren, Hausfather, Barnes, Christy, Spencer, and now Muller) who to various degrees and various extents seem to think that climate science somehow boils down to a single time series, and stands or falls on the accuracy thereof.

This is what Roger Jr says about it. Though a bit understated for my taste, it is substantively exactly right in my opinion:
In the real world, the effects of increasing carbon dioxide on human and ecological scales are well established, and they include a biogechemical effect on land ecosystems with subsequent effects on water and climate, as well as changes to the chemistry of the oceans. Is it possible that these effects are benign? Sure. Is it also possible that these effects have some negatives? Sure. These two factors alone would be sufficient for one to begin to ask questions about the worth of decarbonizing the global energy system. But greenhouse gas emissions also have a radiative effect that, in the real world, is thought to be a net warming, all else equal and over a global scale. However, if this effect were to be a net cooling, or even, no net effect at the global scale, it would not change my views about a need to consider decarbonizing the energy system one bit. There is an effect -- or effects to be more accurate -- and these effects could be negative.

Of course, not mentioned yet is that action to improve adaptation to climate doesn't depend at all on a human influence on the climate system, warming or cooling or whatever. Adaptation makes good sense regardless. So clearly my policy views on adaptation are largely insensitive to any issues related to global average temperature change.


The debate over climate change has many people on both sides of the issue wrapped up in discussing global average temperature trends. I understand this as it is an icon with great political symbolism. It has proved a convenient political battleground, but the reality is that it should matter little to the policy case for decarbonization. What matters is that there is a human effect on the climate system and it could be negative with respect to things people care about. That is enough to begin asking whether we want to think about accelerating decarbonization of the global economy.


To fully assess whether accelerated decarbonization makes sense would require us to ask, are there any other good reasons why accelerated decarbonization might make sense? And it turns out, there are many.
Yep.

In the end the GMST time series is almost purely a distraction. If we have that right or wrong matters far less than it's made out to. The other 9o% of the WG I reports are far more compelling, if a little harder to understand. That's why I think the whole matter reduces to empty gossip.

Update: Nick Barnes (along with a CCF colleague) comments below on his inclusion in my list of the GMST-obsessed in an interesting way. Yes, this is the beginning of my response to Dan Olner: it is a useful communication tool, and his broad understanding is correct. But in a sense it does not HAVE TO BE correct; the step that goes from heat to temperature is far more complicated in detail than the simple explanation allows. This is the point that Lindzen and Spencer stubbornly adhere to. It seems clear that they are wrong, but they can't be refuted at the level of Dan's model.

It's hard to come up with a scenario where the sensitivity is negative, but it's not that hard to come up with one where it is very small. My point, and Roger Jr's point, is that even if true, even if the sensitivity is small, that doesn't suffice to argue that anthropogenic disruption of climate is not worth worrying about.

31 comments:

Steve Easterbrook said...

His terminology is a little unhelpful. It took me a while to figure out that when he says "...and these effects could be negative" he doesn't mean 'negative', he means 'really bad'.

I've also long puzzled over the obsession with surface temperatures. Is it because most of the rest of the physics is far to hard for the ignoranti to understand?

King of the Road said...

Perhaps it's because the code phrase for contemplation is and has been, for a couple of decades, "global warming." So, if you want to make the case that there's nothing to worry about with respect to ... global warming... then what could be better than to show that "here is the globe and here is its temperature and, as you see there's (no, little, insignificant, no statistically significant - choose one) global warming.

Michael Tobis said...

That's definitely part of it.

Global warming as an alias for climate disruption one minute, global warming in the literal sense the next.

It's a shell game. Nothing is better than retiring to a Caribbean island with your beloved while you are still young and healthy. A peanut butter sandwich is better than nothing. So a peanut butter sandwich is better than the Caribbean island thing, right?

If a word has two meanings in a conversation, it presents an opportunity to confuse.

Brian said...

GMST is a decent single number to use. Feel free to come up with a substitute.

Re Roger Jr., he's been on an upward trend in helpfulness, maybe blasting through the helpful 5% of the time level. Haven't checked on him in a little while though.

for4zim said...

This is a straw man. No scientist is reducing climate change just to a change of the surface temperature. There are many parameters observed and discussed like change of glaciers and ice caps, change of biodiversity and ecological systems, change of hydrological cycles and wind and...

On the other hand, the starting point of most climatic changes is the change of the radiation budget which leads in the first place to an accumulation of heat and therefore can be best observed by measuring temperatures (of course not just surface temperatures). Therefore, on the one hand you can't reduce climate change to a change of the global surface temperature, on the other hand it is a very important metric and not insignificant at all. (Of course the changes to our climate don't stop there. And of course, in addition there is the reduction of pH with a string of effects attached to it.)

Just because Wattsupwiththat and like campaigners made the global surface temperature a holy grail doesn't mean any respectable scientist has ever reduced global change to just this. That is the reason this sounds like a straw man to me, perhaps as a preparation to leave a denier point which is no longer effective. We know, that new points will be used then. Like, global change is so complicated that we can't possibly say whether its impact will be more negative than positive. Because there is so much more to it than just somewhat rising global surface temperatures, which are not interesting to "us" any more.

Dan Olner said...

"Sorry, we were unable to complete your request." I just lost my entire comment. Note to self: never write comments in blogger's own comment box. GRAAAAARRRR.

Dan Olner said...

I'm not a scientist, so maybe I've missed something here, but I agree with for4zim: "the starting point of most climatic changes is the change of the radiation budget which leads in the first place to an accumulation of heat and therefore can be best observed by measuring temperatures."

Jr says: "Adaptation makes good sense regardless. So clearly my policy views on adaptation are largely insensitive to any issues related to global average temperature change." That makes absolutely no sense to me - unless he's talking about adaptation to something else. But then, why is he talking about mean global temperature and not the nitrogen cycle, or whatever it was he was thinking about? If he's talking about adaptation to climate disruption -

When we're discussing mean temps, they dictate the climate disruption caused by the energy budget re-equilibriating due to the carbon we put in the air...? We can agree that the mean temperature isn't the point (and neither would distance to the oncoming asteroid be the point!), but isn't it the basis for bracketing expected disruption outcomes? If the mean is lower than expected in a given scenario, the expected impacts will be less than thought, and vice versa. Yes? And thus the best starting point for building adaptation strategies? I cannot for the life of me see how you disconnect the two.

Are non-ocean temp means just not a good measure for changes to the energy budget?

Arthur said...

Pielke Jr. makes an even deeper positive impression here: Global Warming: It's Worse Than You Think - with the interesting comment:

"About ten years ago, back in my “denier” days, ... But ... the big problem - sea surface temperatures - continues to be ignored. There are in fact good reasons to believe that existing SST series understate sea surface warming since 1940 by 0.3-0.4C, which if so would indeed make global warming look a lot worse ..."

He's still a weasel (see statement that follows the above). But a surprisingly reformed one, now.

By the way, coincidentally with MT's post here that agreed that GMST is not important, Bob Grumbine and I happened to both post predictions for GMST for 2011 (and I also threw in 2012 and 2013):

Starting to work with data - Grumbine

Predicting future temperatures - Me.

Bob's post doesn't factor the current (fading) La Nina yet into his number (he doesn't call it a "serious" prediction), so he's got bigger error bars: 0.6216 plus or minus 0.098 (NCDC scale). My estimate for 2011 is 0.58 plus or minus 0.05 (GISS scale, which is pretty close to NCDC, using the same baseline).

Bob does point out the naive "no trend" estimate would be 0.0086 plus or minus 0.252 - I suspect we're all willing to bet that prediction would be wrong :)

Michael Tobis said...

Global sensitivity is a convenient number for many purposes, and finding out its true value is a worthwhile endeavor. The instantaneous trajectory is perhaps less so, but it's obviously relevant to the sensitivity.

But it is meaningless to use it to "disprove global warming theory" the way so many do. And some scientists do tend to fall into the trap of using it, in turn, to defend "global warming theory".

RPJr's point is one I agree with. Even if the global sensitivity were zero, unlikely though that is, that would not actually mean that anthropogenic CO2 forcing was not dangerous. It is impossible to have a large change in GMST without a large climate change, but on the other hand, it is quite possible to have a large climate change without a large change in GMST.

Analogously, we sometimes say a person is dying of "a fever", and indeed in extreme cases that is possible. More often, though, the fever is an indicator of other disruptions in health. It is possible to be very sick without running a fever, too.

A high fever is a clear sign of illness, but if a person is very ill you don't boot them out of the hospital because their temperature is near normal.

And if someone is eating some cumulative poison, you don't tell them it's okay to keep ingesting the poison because their fever is a bit lower than you expected, especially if there are other reasons to suspect they may be getting sick.

The point is not to ignore GMST; it is a useful measure. The point is to stop fetishizing it. "Global warming" doesn't mean we are at risk of a few of degrees of warming. It means we are at risk of massive climate change that comes along with it.

How massive? Well, that depends on many things, not just GMST.

Dan Olner said...

MT: "It is impossible to have a large change in GMST without a large climate change, but on the other hand, it is quite possible to have a large climate change without a large change in GMST."

Is it possible to have a large *co2-forced* climate change without a large change in GMST? If so, I'm completely misunderstanding something fundamental here! My understanding was: Co2-forcing = extra energy = more heat in the system. Most goes to the oceans; some must show up in surface and atmos temps. I can picture a situation where the mean stays where it is but regions destabilise. But how is it possible for the mean to remain fixed when you're increasing the overall energy input? Or are we talking about feedbacks that we don't understand fully yet? (Notwithstanding Daisyworld-like self-regulation, I presume we're not talking about that...)

"But it is meaningless to use it to 'disprove global warming theory' the way so many do." If global mean temperature doesn't increase in a statistically significant way on a climate-related timescale, it would disprove it, wouldn't it? I mean, given the timescale involved, it'd be too late either way - we have to run the experiment - but in theory, it still would. Obviously, deniers bringing up Popper to say `the theory isn't falsifiable' is nonsense, since there are so many other lines of evidence. Perhaps you mean the way any yearly dip is used to megaphone "climate change has stopped!", in the same way any flurry of snow is used...?

for4zim said...

Arthur, the comment you assigned to Roger Pielke jr. ist from another, unrelated Roger.

EliRabett said...

Adaptation without mitigation has huge procrastination penalties. Which, in simple words means that it is futile because you can't get ahead of the trend, nor, even if we could, could we afford to.

ijish said...

Oh duh. A stopped clock may be exactly right twice a day, but I don't feel compelled to praise a stopped clock to the high heavens every 12 hours.

This is getting to the point where I actually start wondering if MT really means what he writes, or if he's writing certain things just to please certain people. That can't be good.

-- frank

manuel "moe" g said...

MT, I know this is not your intention because your sincerity is beyond reproach...

... but your last two posts demonstrate Shaolin Master levels of the jujitsu of the backhanded compliment and the kung-fu of "damning with faint praise". ;-)

[My own snottiness aside...] Not only does MT bridge the gap with the other side of this argument, but he gets profound results from the effort. Cheers!

Steve Bloom said...

Dan, I use the box but have learned to *always* copy the comment so that if it's eaten I can just paste it in and post again.

Steve Bloom said...

It's a little peculiar to accuse Mike of that sort of confusion.

Also, did you notice that the analysis you so glowingly commend resorted to unphysical reasoning? (Of course you did, but you were on a mission to find something nice to say.)

In particular, if there really were zero temp change in GMST there could still be major climate impacts? What an odd idea (albeit dependent on how one defines "major"). It's certainly true that advances in the science in the last few years, mainly on the paleo front, have shown that relatively small increases in CO2 and thus GMST *will* have big impacts (with no uncertainty whatsoever, the big questions being about timing and spatial distribution), but that's a quite different statement. Even if one defines climate events like the southwestern U.S. medieval megadrought(s) to be major, the likely culprit was the slight increase in GMST associated with the MCA, the obvious takeaway point being that precipitation patterns are extremely sensitive to very small changes in GMST. Are there counter-examples?

Michael, sometimes when you write things like this I think you must spend as much time with therapists as with climate scientists. Oh wait...

Anyway, by all means don't attack RP Jr. unless provoked, but do ignore him (and Kloor). The degree of provocation it took for you to finally come to that conclusion re Fuller was something to behold, and unfortunately it seems that you're uninterested in applying the lesson elsewhere.

seamus said...

"The way to live is to live as if you already lived in a civilized society"

This means I will now live as if the "debate" over AGW is over. It truly has been over for quite some time now, and settled enough to move on. Dwelling on, for example, adaptation vs mitigation is a stalling tactic. Framing, semantics, vested interests, doubt merchants: entanglements.

Climate change question and answer period is over. Dangerous climate disruption will happen if every effort is not made to de-carbonize.

Ah, there we go. Climate science can be left alone to continue doing it's thing... the debate is now about implementing a clean energy economy. And that's what it's really been about all along.

Adam said...

Anyway, by all means don't attack RP Jr. unless provoked, but do ignore him (and Kloor). The degree of provocation it took for you to finally come to that conclusion re Fuller was something to behold, and unfortunately it seems that you're uninterested in applying the lesson elsewhere.

Well spoke.

There is no accommodation possible with P and K that does not involve some degree of ignominious submission, MT. That way lies Curry-dom.

I appreciate your yearning for peace with climate warriors of evident intelligence, but when such creatures are deficient in intellectual integrity, peace can only be bought by becoming one of them (as Dame Judith has found, perhaps at last to her sorrow).

NewYork said...

RPJ: There are in fact good reasons to believe that existing SST series understate sea surface warming since 1940 by 0.3-0.4C

Hold on now...where does RPJ get that from? I'm aware of the Thompson 2008 study and also of the ship -> buoy measurement change. The latter I think is constrained to increasing the SST trend by just a few hundredths over the last decade, while I thought the corrections to the early 1940's issue will have little effect on the long-term trend. Anyone know what RPJ is referring to?

David B. Benson said...

NewYork --- His own state of confusion, I'm sure.

Michael Tobis said...

NY, David, - I was wondering that too; I figure it is some garbled Roger Seniorism.

I haven't quite put my finger on Roger Junior's Super Power, but his Vulnerability is definitely Roger Senior.

Arthur said...

for4zim - thanks for the correction, it sounded a bit like RPJr, but he clarified later in the thread that it was not him. Still the main body of the post (on land temperatures) by RPJr was somewhat reasonable.

I.e. - NewYork and later - that quote was from some other Roger, not Pielke Jr.

I've been thinking a bit more about Michael's main point of agreement here, and I think there's a subtlety that needs to be addressed.

The climate change we're concerned about results from a radiative imbalance: more energy absorbed by the planet than is leaving. This is Dan Olner's point as well, I think.

That is, as long as there is a radiative imbalance, we are continuing to accumulate energy in the climate system. And the only ways to restore balance are to either decrease incoming absorption (through albedo changes, say - but I'm not aware of any such feedbacks expected in this case, except perhaps by Roy Spencer and Richard Lindzen) or to increase outgoing emission to space.

And the only way to increase outgoing emission (for given atmospheric profile/composition etc.) is to increase the temperature of the radiating regions.

And that increase in temperature to restore radiative balance almost certainly requires an increase in global mean surface temperature along with it.

That is, the increase in GMST is required to return to a dynamic equilibrium state where we are no longer accumulating energy.

A non-increase in GMST under net energy absorption by the planet can be only a temporary condition, and the longer it lasts, the *greater* the effects of the warming once we do restore balance, because it involves that much more energy in the system. It means more "warming in the pipeline" for any given change, and more opportunity for larger, longer-term feedbacks to come into play.

Nick Barnes said...

Whether or not "Barnes" is me, I'd just like to say that I broadly agree with this: GMST is not a great figure-of-merit.

However, there are good communication reasons to have a single figure-of-merit, and I don't think there is a better one than GMST for communicating to the public. For the science, a better single figure might be net anthropogenic radiative forcing, but that number is effectively impossible to measure, so it strengthens the rhetorical case of the nihilists who say "everything which depends on models is wrong". Net forcing is also hard to explain to the public.

GMST is relatively easy to explain, easy to understand, and is based in a pretty straight-forward way on familiar measurements (i.e. thermometers). Those are its strengths. I readily concede the weaknesses you present.

drj11 said...

I should add to Nick Barnes' comments (with which I broadly agree), that our efforts so far (in ccc-gistemp and Climate Code Foundation) have not been to promote GMST as a figure of merit. The figure of rising temperatures has already achieved prominence in the public debate (and some of the promotion to get it there has been done by perfectly respectable scientists). Our efforts have been focussed on removing the mystery surrounding how such figures are produced. In that regard, I think we have had some success. (and I think Hausfather has been important in that too, but I can't speak for him).

for4zim said...

Arthur – it is brilliant to think the problem from the end. Indeed, restoring the radiation balance forces a change of GMST.

But I would even dig further. The reason why I see the opinion of Pielke jr just as a next step in the denier dance is:

a) Straw man: global temperature is not a holy grale, it is exactly one parameter of many which gives us essential information. If the GMST in statistical significant periods would leave the bounds given by the models (by the theory) the theory would be wrong. If the global temperature would not rise in the expected way I would doubt the theory. The global change theory is falsifiable. Pielke jr want to treat the one parameter as insignificant with which global climate change can be shown to be consequential. It is somehow not a surprise that this comes at a time after shouting „hoax“ at GISS and CRU wears out, investigations found no wrong doing and BEST will yet again come to the same conclusions.
b) Rising temperature is not just rising temperature. It means:
higher evaporation, therefore drought where it doesn't rain more and floods where it rains more
more weather extremes, more heat waves
if the global temperature rises a lot (8 or 10 degrees), it might create areas, where human beings (and many animals) can't live outdoors any more
rising sea level
in some areas some kind of seeds will no longer grow in spring because they need a freezing period to be activated
less oxygen solved in water, more areas of oxygen free dead zones
So, if the global temperature would not rise global change would be much less of a scare for me (neglecting pH-decrease at this point). What else should drive effects of global change, if the radiation imbalance would not in the beginning change temperatures? Just a redistributiuon of heat without net change as Pielke jr proposes? That is highly implausible.
c) Doing a Judith Curry or pretending ignorance where we have actual knowledge: climate sensitivity is between 2 and 4.5 degrees Celsius on a 90% significance level at least. Why should we even consider a sensitivity below 1.5, when it would make it hardly possible to explain climate change at any time in the past and present? We are not ignorant, therefore we can say a lot about likely trouble from climate change, therefore we know why decarbonation is neccessary.

Steve Bloom said...

MT: "(I)t's not that hard to come up with one where it is very small."

Huh? Only if you completely ignore paleo or alternatively assert that very low sensitivity results in big changes, neither of which Lindzen and Spencer seem to care for. It may be intellectually interesting to see if you can derive sensitivity based on atmo science alone, but please watch it with standalone statements like the one above.

Steve Bloom said...

Arthur: "That is, as long as there is a radiative imbalance, we are continuing to accumulate energy in the climate system. And the only ways to restore balance are to either decrease incoming absorption (through albedo changes, say - but I'm not aware of any such feedbacks expected in this case, except perhaps by Roy Spencer and Richard Lindzen) or to increase outgoing emission to space.

"And the only way to increase outgoing emission (for given atmospheric profile/composition etc.) is to increase the temperature of the radiating regions."

The difficulty I have with this is the implied chronology. Is there some way in which the radiative imbalance can be de-linked from the T increase? IOW, while the equilibrium T increase indeed lags, the adjustment begins instantaneously.

Michael Tobis said...

"Huh? Only if you completely ignore paleo or alternatively assert that very low sensitivity results in big changes, neither of which Lindzen and Spencer seem to care for."

Agreed. I'm pretty convinced that the Charney sensitivity is in the neighborhood of 2.5 C - 3.0 C . I'm not suggesting otherwise.

Neither am I suggesting that this quantity is scientifically unimportant. It is important as a global index for several reasons, including that the paleo record gives us some handles on it.

I am only saying that it is far less important from a policy point of view than is generally made out. Specifically, while there are no high-sensitivity low-impact scenarions, there are low-sensitivity high-impact scenarios.

By virtue of calling our problem "global warming" rather than "climate disruption" we reduce to a single number a set of difficulties that is far more complicated than that, plus we set up circumstances where a political confrontation easily emerges as a proxy for a reasoned and informed discourse.

To determine how deep in the hole we already are or are going to get, GMST is not the key. Severe events, interannual variability, shifting rainfall zones, ice cap melting, carbon feedbacks: these are the things we need to worry about. None of them is tightly coupled to GMST. Any of them could conceivably get worse in a low sensitivity world, and any of them could conceivably be unimportant in a fairly high sensitivity world. And, if there is to be adaptation mixed in with the mitigation (as appears likely), these are the things we will need to adapt to or become resilient to.

skanky said...

"And some scientists do tend to fall into the trap of using it, in turn, to defend "global warming theory"."

If there's much overlap between "some scientists" and those mentioned in the OP, then you're possibly looking at scientists (a) defending *their* work from attack and (b) promoting the value of *their* work (which I would presume a great many scientists do).

On the other hand, as climate science makes a prediction of the GMST, both in the past and the future, it makes a straight forward (if mid to long-term) parameter against which to test climate prediction. Thus the disproportionate weighting in political discussion (blogs, media, etc), rather than in the scientific discussions, that I've read.

I find it interesting (unusually so considering the person in question) that someone who's previously messed up GMST trend analysis, and claimed that GMST measuring is biased, and is considered a political expert, should then turn around and say that the main political football in this area is, excuse the pun, overblown.

Lazar said...

linky

Michael Tobis said...

Nice link, Lazar; much to think about therein. Dr. Held provides more sophisticated version of the same claim, in the end, along with some interesting research to consider.