Tuesday, October 21, 2008

No No Nierenberg or the wabid wabbit attacks


Here begins a new chapter for the William Nierenberg Book Club. If you have not been paying attention, places to catch up include Stoat, Stoat, Stoat, Atmoz, Nierenberg Central, and yr. humble hare here, here and especially here for the background to this post.

To make a long and a short of it, William Nierenberg was a founder of the George Marshall Institution with Robert Jastrow and Fred Seitz, president of the Scripps Institute, a member of the National Academy, etc. He is not especially a favorite of Naomi Oreskes, who has assigned him considerable responsibility for blocking early action on climate change (read the links damn it!!).

While those other characters have been looking at Jason and NAS reports (read the links damn it), Eli has acquired at considerable cost ($0.41 + postage) a copy of Scientific Perspectives on the Greenhouse Problem, by Robert Jastrow, William Nierenberg and Fredrick Seitz (nice to see that they followed the mathematicians practice for author lists) published by the Marshall Institute in 1990.

The first 61 pages are by the JNS team, and Eli assumes for convenience that perhaps with some small changes, they are the same as the manuscript circulating in 1991 which was described by Jerry Mahlman as "noisy junk".

The book is being read by the bunny book club but Eli thought he would give you a taste of the thing starting with Figure 1.

Fig. 1 Comparison between observed global average temperature and calculations by Hansen, et al. (2) based on a computer simulations of the greenhouse effect. the dashed line indicates the calculated temperature increase caused by carbon dioxide increases since 1880. The solid line indicates the observed temperatures for the same period. The zero point in the calculated curve has been adjusted to agree with observations for the 1880s, since nearly all the anthropogenic greenhouse warming occurred subsequent to that time. both curves show a 0.5 C rise over the 100 year interval, However, the observed temperatures, unlike the calculations, show a rapid rise in the first 50 years followed by a decrease from 1940-1970.

Young and innocent readers, let us see why this is a fitting entry into the 1990 Golden Horseshoe Award.

Of course, Eli will not be able to find all the goodies and welcomes participation. Now the first thing you ask, (and it is but a small thing as pointed out in the comments but indicative-added) this book was published in 1990, why does the x-axis end about 1983 (a relatively cool year. Why glad you asked, the temperature went up from there as you can see in the figure from global warming art opposite. Further

The zero point in the calculated curve has been adjusted to agree with observations for the 1880s, since nearly all the anthropogenic greenhouse warming occurred subsequent
So JNS increased the calculated effect of CO2, assigning all of the change in global temperature since 1880 to increases in CO2 concentration. Eli wonders, is that what Hansen, et al (2) did? Well no, but glad you asked so let us look at Climate Impact of Increasing Atmospheric Carbon Dioxide by J. Hansen, D. Johnson, A. Lacis, S. Lebedeff, P. Lee, D. Rind and G. Russell. 28 August 1981, Volume 213, Number 4511
Summary. The global temperature rose by 0.2 °C between the middle 1960's and 1980, yielding a warming of 0.4°C in the past century. This temperature increase is consistent with the calculated greenhouse effect due to measured increases of atmospheric carbon dioxide. Variations of volcanic aerosols and possibly solar luminosity appear to be primary causes of observed fluctuations about the mean trend of increasing temperature. It is shown that the anthropogenic carbon dioxide warming should emerge from the noise level of natural climate variability by the end of the century, and there is a high probability of warming in the 1980's. Potential effects on climate in the 21st century include the creation of drought-prone regions in North America and central Asia as part of a shifting of climatic zones, erosion of the West Antarctic ice sheet with a consequent worldwide rise in sea level, and opening of the fabled Northwest Passage.
The NW Passage has indeed opened in the last two years, but didn't you get the idea from Bob, Bill and Fred that Jim and his buddies assigned all the the change since 1880 to CO2? Guess again, what Hansen et al. actually tried to do was to constrain the climate sensitivity and changes in the solar constant to obtain the best fit to observations This WAS published in 1981 and the models were considerably less sophisticated, almost as unsophisticated as the denialists claim now.
Radiative forcing by CO2 plus volcanoes and forcing by CO2 plus volcanoes plus the sun both yield a temperature trend with a strong similarity to the observed trend of the past century (Fig. 5), which we quantify below. If only the heat capacity of the mixed layer is included, the amplitude of the computed temperature variations is larger than observed. However, mixing of heat into the deeper ocean with k = 1 cm2 sec-1 brings both calculated trends into rough agreement with observations.

The main uncertainties in the climate model-that is, its "tuning knobs"-are (i) the equilibrium sensitivity and (ii) the rate of heat exchange with the ocean beneath the mixed layer. The general correlation of radiative forcings with global temperatures suggests that model uncertainties be constrained by requiring agreement with the observed temperature trend. Therefore, we examined a range of model sensitivities, choosing a diffusion coefficient for each to minimize the residual variance between computed and observed temperature trends. Equilibrium sensitivities of 1.4°, 2.80, and 5.6°C required k = 0, 1.2, and 2.2 cm2 sec-1, respectively. All models with sensitivities of 1.4° to 5.6°C provide a good fit to the observations. The smallest acceptable sensitivity is - 1.4°C, because it requires zero heat exchange with the deeper ocean. Sensitivities much higher than 5.60C would require greater heat exchange with the deep ocean than is believed to be realistic (21, 22). Radiative forcing by CO2 plus volcanoes accounts for 75 percent of the variance in the 5-year smoothed global temperature, with correlation coefficient 0.9.
and they get a pretty fair agreement. They go on to discuss
The predicted CO2 warming rises out of the lσ noise level in the 1980's and the 2σ level in the 1990's (Fig. 7). . . Nominal confidence in the CO2 theory will reach - 85 percent when the temperature rises through the lσ level and - 98 percent when it exceeds 2σ. However, a portion of a may be accounted for in the future from accurate knowledge of some radiative forcings and more precise knowledge of global temperature. We conclude that CO2 warming should rise above the noise level of natural climate variability in this century.
Is that a slinky little beast raising his hand in the audience? Well what say you: "Look Hansen, et al. only went out to 1980, just like Jastrow, Nierenberg and Seitz. Well sadly no. JNS went to 1982-3, just when the cooling trend from the El Chichon eruption kicked in and they published in 1990. Hansen, et al. published in 1981. Somehow the Marshall gang managed to avoid almost a decades worth of improvements in the models since 1981.

Will someone please reassert Eli's faith in the innocent as melting snow Bill Nierenberg.

9 comments:

Magnus said...

Also worth to read...

http://climateprogress.org/2008/10/21/population-growth-and-climate-the-eu-15-vs-the-us/

Belette said...

Hi Eli. I think this is a confusing post. As far as I can tell, the real point here (apart from writing in 1990 and using a paper from 1981, when H must have written in the interim) is that JNS have used the CO2-only curve, when H et al clearly show that you get better agreement, as you would expect, from using CO2+vol+sun.

SO JNS are being deliberately misleading about the 1981 H paper, making the natural assumption that you've quoted fairly.

But ending in 1985 when writing in 1990 might be a bit dodgy, but not very: people didn't trade series as quickly as they do now; you'd need to show that 1986-1990 was conveniently available to convict them on this score. Putting that as your first point just confuses the issue. Its trivia.

EliRabett said...

There were some funny html insertions which corrupted the text. Sorry. But you do note that JNS were distorting what Hansen et al wrote. The Hansen paper is also interesting because it got many things right and because of the things that it got wrong. Basically it used observational data to set limits on the processes that control climate which is very much what James and Julia did.

EliRabett said...

Oh yeah, the 1985 was an about.

If you look closely they cut off as El Chichon had kicked in, so even 1985 would have been an upturn. As to what was available to them, I point you to

Hansen, J., I. Fung, A. Lacis, D. Rind, Lebedeff, R. Ruedy, G. Russell, and P. Stone, 1988: Global climate changes as forecast by Goddard Institute for Space Studies three-dimensional model. J. Geophys. Res., 93, 9341-9364, doi:10.1029/88JD00231.

Hansen, J., and S. Lebedeff, 1988: Global surface air temperatures: Update through 1987. Geophys. Res. Lett., 15, 323-326, doi:10.1029/88GL02067.

and an endless number of other updates and models. You cannot be seriously claiming that JNS did NOT have access to this data, because the data is what they were trying to obscure and it was the extremely (for up to then) hot years of 87-89 that brought the issue to the fore.

Anonymous said...

This is a lot of pointless fuss about a marginally interesting 10 or maybe 20 year old paper, anyway, well older than 1998, its difficult to see why warmers keep obsessing about this unimportant guy and Marshall Institute, who no-one would have heard of if they would just shut up about him, and the conclusions have been confirmed by lots of other independent peer reviewed studies anyway, and anyway, it is surely TIME TO MOVE ON?

Anon 11.17

EliRabett said...

Well, actually it is about a rather influential guy, who influenced a lot and left behind a rather influential policy place and no, if you look at what they drag in they ain't going away.

Ethon could have said the same about Roger Jr., but he keeps pecking away.

Caroline said...

Mr. Rabett,

I also was a bit confused by this post. Clearly the dotted line for temperature increases from CO2 was not the same line as the Scenarios (A,B,C) in Dr. Hansen's paper. I am traveling and don't have all this in front of me. It seems to me that the dotted line simply represents the temperature increase from sensitivity to CO2 as postulated by Hansen without considering other forcings.

The Marshall paper pointed out that the measured temperature increases don't track that line, although they wind up at the same point. This is clearly a true statement, although it doesn't seem to me that this proves anything one way or the other.

I believe they go on to list the reasons, like aerosols, that people have used to explain the differences. They say something like this has an ad hoc feeling to them.

In any event, hardly a smoking gun of denialism.

Nicolas Nierenberg said...

Sorry the last post was from Nicolas Nierenberg. Didn't notice that my wife was logged in on this computer.

Anonymous said...

Nicholas Nierenberg's wife's husband posted "I believe they go on to list the reasons, like aerosols, that people have used to explain the differences. They say something like this has an ad hoc feeling to them."

By that logic, any effect that has multiple "causes" (ie, that is not attributable to single cause) would have an "ad hoc feel to it".

The application of the terminology "ad hoc" to this case is actually very poor, at any rate:

"Ad hoc is a Latin phrase which means "for this [purpose]". It generally signifies a solution designed for a specific problem or task, non-generalizable, and which cannot be adapted to other purposes."

The concept of "radiative forcing" is actually quite general and applies not only to CO2 but to many other things that can induce surface temperature changes.