Thursday, March 13, 2008

Dot earth Discussion of sustainability and SL

Fad, fact, or fusion of possibilities?

Second Life offers us chances to do things that cannot be done easily, or well, in the real world, or cannot be done safely. It also offers a chance to get the pleasures of consumption and travel, without as much of the overhead of hurling people's plasma all over the atmosphere...

Since the dot Earth is slow to update comments, I am going to post mine here. I'm going to start with thanking two people who spent time with me walking me through various points. I'm not, as should be obvious, a climate specialist, but I have passed enough classes on statistics and in the sciences to know scientific method and statistical reasoning. In the comments are two examples of how people lie in the public debate.

I'll start with the easy to dispose of misleading statement, what some people call a "factoid," that is used to try and defuse people's understanding.

"NOAA: Coolest Winter Since 2001 for U.S., Globe"

The image is from wikipedia and the source is listed as:

This image shows the instrumental record of global average temperatures as compiled by the Climatic Research Unit of the University of East Anglia and the Hadley Centre of the UK Meteorological Office. Data set HadCRUT3 was used. HadCRUT3 is a record of surface temperatures collected from land and ocean-based stations. The most recent documentation for this data set is Brohan, P., J.J. Kennedy, I. Haris, S.F.B. Tett and P.D. Jones (2006). "Uncertainty estimates in regional and global observed temperature changes: a new dataset from 1850". J. Geophysical Research 111: D12106. doi:10.1029/2005JD006548.  Following the common practice of the IPCC, the zero on this figure is the mean temperature from 1961-1990.

This graph shows that while 2007 was indeed "the coolest year since 2001" this is only because we've had the cluster of warmest years on record. In fact, the headline could have been about how 2007 continued an abnormal cluster of very warm years. According to a mathematically inclined friend, last year is a further indication that something unusual is going on with climate, because under ordinary circumstances is a "wavelet oscillator," something which has a pattern of bouncing up and down over its general trend line. According to him oscillators are common in climate, I know they are common in biology. When an oscillator pattern ceases to be observed, it's an indicator of something within the model. He enumerated several possibilities, some of them affirming the hypothesis that something was disturbing the underlying system, and others that the system had what he called "an equilibrium" form. He pointed me to a recent paper on fish populations which showed that the relationship between a particular fish and its prey tended to either engage in wide swings, or remain very close to stable, but that transitions between these two states were considered to be an inidication of an outside disruption. He then mentioned some cases where the clustering against an oscillator was the indication of a local peak in a long term pattern.

What that means, I think, is that last year being slightly cooler probably means that global warming is confirmed, in a minor way, by the fact that while it was cooler, it was not much cooler, when ordinarily we would have expected a cooling year to show a significant drop below the best curve fit. You can see this from the graph, with a few exceptions, generally the wobble of global temperature is a cluster of warm years, perhaps a transitional year, then a cold year, or perhaps two, then possibily transition, and then back to warm years. Since the long term trend has been up, generally there are more warm years in a peak than cold years. That we've had such a large cluster of warm years is very unusual.

His last warning however was that you can go crazy staring at the charts too long, and it is always best to get back to data, experiments, and theory. By theory he meant mathematical descriptions of data that predicted the outcome of experiments.

That brings me to the latest echo boom in the right wing, a claim by a former NASA scientist that the equations used for climate prediction are "totally wrong." He hasn't presented his views widely, and I just got back an email from a friend in Europe who has looked at his original (which I could not find initially.) Here is the original.

His response was that the paper has several assumptions which are not proven, and which are crucial to the conclusion. He pointed me to which pointed to the most important one. To unpack what is being talked about, let me cite from the original paper:

identify EU as the total internal kinetic energy of the atmosphere, the
EU=SU/2 equation must hold. EU can also be related to GN through the
EU=SU(A-GN) equation. In opaque atmospheres 1=A and the 0.5GN = is
the theoretical upper limit of the normalized greenhouse factor.

According to Arthur Smith, this isn't established. Or more specifically, since SU/2 = SU(A-GN) is trivially the same thing, these aren't different equations, since A=1 and G<.5 means that this is:

SU*.5 = SU/2 * (1-.5)
.5 = .5

Without showing that there's any cause relationship between the two. The relationship doesn't have to hold, my friend explains, because he's simply multiplying both sides of an equation by constants and numbers that he's arbitrarily asserted.

My friend then went on to point out that on page 8:

It is practically the / UOLRS ratio
or the normalized OLR. The greenhouse functions are analogous to the
empirical NG factor introduced in Section 2.

That there are two assertions here, one is that the ration is "practically" the same, which would require proof that there are no other significant factors, which since this is what is being argued, makes the argument circular, and that being "analogous" isn't a transparent assertion either, Maxwell's inverse square law is analogous to Newton's, he said, but that doesn't mean you can swap one for the other.

Caught in this web of circular assertions and unproven assumptions, he draws a conclusion that doesn't work in the face of experimental evidence, that some gases do, in fact, allow some wave lengths of light to pass through, striking the earth below, which re-emits them as different wave lengths, that are then reflected or absorbed by the atmosphere and not radiated back to space.

Instead the paper asserts on page 9:

The popular explanation of the greenhouse effect as the result of the LW
atmospheric absorption of the surface radiation and the surface heating by the
atmospheric downward radiation is incorrect, since the involved flux terms
( AA and DE ) are always equal.

But he hasn't proven this, he asserted the hydrostatic equilibrium, he didn't prove it, since his proof is that it is empirically and pratically analogous, and there is nowhere a survey of data that shows this, or a citation to anyone else's survey of the data that shows this.

Instead he proposes:

The mechanism of the greenhouse effect may
better be explained as the ability of a gravitationally bounded atmosphere to
convert F0 P0+ to OLR in such a way that the equilibrium source function
profile will assure the radiative balance ( F0 P0 = OLR ), the validity of the
Kirchhoff law ( ED=SUA), and the hydrostatic equilibrium ( SU=2EU [my note, these are the equations mentioned in the previous excerpts).
Although an atmosphere may accommodate the thermal structure needed for the
radiative equilibrium, it is not required for the greenhouse effect. Formally, in
the presence of a solid or liquid surface, the radiation pressure of the thermalized
photons is the real cause of the greenhouse effect, and its origin is related to
the principle of the conservation of the momentum of the radiation field.

My friend notes that this is hand waving, that everyone admits that most of the heat stored in the atmosphere and oceans is because of the molecules themselves, but that the question of global warming is not about most of the heat storage, but about a rather small variation in the total which will make life very uncomfortable for us. And his proof is handwaving away small effects. I can understand that, a myocardial infarction, a heart attack, doesn't involve many cells as a total of the body. Most of the body is just fine, except...

At most, he tells me, that this paper argues against the kind of runaway heat death fears, which postulate that earth will become like Venus, which, he notes, is also not accepted in the scientific literature.

I'm going to underline that I am not a climate scientist, I could have misinterpreted what the blogger and my correspondent have said, and that all of this needs to be checked. But it hasn't been in an uncritical amplification of the paper by a variety of sources, none of whom have checked the numbers in any shape manner or form, and have, it seems, even less qualifications to do so than I do.

1 comment:

  1. Sarah
    Saw your comment on Dot Earth and came here to visit. looking forward to your new blog on the lecture tonight. Will tune in tomorrow for an update.

    As an educator based here in Taiwan, an island far far away from DC, looking forward to reading more of your blog and hope that someday you can blog to your student readers about my VIRTUAL JAMES LOVELOCK MUSEUM OF POLAR CITY IMAGES: I think students will be inspired by these images to come up with their own ideas about future adaptation strategies....

    Do take a look:

    Danny Bloom
    Tufts 1971