| Wednesday,
December 23, 2009 A Climate Debate of
sorts:
From another conference:
This is a good summary of the consensus
position:
Science issues and
policy issues [Re: URL for NOAA Ice Core Charts]
Once more: The
greenhouse effect is part of the laws of physics. The reason that
scientists pretty much dismiss the skeptics out of hand is that, as far as
I'm aware, NONE of them have come up with a plausible alternative
explanation for why adding carbon dioxide should *not* increase the
temperature of the Earth.
(Let me remind you that
the natural greenhouse effect is about 30 degrees C: without an
atmosphere, the Earth's radiative equilibrium temperature would be below
freezing. The anthropogenic contribution is, in fact, a pretty small
perturbation).
It's fine enough for
amateurs to pick through the enormous data record of climate science and
say "wait, what about this curve? How about this one?", but this,
actually, is not science. The correct way to do science would be to try
to fit those curves to a model, and see how they fit.
Is there a model in
which carbon dioxide does NOT cause greenhouse effect warming WHICH FITS
THE CURRENT DATA?
Here is the greenhouse
effect physics, in a nutshell:
1. the warm Earth emits
infrared radiation.
2. some portion of that
infrared is absorbed by (infrared-absorbing gasses in) the atmosphere.
3. the atmosphere
re-emits that absorbed energy in the from of infrared, isotropically.
4. Some of the infrared
radiation emitted from the sky is absorbed by the Earth.
These are all pretty
straightforward physical processes (that have been known for a century);
if you like you can measure the downwelling infrared with an infrared
bolometer, and even spectroanalyze it. This is not new physics. It is
covered, for example, in book-length detail in the copy of _Introduction
to Atmospheric Radiation_ (1980) on my bookshelf, not to mention dozens of
other texts.
Let's suppose that there
is, actually, some (as yet invisible) reason to be skeptical. I will
suggest that the current crop of
"skeptics" have
*damaged* our ability to find it. Overall:
-they ignore
back-of-the-envelope physics calculations
-they don't believe
detailed physics calculations based on integrating the absorption spectrum
-they dismiss all the
detailed numberical-integration atmospheric models
-they discard the
measurements when they doesn't agree with the conclusion they started
with.
Basically, once you
discard all the tools that they don't like the results of, there aren't
any tools left to do science with.
So: we have a serious statement by a serious person, who wants to
discard the skeptics and get on with it since the science is settled.
My first critique is simple:
Historically, warming precedes rises in CO2. This is in accord with
normal theory. While it is certainly true that a 'greenhouse effect"
influences climate, historically, CO2 levels have not caused warming; the
CO2 levels follow a temperature rise, not precede it.
Arrhenius thought:
(1) that temperatures were rising and had been since 1800. Correct.
Historical data. Not a prediction. Observed through through the 1800's.
(2) They would continue to rise as they had been rising. This was more or
less projection of an existing trend. That would be about a degree per
century. As it happened, the observed temperature rise decelerated (and had
been decelerating for a few years) when Arrhenius made that prediction, but
temperatures did rise. The NOAA data show 1880 as -.2 below the 1940
"normal" of 0, and "normal" or 0 in 1940. That's not the 0.5 predicted but
the trend is in the right direction.
(3) Arrhenius predicted that there would be an "extra" rise of about 2
degrees over a century if CO2 levels doubled. This is theory. It is now 110
years since he made that projection. We have had under 2 degrees rise in
that time period according to the NOAA data. That is, from 1940 to 2003 it
went up about 0.4 degrees. There is a sort of "hockey stick" sharp rise from
2000 to 2009 but these data are a bit controversial. We can agree on about
0.7 C rise =~ to 1.7 F from Arrhenius to now. It's less than expected, but
it is a rise. Call it a full degree C (1.7 F) rise if you like.
(4) you may ascribe that 1 C rise to CO2 if you like, in which case you
have to throw out the projection of a continued "normal" 1 C rise that would
have happened without CO2. You may ascribe that 1 C rise to the "normal
trend" that has been taking place since the end of the Little Ice Age. You
don't get both, because the data show only the 1 C rise, at least as close
as I can read the NOAA charts.
Why? We don't have a good theory as to why; but those are the data, and
the usual practice in science is that theory has to account for data, not
data have to be forced to fit the theory.
Now about the simple back of the envelope accounts: As Dyson points out,
CO2 can have an effect only in COLD DRY AREAS. There isn't much room for
"greenhouse" warming in moist areas. Greenhouse effects may -- indeed must
-- be involved in the temperature of the Earth, but clearly we don't have a
good quantitative handle on which ones do what: but surely we can agree that
CO2 isn't what's happening.
Or: if it is CO2, then the fears of the 1970-1984 doomsters who feared a
coming Ice Age are very well founded and the CO2 is what saved us. This is
sort of what Niven, Flynn, and I projected in Fallen Angels.
That was a work of fiction, and as I have often said, novelists need only be
plausible: we don't have to marshal all the arguments for our case as do
advocates, and we certainly do not have to account for all the data.
Scientists, however, do have to account for all the data, and none of the
current models do that.
One theory common in the 1970's was that warming brought out more
moisture, which moved more water vapors around, which was increasing snow
falls and that was what was causing the new disastrous coming New Ice Age
and Global Cooling that had scared Schneider and Margaret Meade and others,
and dominated big science conferences during the 70's and early 80's.
What we must conclude is that the models have not predicted what we have
observed; nor have we found the stratospheric hot spots that CO2 driven
warming predicts we will find. This is not a confirmation of the accuracy of
the theories, all of which more or less predict the same results -- which
results have not been found so far.
For decades we have had two kinds of climate scientists: theorists and
observers. The theorists are all pretty strong Global Warming advocates. The
observers are a mixed lot, but none of them see what the models predict. The
believers among them say "we have not seen them yet."
More theory: if I want to put CO2 into the atmosphere, I can burn coal
and oil, but if I really want to run the CO2 levels up I should warm the
seas. I want to bring up a lot of cold water to the surface and warm that.
Warming the oceans will really raise the CO2 levels; how much CO2 for how
much temperature rise is calculable, but getting that circulation
going is a bit more complicated, and we don't seem to be able to predict El
Nino and La Nina events which have great effects on ocean surface
temperatures. As a first cut, I will not try to warm the seas by blowing
warm air over them. If I want more cold water to come higher, I'll turn on
the heat down at the bottom -- otherwise known as volcanic events. Those of
course are unpredictable, at least at present.
But if I want something to worry about, I'll worry about how to remove a
great big lot of CO2 that we could get if the oceans do warm. That could
really cause a runaway hockey stick temperature rise. Could. It's not
inevitable. I'd think some investment in developing engineering methods to
really clean out CO2 from the atmosphere would be prudent. We may not need
the techniques, but if we do, we are going to need them bad.
So: I don't think Dyson and Baliunas and Singer and the other skeptics
are ignoring the back of the envelope calculations: but they are pointing
out that the data don't seem to be reconciled with the theory. As to "-they
dismiss all the detailed numberical-integration atmospheric models"
perhaps they should until the detailed numerical models can take a set of
initial conditions and generate a good fit to what actually happened.
As to the greenhouse effect itself, who ever thought there wasn't one?
And perhaps that is what is saving us from living on a ball of ice. Perhaps
not. But I fail to see how investing in better models -- they get better
when questioned, and I doubt they get better by setting up "peer review" so
that anything that doesn't approve of the -the
detailed numberical-integration atmospheric models
gets ignored.
Present policy seems to be to spend billions in ways that will have a
pretty small effect on the CO2 released into the atmosphere and even less
effect on the actual warming -- this according to
the detailed numberical-integration atmospheric models which
show that Kyoto would have had the effect of preventing well under 1 C of
the projected temperature rise. The costs run to the trillions.
That's not good policy. Prudent policy would try to understand what is
going on before spending big money to change the entire economy.
AND SEE MAIL
=====================
Ursula LeGuin resigns from Author's Guild, citing Google Settlement.
http://www.ursulakleguin.com/Note-AGResignation.html
I need to think on this one. Meanwhile
So much for Kindle DRM
<http://www.theregister.co.uk/2009/12/23/amazon_kindle_hacked/>
<http://pastie.org/753699>
Looks like e-books are now in the same boat that
audio CDs and DVD videos have been in for years. No more DRM. The
publishers are going to freak, not to mention Amazon.
-- Robert Bruce Thompson thompson@ttgnet.com
I am thinking about this one -- well, translate, my advisors are
discussing it and I'm listening. More to come.
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