"nuclear winter"

[palmer@sfu.ca (Leigh Palmer)]

Dewey asks:

> Isn't it the case that regardless of the sign and magnitude of a
> temperature change, enough particulate material would be distributed in the
> atmosphere to have serious effect on plant growth and to distribute enough
> biologically damaging residual radioactive materials to compound this
> problem?  Such a disruption at the basal level of the food chain seems to
> indicate major consequences for the human population of the Earth.  Isn't
> this the point, regardless of the specifics of the model?

I'm sorry, Dewey, but that sounds like Greenpeace rhetoric. I'm afraid
that genre brings out the worst in me. I apologize in advance for any
disruption of ideas I may cause in my eruptive state.

In science the question is usually cast in quantitative rather than
emotional terms. I want to reassure everyone on this list that I, too,
disapprove of nuclear war. Science can be applied to this problem (I'm
also a reductionist, I'm afraid) and perhaps some useful results can be
obtained from that application. On the other hand, perhaps our science
has not yet advanced to the stage necessary to do that with high
confidence; maybe we don't yet know enough.

The Sagan et al. (should be Turco et al., but who would recognize it?)*
paper certainly does not inspire confidence in the present state of
knowledge. It is saying no more than an admonishing parent or preacher
who tells you there will be dire consequences if you do a forbidden
deed. Well, I'm here to tell you, no more nor less authoritatively than
Carl Sagan, war is bad. Don't do it. Nuclear war is even worse than
"conventional" war. Sagan invokes the bogey man to dissuade me from war.
I find that objectionable because he does it in my church, invoking bad
science to belabor the obvious with unsupportable hyperbole.

> What exactly is it that was new in the Sagan, et al., 'Nuclear Winter'
> article which turns out to be wrong?

The predictions, which, in turn, are derived from a fundamentally flawed
model which was the scientific meat of the paper**. The final refutation
came from experiment. In January 1991 Sagan predicted serious global
consequences from Sadam Hussein's setting alight the Kuwaiti oilfields
based on the nuclear winter model, likening it to the effect of Tambora
in 1816. While there was severe local environmental damage, the global
effect, if detectable at all, was much smaller than he had predicted.

Incidentally, in my browsings I have learned that indeed 1883 was not
the "year without a summer", as someone else stated in this discussion.
That conforms to my earlier memory. It was 1816, after the eruption in
1815 of the Indonesian volcano Tambora. I just thought I should clear
that up.

Leigh

**Turco, RP; Toon, AB; Ackerman, TP; Pollack, JB; Sagan, C
  Nuclear winter - Global consequences of multiple nuclear explosions.
  Science, 1983; vol. 222 (4630): pp. 1283 - 1292
  Look that up in your Science Citation Index.

**I have found, from a secondary source, excerpts from the "News and
Comment" section of "Science" which I include to lead Dewey and others
to "exactly" what is wrong with the analysis of Sagan et al. It is old
stuff, and I don't want to follow it farther back.

  A study by the National Center for Atmospheric Research suggests
  most of the world would experience a mild nuclear winter, not a deep
  freeze... (however) the best known presenter of the original theory,
  Carl Sagan of Cornell, claims there is 'nothing new' to make him
  alter his description of nuclear winter or the conclusions drawn
  from it... Sagan's refusal to acknowledge merit in the NCAR's (Nat.
  Cent. for Atmos. Res.) analysis - known as 'nuclear autumn' - sends
  some people up the wall. One wall climber is George Rathjens,
  professor of political science at M.I.T... 'Is this another case of
  Lysenkoism?' he asks, referring to an erroneous genetic theory
  forced on Soviet scientists in the late 1940's... Rathjens answers
  himself: 'I am afraid there's a certain amount of truth in that. The
  claim that 'the original nuclear winter model is unimpeached', he
  adds, is 'the greatest fraud we've seen in a long time'... [this has
  led to other criticisms of Sagan's theory]. One such attack by
  Russell Seitz, a fellow et Harvard's Center for International
  Affairs, appeared recently in The National Interest, a Washington
  D.C. quarterly, and the Wall Street Journal. Seitz. who is not a
  diploma-holding scientist gibes at TTAPS's [Sagan and his co-authors]
  for mixing of physics and advertising. Seitz notes that Sagan
  published the nuclear winter thesis in Parade magazine a month
  before it appeared In Science. He writes: 'The peer review process
  at Parade presumably consists in the contributing editor conversing
  with the writer, perhaps while shaving -- Sagan is both.' Anyone who
  wants to verify the data on which the conclusions were based,
  according to Seitz, has to set off on a paper chase' [Sagan's
  conclusions] rested on an unpublished... Science article, 'details
  may be found in (15).' Reference 15 states ln full: 'R.P. Turco. O.B.
  Toon, T.P. Ackerman, J.B. Pollack, C. Sagan in preparation.' It
  refers to a paper that has never been published in a peer-reviewed
  (or any other) journal. Rathjens also grumbles about the hard to get
  data. The entire thesis, he says. is 'a house of cards built on
  reference 15.'.

**Turco, RP; Toon, AB; Ackerman, TP; Pollack, JB; Sagan, C
  Nuclear winter - Global consequences of multiple nuclear explosions.
  Science, 1983; vol. 222 (4630): pp. 1283 - 1292
  Look that up in your Science Citation Index.