Science in international negotiations
The Climate Change Convention: a load of hot
By Peter Hulm
The problems of consensus
At the end of 1991 Greenpeace polled the 400
climate scientists for their opinions on global warming ( New
Scientist , 1992). Of 113 who returned the questionnaires
(ibid), about half thought a runaway greenhouse effect possible
if no mitigating measures were taken (Leggett, 1993:46). Some
13 percent thought it probable (ibid). Leggett notes: "This
worst-case analysis was not articulated in the IPCC report"
and described the acceptance of lowest common denominators in
the consensus as "a partial failure of the science advisory
Boehmer-Christiansen (1995:3) goes further: "This
informed IPCC opinion or set of negotiated best guesses reflects
the conclusions not of the scientific community, which
has no recognised process of consensus creation and would be
shocked by the idea, but of a group identified as a handful
of research managers close to a small number of governments."
Not surprisingly, these governments were among the most active
in the negotiations, if not in action to reduce emissions of
so-called greenhouse gases.
Whatever the consensus achieved in 1992, it was
no foregone conclusion. In his history of scientific opinion
formation about acid precipitation, stratospheric ozone depletion,
and global warming, a Republican Presidential advisor in the
US, Michael Kowalok, points out that a pioneering 1985 meeting
in Villach, Austria, bringing together climate scientists from
29 developed and developing countries, reached conclusions that
"sharply conflicted with the conclusions of earlier groups"
(Kowalok, 1993:36). He also noted that many researchers into
these environmental issues were sceptical about the theories
and even about their own research findings until they were able
to exchange information with colleagues from around the world
The panel chair admits: "IPCC's conclusions have
been criticized in Nature, other parts of the scientific
literature and, to a greater extent, in the popular press, mainly
for lack of openness about uncertainties and for brushing aside
controversies" (Bolin, 1994). However, Bolin also argued that
only "a few scientists [...] believe that little can be said
about future climate based on our present knowledge" (ibid).
Among those criticizing the IPCC assessment,
the most respected is probably Professor Richard Lindzen of
the Massachusetts Institute of Technology. Even Leggett (1993)
describes him as a "world class meteorologist."
Among climate scientists, however, there is no
doubt that Lindzen represents a minority view. Further, his
associations with industry have made him suspect (see below).
In fact, the IPCC academic opponents influential
in US official circles have all come from outside the meteorological
community. Professor William Nordhaus, for example, is a Yale
University economist. The campaigning environmental magazine
The Ecologist remarked: "Nordhaus's views on global warming
are neither an aberration within his profession nor are they
without consequence" (1992:42). John Gribbin further reported
that the two scientists who had President Bush's ear in their
criticisms of the IPCC consensus were an astronomer and oceanographer
The problems of consensus