Page 279 - James Rodger Fleming - Fixing the sky

funding, a single agency with deep pockets—for example, the Department
of Energy, NASA, or even the Department of Defense or Homeland Security—
is not the way to go. Neither is a private company in which commercial goals
may overwhelm scientific objectivity. This field needs enhanced public input
and open peer review, such as that provided by the National Science Foundation.
Recently, atmospheric scientist William Cotton pointed out the relationship
between weather engineering and climate engineering, along with their system-
atic problems and structural differences. In weather modification experiments,
the scientific community requires “proof ” that cloud seeding has increased pre-
cipitation. Following an intervention, such proof would include “strong physical
evidence of appropriate modifications to cloud structures and highly significant
statistical evidence”—that is, effects that exceed the natural background vari-
ability of the atmosphere. But intervention is not control. In 1946 Kathleen
Blodgett at General Electric told Irving Langmuir that intervening in or modi-
fying a cloud was a far cry from controlling its subsequent motion and growth
or the characteristics of its precipitation. Having experienced the promise and
hype of cloud seeding, and after having worked for fifty years in this field, Cot-
ton admitted, “We cannot point to strong physical and statistical evidence that
these early claims have been realized.” 100 He went on to note that proof of suc-
cess in climate engineering would be far harder to establish than in weather engi-
neering. In fact, it would be impossible, for several reasons: climate models are
not designed to be predictive, so there is no forecast skill; global climate experi-
ments cannot be randomized or repeated and cannot be done without likely
collateral damage; climate variability is very high, so the background-noise-to-
signal ratio is overwhelming; and climate change is slow to develop because of
built-in thermal lags due to oceans and ice sheets. What all this adds up to is that
experimental “results” could not be established even within the experimenters’
life spans. Did I mention the chaotic behavior of the climate system? That alone
would overwhelm any attribution of experimental interventions by climate
engineers. Cotton warned that in times of drought or climate stress, politicians
would emerge with the need to demonstrate that they were doing something,
that they were in control of the situation, even if they only enacted what he
called political placebos.

the middle Course

In 1983 Thomas Schelling outlined four basic policy choices for responding to
carbon dioxide–induced climate change:

262 | tHe Climate enGineerS