Why Is Climate Sensitivity So Unpredictable?
Uncertainties in projections of future climate change have not lessened substantially in past
decades. Both models and observations yield broad probability distributions for long-term
increases in global mean temperature expected from the doubling of atmospheric carbon dioxide,
with small but finite probabilities of very large increases. We show that the shape of these
probability distributions is an inevitable and general consequence of the nature of the climate
system, and we derive a simple analytic form for the shape that fits recent published distributions
very well. We show that the breadth of the distribution and, in particular, the probability of
large temperature increases are relatively insensitive to decreases in uncertainties associated with
the underlying climate processes.
VOL 318 26 OCTOBER 2007
Publication Date: 2007
DOWNLOAD FILE — PDF document, 279 kB (285,823 bytes)
