Climatologist John Christy: “The Science Is Not Settled”

The New York Times is
running a
pretty fair profile of University of Alabama in Huntsville
(UAH) climatologist John Christy today. As Reason readers
know, I blog
every month the global satellite temperature trend produced by
Christy and his UAH colleague Roy Spencer. I have relied on Christy
as a source of honest data and insight ever since I began reporting
on the science and policy issues related to man-made global warming
over two decades ago. Based on empirical temperature data he has
long questioned the computer climate model projections of rapid and
dangerous warming, which has gained him no friends in what he calls
“the climate establishment.”

From the Times:

John Christy, a professor of atmospheric science at the
University of Alabama in Huntsville, says he remembers the morning
he spotted a well-known colleague at a gathering of climate
experts.

“I walked over and held out my hand to greet him,” Dr. Christy
recalled. “He looked me in the eye, and he said, ‘No.’ I said,
‘Come on, shake hands with me.’ And he said, ‘No.’ ”

Dr. Christy is an outlier on what the
vast majority of his colleagues consider to be a matter of
consensus: that global warming is both settled science and a dire
threat. He regards it as neither. Not that the earth is not heating
up. It is, he says, and carbon dioxide spewed from power plants,
automobiles and other sources is at least partly responsible.

But in speeches, congressional testimony and peer-reviewed
articles in scientific journals, he argues that predictions of
future warming have been greatly overstated and that humans have
weathered warmer stretches without perishing. Dr. Christy’s
willingness to publicize his views, often strongly, has also hurt
his standing among scientists who tend to be suspicious of those
with high profiles. His frequent appearances on Capitol Hill have
almost always been at the request of Republican legislators opposed
to addressing climate change.

“I detest words like ‘contrarian’ and ‘denier,’ ” he said.
“I’m a data-driven climate scientist. Every time I hear that
phrase, ‘The science is settled,’ I say I can easily demonstrate
that that is false, because this is the climate — right here. The
science is not settled.”

Dr. Christy was pointing to a chart comparing seven computer
projections of global atmospheric temperatures based on
measurements taken by satellites and weather balloons. The
projections traced a sharp upward slope; the actual measurements,
however, ticked up only slightly.

Such charts — there are others, sometimes less dramatic but more
or less accepted by the large majority of climate scientists — are
the essence of the divide between that group on one side and Dr.
Christy and a handful of other respected scientists on the
other.

It would have been helpful if the Times had actually
published one of his charts showing the divergence between actual
global temperature trends and computer model projections. Here’s
one such:

And being suspicious of those with high profiles? Oh, please. Do
not leading consensusers James Hansen, Michael Mann, John Holdren,
Kerry Emanuel, and so forth have “high profiles” when it comes to
climate science? As reported by numerous newspapers including the
New York Times, James Hansen famously testified before a
Congressional committee way back in 1988 that “global
warming has begun.”