01 April 2010

Der Spiegel on Climate Science

Der Spiegel has a really great, long article (in English) on the troubles facing the climate science community (the image above is from Der Spiegel's 1986 cover story on climate change). The article characterizes current debate in blunt terms:
A religious war is raging between alarmists and skeptics, and it threatens to consume levelheaded climatologists.
The article has a very interesting and new (to me, at least) discussion of the CRU temperature data that was given by Phil Jones to Georgia Tech's Peter Webster that will no doubt tantalize those looking to find something amiss in global temperature records:
Under the pressure of [Steve] McIntyre's attacks, Jones had to admit something incredible: He had deleted his notes on how he performed the homogenization. This means that it is not possible to reconstruct how the raw data turned into his temperature curve.

For Peter Webster, a meteorologist at the Georgia Institute of Technology in Atlanta, this course of events is "one of the biggest sins" a scientist can commit. "It's as if a chef was no longer able to cook his dishes because he lost the recipes."

While amateur climatologist McIntyre spent years begging in vain for the raw data, Webster eventually managed to convince Jones to send them to him. He is the only scientist to date who has been given access to the data. "To be honest, I'm shocked by the sloppy documentation," Webster told SPIEGEL.

Unnoticed by the public, Webster has spent several months searching for inconsistencies in the Jones curve. For example, it has been known for some time that there are noticeable jumps in ocean temperature readings. The reason for the inconsistencies is that, beginning in the 1940s, water temperature was no longer measured in buckets filled with seawater, but at the intake valves for the water used to cool ship engines.

But when he analyzed Jones's data, Webster discovered suspiciously similar jumps in temperature -- but on land. "Water buckets can't explain this," says Webster.

The Jones team attributes another sudden jump in temperature readings to the decline in air pollution since the 1970s as a result of stricter emissions laws. Particles suspended in the air block solar radiation, so that temperatures rise when the air becomes cleaner. Air pollution in the south has always been much lower than in the north, because, as Webster explains, "there is less land and therefore less industry in the Southern Hemisphere."

Oddly enough, however, the temperature increase in the south is just as strong as it is in the north. "That isn't really possible," says Webster.

Webster doesn't believe that inconsistencies like these will invalidate the Jones curve altogether. "But we would like to know, of course, what's behind all of these phenomena." If a natural mechanism were at least partly to blame for the rise in temperatures, it would decrease the share of human influence in current global warming.

Hans von Storch explains what is needed to regain lost trust:

German climatologist Hans von Storch now wants to see an independent institution recalculate the temperature curve, and he even suggests that the skeptics be involved in the project. He points out, however, that processing the data will take several years.

"There is no other way to regain the trust that has been lost," he says, "even if I'm certain that the new curve will not look significantly different from the old one."

And if it does? "That would definitely be the worst-case scenario for climatology. We would have to start all over again."