by Margot Roosevelt in the Los Angeles Times:

An effort by a handful of UC Berkeley scientists to reexamine temperature data underlying global warming research has landed in the center of a national political debate over government regulation.

The Berkeley Earth Surface Temperature study is led by physicist Richard Muller, a longtime critic of the scientific consensus on climate change, who plans to testify on the effort Thursday before the House Science Committee in the latest of several congressional inquiries on climate science since the GOP majority was seated.

The Berkeley project’s biggest private backer, with $150,000, is the Charles G. Koch Charitable Foundation. Oil billionaires Charles and David Koch are the nation’s most prominent funders of efforts to prevent curbs on fossil-fuel burning, the biggest contributor to planet-warming greenhouse gases….

The Berkeley effort is hardly new. Over the last two decades, three independent scientific groups have analyzed international data from thousands of weather stations. Using different combinations of stations and varying statistical methods, all have come to nearly identical conclusions: The planet’s surface, on average, has warmed about 0.75 degrees centigrade (1.4 degrees Fahrenheit) since the beginning of the 20th century.

Scientists involved in those studies said they would welcome new peer-reviewed research, but they contend that Muller is violating scientific protocol by publicizing his project, underway for months, before it produces any vetted scientific papers.

“I am highly skeptical of the hype and claims,” said Kevin Trenberth, who heads the Climate Analysis Section of the National Center for Atmospheric Research, a university consortium. “The team has some good people but not the expertise required in certain areas, and purely statistical approaches are naive. I suspect they have an agenda.”

The Koch donation, to many, confirms those suspicions. “Why would a scientist accept funding from an organization with no interest in advancing the science?” asked Benjamin Santer, an atmospheric scientist at Lawrence Livermore National Laboratory….

Peter Thorne, a leading expert on temperature data at the National Oceanic and Atmospheric Administration’s National Climatic Data Center in Asheville, N.C., said … he was unsurprised by the Berkeley project’s focus on temperature data. “For those who wish to discredit the science, this record is the holy grail,” he said. “They figure if they can discredit this, then society would have significant doubts about all of climate science.”

But temperature is only one indicator of global warming, Thorne said. “Even if the thermometer had never been invented, the evidence is there from deep ocean changes, from receding glaciers, from rising sea levels and receding sea ice and spring snow cover. All the physical indicators are consistent with a warming world.

“There is no doubt the trend of temperature is upwards since the early 20th century. And that trend is accelerating.”