Preliminary results from a controversial study of global temperature data confirm the overall warming trend long reported by government scientists in the United States and the United Kingdom, the study's director told a House panel today. The warming trend detected by scientists involved in the Berkeley Earth Surface Temperature Study -- a rise of 0.7 degree Celsius since 1957 -- "is very similar" to the findings of independent analyses by NASA, the National Oceanic and Atmospheric Administration and the U.K. Hadley Centre, study Chairman Richard Muller said.

"The world temperature data has sufficient integrity to be used to determine temperature trends," said Muller, a physicist at Lawrence Berkeley National Laboratory.