Hockey-Stick Researcher Exonerated in Penn State Investigation

The research of Michael Mann, who in 1999 published the “hockey stick” diagram illustrating the apparent effect of human activity on climate change, has consistently been a target of climate change skeptics. They have accused Mann of manipulating data, destroying records, and restricting progress in studying global warming.

Pennsylvania State University, where he is based, recently concluded a 7-month investigation of his research practices, spurred by newer accusations arising from emails stolen from the University of East Anglia in Fall 2009. In its final report, the investigative committee unanimously found that the accusations against Mann’s research practices were without merit.

Climate Progress, a climate-science blog, summarizes the history of accusations against Mann by critics ranging from Newsweek, CBS, and the Wall Street Journal to scientists at the Massachusetts Institute of Technology and Woods Hole Oceanographic Institute.  University investigation notwithstanding, perhaps the greatest evidence in support of Mann’s research is the abundance of independent research among multiple lines of evidence that supports his findings. But if that hasn’t quieted the skeptics, it is unlikely this new report will either.