Investigators at the National Science Foundation have exonerated climate scientist Michael E. Mann of allegations of research misconduct, Mann’s employer, Pennsylvania State University, said in an Aug. 23 statement.
Mann, director of Penn State’s Earth System Science Center, has been a target of climate-change skeptics. The developer of the once-contested “hockey stick” graph of temperature fluctuations over the past millennium, Mann is one of the scientists whose e-mail messages were hacked from the University of East Anglia, in England, and made public in late 2009. Critics cite these e-mails, some of them controversial, as evidence that Mann manipulated data.
“No direct evidence has been presented that indicates the Subject [Mann] fabricated the raw data he used for his research or falsified his results,” reads the NSF Inspector General’s report, which is available on the agency’s website.
Mann’s statistical methods are still being scrutinized, the report says, but this scientific debate doesn’t constitute evidence of research misconduct.
“The various smears that have been manufactured by climate-change deniers about me and other climate scientists have no basis in reality,” Mann tells C&EN.
The NSF probe followed a Penn State investigation that cleared Mann of misconduct last year.
The NSF report “clearly exonerates professor Mann from any professional improprieties in his research, and adds credibility to the university’s own process of inquiry,” says Henry C. Foley, Penn State vice president for research.