A climatologist can advance claims that the National Review defamed him by likening him to convicted child molester Jerry Sandusky and accusing him of academic fraud, a judge ruled.

Michael Mann is a meteorology professor at Penn State University, which was rocked by Sandusky's sex abuse scandal in late 2011. In addition to running the university's Earth System Science Center, Mann co-wrote the "Hockey Stick Graph," a purported long-term analysis of global climate trends using indicators such as tree rings.

Questions over Mann's work arose in 2010 when emails between Mann and climate scientists at the University of East Anglia surfaced.