High Quality Content by WIKIPEDIA articles! Michael E. Mann (born December 28, 1965) is an American physicist and climatologist, currently director of the Earth System Science Center at Pennsylvania State University. He is best known as lead author of a number of articles on paleoclimatology and as one of the originators of a graph of temperature trends over the last thousand years, called the "hockey stick graph" because of its shape. The graph was highlighted in an Intergovernmental Panel on Climate Change (IPCC) report, receiving both praise and criticism, and has been the subject of a long-running controversy. Mann is also known as a founding member of the RealClimate blog, to which he and a number of other scientists contribute, and is the co-author with Lee R. Kump of Dire Predictions: Understanding Global Warming (2008).