InsideClimate: Climate scientist Michael Mann has spent much of his career in the crosshairs of climate denialists. A professor of meteorology and director of the Earth System Science Center at Pennsylvania State University, Mann is best known for helping to develop the famous "hockey stick" graph, which reconstructed 1,000 years of global temperature data and showed the abrupt warming of the late 20th century. Mann, who studied theoretical physics before taking up climate research, published the paper explaining...