global change” Terra Nova 14, 129-155 Snowball Earth (2005) Rita Chang & Alan Fine OCLC 165116212 References External links Short Hoffman bio Snowball Earth Theory Snowball Earth web site Geological Association of Canada Medals and Awards Miller Medal Royal Society of Canada 1941 births Living people Canadian geologists Geological Survey of Canada personnel Fellows of the Royal Society of Canada Harvard University faculty Johns Hopkins University alumni Foreign associates of the National Academy of Sciences McMaster University alumni People from Toronto Logan Medal recipients Wollaston Medal winners Officers of the Order of Canada Penrose Medal winners