1225 - Ice Sheets

Data adapted from 'The Laurentide and Innuitian ice sheets during the Last Glacial Maximum' by A.S. Dyke et. al., which was way better than the sequels 'The Laurentide and Innuitian ice sheets during the Last Glacial Maximum: The Meltdown' and 'The Laurentide and Innuitian ice sheets during the Last Glacial Maximum: Continental Drift'.

This is an archival copy of the works from xkcd.com.