Patagonian Ice Sheet at the Last Glacial Maximum. Map of South America showing the extent of the Patagonian Ice Sheet at the LGM (after ). Modern oceanographic conditions around South America are also indicated. Dashed lines indicate mean annual sea surface temperatures (after ). Arrows show directions of major surface currents, the Antarctic Circumpolar Current (ACC), the Humboldt Current (HC), the Cape Horn Current (CHC) and the Malvinas Current (MC) (after ).