Keywords: Global cooling.jpg Figure A 6 from the 1975 NAS report understanding climatic change A program for action Northern hemisphere surface temperature from 1880 to 1968 Data from Budyko 1968 updated by Asakura after 1959 indicated by dashed line on graph http //upload wikimedia org/wikipedia/en/b/bd/DSCN4904-nas-a 6_crop jpg 1975 NAS public domain PD-USGov Global cooling Charts |