Prior to the year 2000, the two hottest years in the GISS US record were 1934 and 1921 respectively. 1998 was the third hottest year, and more than half a degree cooler than 1934.
This of course made no sense to Hansen, because CO2 has increased a lot since the 1930s. Einstein once said “If the facts don’t fit the theory, change the facts.”
Hansen apparently took him literally.