Is James Hansen a climate prophet?

Everything changed after his 1988 congressional testimony.

For decades, the average temperature in the United States and the Arctic Sea-Ice volume remained relatively stable, despite the increase of atmospheric CO2 from ~300 ppm in 1920 to ~350 ppm in 1988. And then something remarkable happened. Following Dr. James Hansen's groundbreaking testimony before Congress, the US experienced a sudden and dramatic temp…