U.S. Average Temperature (up to 2000) According to James Hansen

Hansen et al 1999 [http://pubs.giss.nasa.gov/docs/1999/1999_Hansen_etal.pdf ]:

Hansen et al 2001 [http://pubs.giss.nasa.gov/docs/2001/2001_Hansen_etal.pdf ]:

Superimposing Hansen 2001 (red / blue) onto Hansen 1999 (black), and highlighting some of the significant changes: