From the New York Times,
James E. Hansen, the climate scientist who issued the clearest warning of the 20th century about the dangers of global warming, will retire from NASA this week, giving himself more freedom to pursue political and legal efforts to limit greenhouse gases.
Here is how reality stacks up against Dr. Hansen's famous forecast. His forecast is highlighted by the yellow arrow. The actual is highlighted by the gray arrow. Actual world temperatures are a full half degree Celsius (a huge difference) colder than he forecast. These are his own figures.