In terms of exactly how long the “Pause” has lasted, it depends on the data set and what it is being measured, e.g. in Werner Brozek’s recent article Statistical Significances – How Long Is “The Pause”? he showed that;
1. For GISS, the slope is flat since September 1, 2001 or 12 years, 1 month. (goes to September 30, 2013) 2. For Hadcrut3, the slope is flat since May 1997 or 16 years, 5 months. (goes to September) 3. For a combination of GISS, Hadcrut3, UAH and RSS, the slope is flat since December 2000 or 12 years, 10 months. (goes to September) 4. For Hadcrut4, the slope is flat since December 2000 or 12 years, 10 months. (goes to September) 5. For Hadsst3, the slope is flat since November 2000 or 12 years, 11 months. (goes to September) 6. For UAH, the slope is flat since January 2005 or 8 years, 9 months. (goes to September using version 5.5) 7. For RSS, the slope is flat since November 1996 or 17 years (goes to October)