Sunday, February 08, 2015

Why the Long Paws?

A favorite resort of those who style themselves climate skeptics is to claim that global warming has "paused" for the past 17 years. This claim rests on a slender but not quite nonexistent base of empirical support - the fact that if one looks only at the satellite upper troposphere data, 1998 is still the warmest year on record. The reason for this is understood. Upper troposphere temperatures are significantly more sensitive to El Niño conditions than those at the surface, and 1998 was the last strong El Niño year. Consequently, the satellite temperature record shows larger year to year swings than the surface record.

Nevertheless, BOTH kinds of records, surface and satellite, show the same trend line of consistent increase on the decadal time scale. Details can be found at carbonbrief here. Carbonbrief also provides this interactive graph with NOAA, NASA, CRU, and the satellite RSS and UHA analyses of the temperature record. Interactive features include the ability to toggle individual curves on and off by clicking on the legend.