Michael E. Mann: 2014 Was Earth’s Warmest Year on Record

by Dr. Michael E. Mann, facebook, January 16, 2015

Three major climate organizations (JMA, NASA, and NOAA) have now released their official estimates for the 2014 Global Mean Surface Temperature. Both JMA and NOAA conclude that 2014 was substantially higher, i.e., outside the margin of error, of previous contenders (1998, 2005, and 2010) while NASA finds 2014 to be warmest, but within the margin of error of 2005 and 2010 (i.e., a “statistical tie”).

Based on the collective reports, it is therefore fair to declare 2014 the warmest year on record. This is significant for a number of reasons. Unlike past record years, 2014 broke the record without the "assist" of a large El Niño event. There was only the weakest semblance of an El Niño, and tropical Pacific warmth contributed only moderately to the record 2014 global temperatures. Viewed in context, the record temperatures underscore the undeniable fact that we are witnessing, before our eyes, the effects of human-caused climate change. It is exceptionally unlikely that we would be seeing a record year, during a record warm decade, during a multidecadal period of warmth that appears to be unrivaled over at least the past millennium, were it not for the rising levels of planet-warming gases produced by fossil-fuel burning.

The record temperatures *should* put to rest the absurd notion of a “pause" (what I refer to as the “Faux Pause” in Scientific American: http://www.scientificamerican.com/article/earth-will-cross-the-climate-danger-threshold-by-2036/) in global warming. There is a solid body of research now showing that any apparent slow-down of warming during the past decade was likely due to natural short-term factors (like small changes in solar output and volcanic activity) and internal fluctuations related to, for example, the El Nino phenomenon. The record 2014 temperatures underscore the fact that global warming and associated climate changes continue unabated as we continue to raise the concentrations of greenhouse gases in the atmosphere.