2006 Warmest Year on Record for Lower 48

The U.S. National Oceanic and Atmospheric Administration (NOAA) has reported that 2006 was the warmest year on record for the 48 contiguous states and the fifth warmest on record globally. The annual average temperature in the U.S. was 55ºF (13ºC), 2.2ºF (1.2ºC) above the 20th century mean and 0.07ºF (0.04ºC) warmer than 1998, the next warmest year on record. According to NOAA, an unusually warm December was partially responsible for the record, with five states reporting the warmest December since recordkeeping began in 1895. Explaining the warming, NOAA pointed to a combination of oceanic and atmospheric disruptions in the tropical Pacific (known as El Niño) and a “long-term warming trend, which has been linked to increases in greenhouse gases.” That attribution of warmer than average temperatures to global warming breaks a trend in recent NOAA reports, which have tended to point solely to El Niño events or other short-term causes of warming. Climate reports from 1998 through 2006 are available online at www.ncdc.noaa.gov (click on “Monitoring” under the heading “Climate Info”).