WASHINGTON (AP) -- Last year was the warmest on record for the United States, with readings pushed over higher than normal by the unusual and unseasonably warm weather during the last half of December.
Preliminary data from the National Climatic Data Center listed the average temperature for the 48 contiguous states last year as 55 degrees Fahrenheit. That's 2.2 degrees warmer than average and 0.07 degree warmer than 1998, the previous warmest year on record.
Worldwide, the agency said, it was the sixth warmest year on record.
In December the Center had predicted that 2006 would be the United States' third warmest year, but unusual readings later that month pushed the year into first place.
The Center said it is not clear how much of the warming is a result of greenhouse-gas induced climate change and how much resulted from the current El Nino warming of the tropical Pacific Ocean.
http://www.breitbart.com/news/2007/01/09/D8MHUMVO0.html