The Goddard Institute for Space Studies (GISS), which is under the authority of NASA has released their December 2008 temperature data and also the full 2008 annual data.
First, here is their December global anomaly map....
I did not see any of the specific numbers for the month, but I will continue to look..
The year 2008.
The base period from 1951-1980 was used to determine the global temperature anomalies.
--2008 was the coolest year since 2000, which is supported by other methods. (+0.44).
--2008 was the 9th warmest year since records were kept back to 1880. When considering the
margin of uncertainty, GISS is confident that 2008 was somewhere between the 7th and 10th warmest year on record.
--The ten warmest years all occurred from 1997-2008.
GISS states that comparing the 2008 chart below left with the mean 2001-2007 anomalies clearly shows why 2008 was the coolest since 2000. The main differences between the two charts is in the Pacific. Note: the cooling in the Pacific during 2008 and also over North America.
GISS also responds to questions about their prediction from last year which stated that a new global temperature record was likely within the next 2-3 years (now, the next 1-2 years).
According to GISS, there are several factors to consider when making this prediction......
1. El Nino Southern Oscillation (ENSO). History says that a prolonged La Nina is unlikely for 2009/2010 despite the trends over the past few months. The subsurface of the Pacific in their opinion appears recharged for the next El Nino and there is a good chance for an El Nino in 2009 or 2010. Note; There is usually a 3-6 month lag in global temperature response to a change in ENSo conditions.
2. Solar Irradiance. Most solar physicists expect the irradiance to begin to pick up in the next several months after a longer than normal period of low solar output. Even if the irradiance does pick up, the 1-2 year lag in any surface temperature response to the cycle means that solar irradiance will continue to provide a negative anomaly for the next 2-3 years.
3. Volcanic aerosols.
4. Greenhouse gases (GHG's). The latest GHG forcing trend translates into a mean warming rate of ~0.15 Celsius per decade.
Updated prediction from GISS.......It still seems likely that a new global temperature record will be set within the next 1-2 years, despite the moderate negative effect of the reduced solar irradiance.
Thanks to global-warming.accuweather