5 01 2010
December 2009 UAH Global Temperature Update +0.28 Deg. C
by Roy W. Spencer, Ph. D.
The global-average lower tropospheric temperature anomaly fell back to the October level of +0.28 deg. C in December.
The tropics continue warm from El Nino conditions there, while the NH and SH extratropics anomalies cooled from last month. While the large amount of year-to-year variability in global temperatures seen in the above plot makes it difficult to provide meaningful statements about long-term temperature trends in the context of global warming, the running 25-month average suggests there has been no net warming in the last 11 years or so.
[NOTE: These satellite measurements are not calibrated to surface thermometer data in any way, but instead use on-board redundant precision platinum resistance thermometers carried on the satellite radiometers.]