Satellite measured temperature anomalies of the lower troposphere were just slightly above normal globally and basically right at normal for the northern hemisphere, according to Remote Sensing Systems (RSS).
The December 2012 temperature anomaly image of the lower troposphere below shows that widespread cold covered much of central Asia last month, while a significant contrast in temperature anomalies existed from west to east across Canada. Note: Blues and purples indicate colder than normal conditions for the month, while reds and oranges show warmer than normal. Image courtesy of RSS.
Below is a chart from RSS showing the up to date temperature anomaly trend of the lower troposphere globally, which is currently at +0.131 C. per decade.
December 2012 global anomaly....... +.101 C.
December 2012 northern hemisphere anomaly...... +0.002 C.
December 2012 United States anomaly..... +0.83 C.
A conspicuous region of cooling in the northern Atlantic may be due to a reduction in the Atlantic Meridional Overturning Circulation (AMOC) over the twentieth century and especially between 1970 and 1990.
The 2014-15 December through February period was the 2nd warmest such period on record globally and for the Northern Hemisphere.
Latest status report on the northern and southern hemispheric sea ice extent.
Actual observations show that Arctic Sea ice has thinned considerably since the mid-1970's.
Up to date temperature, ice and snow data with trends
Both NOAA and NASA GISS have confirmed that the January 2015 combined global land/ocean surface temperature was the 2nd warmest on record.