Global climate trend since Nov. 16, 1978: +0.14 C per decade

January temperatures (preliminary)

Global composite temp.: -0.09 C (about 0.16 degrees Fahrenheit) below 30-year average for January.

Northern Hemisphere: -0.06 C (about 0.11 degrees Fahrenheit) below 30-year average for January.

Southern Hemisphere: -0.13 C (about 0.23 degrees Fahrenheit) below 30-year average for January.

Tropics: -0.13 C (about 0.23 degrees Fahrenheit) below 30-year average for January.

December temperatures (revised):

Global Composite: +0.13 C above 30-year average

Northern Hemisphere: +0.20 C above 30-year average

Southern Hemisphere: +0.06 C above 30-year average

Tropics: +0.04 C above 30-year average

(All temperature anomalies are based on a 30-year average (1981-2010) for the month reported.)

The University of Alabama in Huntsville scientists use data gathered by NOAA and NASA satellites to get accurate temperature readings for almost all regions of the Earth. This includes remote desert, ocean and rain forest areas where reliable climate data are not otherwise available.

The satellite-based instruments measure the temperature of the atmosphere from the surface up to an altitude of about eight kilometers above sea level. Once the monthly temperature data is collected and processed, it is placed in a “public” computer file for immediate access by atmospheric scientists in the U.S. and abroad.

Source: University of Alabama Huntsville