Global Climate Trend Since Nov. 16, 1978: +0.14 C Per Decade

Global composite temp.: +0.10 C (about 0.18 degrees Fahrenheit) above 30-year average for April.

Northern Hemisphere: +0.12 C (about 0.22 degrees Fahrenheit) above 30-year average for April.

Southern Hemisphere: +0.09 C (about 0.16 degrees Fahrenheit) above 30-year average for April.

Tropics: +0.17 C (about 0.31 degrees Fahrenheit) above 30-year average for April.

March temperatures (revised):

Global Composite: +0.18 C above 30-year average

Northern Hemisphere: +0.33 C above 30-year average

Southern Hemisphere: +0.04 C above 30-year average

Tropics: +0.23 C above 30-year average

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

Notes on data released May 6, 2013:

Compared to seasonal norms, during April the coldest area on the globe was in the southeastern portion of Saskatchewan, Canada, where the average temperature was as much as 4.82 C (about 8.7 degrees Fahrenheit) cooler than seasonal norms. Compared to seasonal norms, the “warmest” area on the globe in April was on the northeastern Russian coast near the Bering Sea. Temperatures there averaged 4.51 C (about 8.1 degrees Fahrenheit) warmer than seasonal norms for April.

Archived color maps of local temperature anomalies are available on-line at:
http://nsstc.uah.edu/climate/
The processed temperature data is available on-line at:
vortex.nsstc.uah.edu/data/msu/t2lt/uahncdc.lt
As part of an ongoing joint project between UAHuntsville, NOAA and NASA, John Christy, a professor of atmospheric science and director of the Earth System Science Center (ESSC) at The University of Alabama in Huntsville, and Dr. Roy Spencer, an ESSC principal scientist, use data gathered by advanced microwave sounding units on 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.

Neither Christy nor Spencer receives any research support or funding from oil, coal or industrial companies or organizations, or from any private or special interest groups. All of their climate research funding comes from federal and state grants or contracts.