First Five Months of 2010 Second Warmest on Record

Global Temperature Report: May 2010

First five months of 2010 second warmest on record

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

May temperatures (preliminary)

Global composite temp.: +0.53 C (about 0.95 degrees Fahrenheit) above20-year average for May.

Northern Hemisphere: +0.78 C (about 1.40 degrees Fahrenheit) above 20-yearaverage for May.

Southern Hemisphere: +0.29 C (about 0.52 degrees Fahrenheit) above 20-yearaverage for April.

Tropics: +0.71 C (about 1.28 degrees Fahrenheit) above 20-year average forMay.

April temperatures (revised):

Global Composite: +0.50 C above 20-year average

Northern Hemisphere: +0.80 C above 20-year average

Southern Hemisphere: +0.20 C above 20-year average

Tropics: +63 C above 20-year average

(All temperature anomalies are based on a 20-year average (1979-1998) forthe month reported.)

Notes on data released June 7, 2010:

In the race to become the warmest year in the satellite temperature record, 2010 is running a close second to 1998 but might begin to falter as the El Ninåo Pacific Ocean warming event continues to fade, according to Dr. John Christy, professor of atmospheric science and director of the Earth System Science Center at The University of Alabama in Huntsville.

Through the first 151 days of the year (Jan. 1 through May 31), 2010 has averaged 0.59 C warmer than season norms. Global average temperatures through the first five months of 1998 were 0.65 C warmer than normal.

The chance that 2010 will set a record drops as the El Nino warming event fades and the Central Pacific Ocean cools. NOAA has issued a "watch" for a La Nina Pacific Ocean cooling event.

For the third time in the past four months a new high temperature has been set for the Arctic. Temperatures in the Arctic -- latitude 60 N (about even with Helsinki and the southern tip of Greenland) to the North Pole -- were a full two and a half degrees Celsius (about 4.5 degrees Fahrenheit) warmer than seasonal norms for that region.

May 2010 set records as the warmest May in the 32-year satellite temperature record for both the Northern Hemisphere (+0.78 C) and the northern temperate zone, also +0.78 C.

Compared to the other 31 Mays in the record, May 2010 was the second warmest May globally (+0.53 C), and in the tropics (+0.81 C); fourth warmest May in the Southern Hemisphere (+0.29 C); and seventh coolest May in both the Southern Polar region (-0.86 C) and the continental U.S., where the average temperature was 0.47 C cooler than seasonal norms.

January through May ComparisonAverage Global Anomaly (Celsius) 1998 2010NH +0.76 +0.80SH +0.55 +0.37TR +1.07 +0.71

Global Temperature Anomalies Year Mo 1. 1998 4 +0.76 2. 1998 2 +0.76 3. 2010* 3 +0.66 4. 1998 5 +0.65 5. 2010* 1 +0.64 6. 2010* 2 +0.61 7. 1998 1 +0.58 8. 1998 6 +0.57 9.*2010* 5 +0.5410. 1998 3 +0.5311. 1998 7 +0.5212. 1998 8 +0.5213. 2007 1 +0.5114. 2010* 4 +0.515. 2009 9 +0.516. 2009 11 +0.517. 2005 10 +0.4718. 2005 4 +0.4619. 2003 12 +0.4520. 1998 9 +0.45

Temperature Anomalies in the Tropics Year Mo 1. 1998 2 +1.3 2. 1998 1 +1.09 3. 1998 4 +1.06 4. 1998 3 +1.05 5. 1998 5 +0.89 6. 2010* 2 +0.81 7. 2010* 3 +0.73 8. 1997 12 +0.73 9.*2010* 5 +0.7210. 2010* 1 +0.6611. 2010* 4 +0.6512. 1987 12 +0.62

Arctic Temperature Anomalies Year Mo 1.*2010 5 +2.51 2. 2010* 4 +2.45 3. 2010* 2 +2.3 4. 2007 4 +2.27 5. 1995 4 +2.26 6. 2006 2 +2.24 7. 2009 12 +2.09 8. 2005 12 +2.06 9. 1996 11 +2.0110. 2001 12 +1.9411. 2003 10 +1.8312. 2005 4 +1.8113. 2005 11 +1.814. 2010* 1 +1.7915. 2002 10 +1.7316. 1981 1 +1.7217. 2005 5 +1.7218. 2010* 3 +1.7219. 1980 2 +1.7220. 2002 11 +1.72

As part of an ongoing joint project between UAHuntsville, NOAA and NASA, Christy and Dr. Roy Spencer, a principal research scientist in the ESSC, 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