January 27, 2009
2008 was the coolest year since 2000 but still ranks in the top 10 warmest since 1880
The agency's Goddard Institute for Space Studies (GISS) released a map showing global temperature anomalies in 2008 compared to the 1950-1980 baseline period. The regions with the greatest warming included Eastern Europe, Russia, the Arctic, and the Antarctic Peninsula. Large areas of the central and eastern Pacific Ocean were cooler than the long-term average, a result of a La Niña event that began in 2007. Relative coolness is expected to continue into early 2009 but the researchers predict that a new global temperature record will be set in the next 1-2 years.
The map above shows global temperature anomalies in 2008 compared to the 1950-1980 baseline period. Below-average temperatures are shown in blue, average temperatures are white, and above-average temperatures are red. (Gray indicates no data.)
GISS also released a graph showing the long-term trend in surface temperatures since 1880.
The graph shows the long-term trend in surface temperatures since 1880. The annual average temperatures are shown in light orange, and the jaggedness of the line indicates how much the average global surface temperature varies from year to year. Because climate is so variable form year to year, it can be easier to spot long-term trends through multi-year averages. The dark red line shows the five-year running average, which is an average of five years of annual temperatures centered on a given year. Even this five-year average shows that climate has ups and downs, but the long-term increase in global average surface temperatures is obvious. The gray "barbells" indicate the range of uncertainty. Not surprisingly, the uncertainty is larger for older measurements than for more recent ones.
CITATION: NASA Earth Observatory - 2008 Global Temperature; NASA Goddard Institute for Space Studies - Global Temperature Trends: 2008 Annual Summation