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Red All Over

Rebecca Sloan Slotnick

The Bush Administration's decision to abandon the Kyoto Protocol may have left many people "seeing red"—literally. Scientists who study global climate change sometimes show areas of more rapid warming in red, as in the map above.

James Hansen and Marc Imhoff, with NASA's Goddard Institute for Space Studies and Goddard Space Flight Center, respectively, analyzed data from over 7,000 weather stations, taking special care to minimize what they call "heat-island" effects in urban areas. Asphalt roads, paved walkways and tar roofs absorb heat, keeping urban areas warmer than neighboring rural spots and resulting in locally elevated temperature readings. Hansen and Imhoff used rural station readings to adjust the urban records, hoping to reduce local effects, and plotted their data.

The map illustrates changes in the Earth's surface air temperatures from the year 2000 relative to the global mean temperature from 1951 to 1980. Negative changes in degrees Celsius (shades of blue) indicate cooling, whereas positive values (yellows and reds) designate areas of warming. The biggest warming took place not in spots that one would normally color red for "hot"—but rather in the Eurasian Arctic, northern Europe and Alaska. The contiguous United States experienced a slight increase in temperature, restoring temperatures to 1930s levels. On average, air temperature around the globe warmed 1 degree Fahrenheit (or 0.6 degrees Celsius) over the course of the past century.

Whether these results confirm or refute environmental policy decisions is a matter for debate. What is clear is the complexity of the global climate, and the importance of continued research. To learn more about global climate change, go to

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