Great, simple, clear image. Kudos to the NASA Earth Observatory! Here’s the caption:

“This image, created from data collected by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite from June 26 though July 3, 2007, shows land surface temperatures compared to average temperatures observed during the same period in 2000, 2001, and 2002. Deep red across the Southwest and the Intermountain West indicate that temperatures were much higher than they were in 2000-2002. The Southeast also experienced warmer temperatures. Northern California, Oregon, and Washington appear to be cooler than in previous years, as indicated by the blue tones. The heat wave started mid-way through the week-long period shown in this image. While temperatures may have soared at the end of the period, cooler temperatures earlier in the week dominate the signal.

“The Southern Plains are dark blue where temperatures were much cooler than they had been in previous years. During this period, torrential rains drenched the region, causing wide-spread flooding in Texas and Oklahoma and in Kansas and Missouri. The gray region over Kansas and Oklahoma is an area in which MODIS could not record the land’s temperature because of perpetual cloud cover during the week-long period.”

My only quibble is that “anomaly” might not be best phrase to communicate with broad audiences. “Variation from 2000-02 Average Temperature” maybe? Something like that?

The full-size, 4.8MB image shows the entire surface of the Earth, BTW. And the uniform grey oceans mean that you could easily add an alpha channel… Hmmm.