NASA maps global fires from the sky

Data will help study of how blazes affect climate

A fiery planet is seen in an image from NASA's Terra satellite.

GREENBELT, Maryland (CNN) -- Using instruments aboard a spacecraft named Terra, NASA scientists have generated a new set of maps showing the distribution of all the fires burning around the globe over the course of an entire year.

The purpose of the maps is to create a long-term record of fire activity around the Earth to help scientists better understand how fires impact the climate.

NASA's Terra satellite was launched in 1999, and its Moderate Resolution Imaging Spectroradiometer, called MODIS, has been monitoring the Earth for fires every day since February 2000. Its operators say its fire-sensing capabilities far surpass those of any other Earth-observing satellite. MODIS detected nearly a million fires from August 2001 to August 2002.

The new maps document the extreme fire season experienced this year in the United States. Though the large wildfires in the Western United States have garnered most of the media's attention, the new NASA maps also highlight the smaller but far more frequent blazes across the Southeast.

The maps also show dramatic fires across Siberia, Australia, Brazil and Africa. Many of the fires burning in those areas swept across savannah and grassland, with total acreage burned in a single fire far exceeding that of any U.S. wildfire.

But scientists caution that not all wildfires are created equal. While grassland fires can be huge, there's not much fuel on the open plain to burn. Forest fires such as those that have raged in the U.S. West are fed by tons of dead trees and other detritus that have accumulated on the forest floor over long periods of time.