In Montana, Fires Follow Drought
In Montana, wildfires rage nearly every year, but the forests are particularly susceptible to burning during years that are hot. The arid climate dries out the forests, making it easier to ignite and burn.
Images from satellites can help scientists identify where wildfires are burning. They can also measure the "greenness" of the land, which represents how abundant plant growth is on the ground. Images from NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) capture this greenness, and every week the Wildland Fire Assessment System analyzes the conditions. This constant monitoring provides useful indicators of what the wildfire risk is from region to region. When the image is brown or red, it means the ecosystem is very dry. On the other hand, green on the land means there is more lush vegetation and plant growth.
More fires are expected in Montana when the MODIS images are redder and browner than average during the fire season. In the above graphic, the greenness images were taken during the weeks of June 24, 2003 and June 28, 2005; these weeks occurred early in the fire season, when many wildfires were just beginning.