NASA MODIS Image of the Day: September 18, 2011 – Pyrocumulonimbus plume from fires in Minnesota (afternoon overpass)
On August 18, 2011, a lightning strike in the Boundary Waters Canoe Area Wilderness region of northeastern Minnesota sparked a forest fire.
On September 12, the Incident Information System reported that the Pagami Creek Fire “made an unprecedented 16-mile run to the east, reaching the edge of Polly Lake.
The fire became a plume-driven event and reached in excess of 60,000 acres.” The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Aqua satellite captured this image at 1:50 p.m. Central Daylight Time. Red outlines show where MODIS detected areas of high surface temperatures associated with active burning. In this image, a cauliflower-textured plume rises well above the gray-beige smoke plume that blows toward the north-northeast. The cloudy plume has fanned out to the east and northeast, thick enough to completely hide the land and water surfaces below. Large fires can do more than scorch vegetation and clog the skies with smoke. They can actually create their own weather. By heating the air overhead, fires push the warmed air upward. Mixed with smoke, the air rises high enough for its water vapor to condense and form clouds. If the air rises fast enough, the water vapor forms ice crystals that charge the cloud with electricity, and lightning often results. These fire-provoked thunderstorm clouds are known as pyrocumulonimbus clouds. Minnesota Public Radio reported that the plume from the Pagami Creek Fire was picked up by Doppler radar. The extreme behavior of the fire prompted evacuations in the region, the Incident Information System reported. On September 16, the fire was only 8% contained, although significant progress was made during the day on one section of the fire. There were 436 firefighters working the fire on that date, along with seven helicopters and eight fixed-winged airplanes.
