Fires in Borneo

Smoke from forest fires can prevent clouds from forming raindrops. Sootparticles in the smoke cause many small water droplets to condense, preventingthe buildup of large droplets. Small droplets remain suspended in theatmosphere instead of falling as rain.

The image above, taken over the Indonesian island of Borneo,illustrates this phenomenon from two instruments aboardthe Tropical Rainfall Measuring Mission (TRMM). The Visible and InfraredSensor (VIRS) detects fires and shows the extent of clouds and smoke, whilethe Precipitation Radar (PR) detects cloud water droplet size and rainfall.

Smoke from the fires (red dots) in the upper right combined with clouds inthe center of the image. TRMM's precipitation radar showed the smallsize (darker teal) of the water droplets suspended in these clouds comparedto the larger (brighter teal) droplets in the clean clouds to the left.Only the cleanclouds produced significant rainfall (blue).

Learn more about the effects of particles on clouds inEvery Cloud had a Filthy Lining.
And the Tropical Rainfall Measuring Mission in the TRMM Fact Sheet

References & Resources

Image by Greg Shirah, NASA Goddard Space Flight Center Scientific Visualization Studio