National Geographic : 1992 Feb
A 1950s workhorse, NCAR's Lockheed Electra has traveled worldwide to study air quality and weather systems. For its Persian Gulf assignment, the four-engine turboprop carried 19 researchers and crew. Close to the fires, instru ments found high concentra tions of soot and oil droplets (inset at far left) creating an oily drizzle that stretched more than 60 miles downwind. Remaining aloft were soot particles that had formed clusters (inset at left). Floating like feathers on air warmed by the sur face below, they were carried for hundreds of miles downwind before falling or being washed out by rain. Differences in air tempera ture stratified the plume into distinc Y LLOYDK. TOWNSEND tive layers.