'Pyrocumulus': Images show 'fire clouds' form over Oregon
EUGENE, Ore. - The stunning photographs of F-15s against the backdrop of a billowing eruption of forest fire smoke are very real - and very educational.
The photos help illustrate "pyrocumulus clouds," also known as "fire clouds," NASA said.
"Pyrocumulus clouds are similar to cumulus clouds, but the heat that forces the air to rise comes from fire instead of sun-warmed ground," the space agency explains. "Under certain circumstances, pyrocumulus clouds can produce full-fledged thunderstorms, making them pyrocumulonimbus clouds."
The F-15 photos captured July 31 by Jim Haseltine of the Oregon Air National Guard show clouds forming over the Oregon Gulch Fire, part of the Beaver Complex burning in Oregon and California.
NASA captured images of similar pyrocumulus cloud formation on August 2 with images from two earth-orbiting satellites.
The first was taken at 11 a.m.; the second around 1 p.m.
"The pair of natural-color images documents the evolution and rapid expansion of the fires," NASA said. "Many areas of active burning expanded significantly between the satellite overpasses, as smoke plumes blossomed into towering pyrocumulus clouds. The change was most dramatic over the Beaver Complex fire along the border of California and Oregon."
NASA said scientists monitor pyrocumulus clouds closely because they can inject smoke and pollutants high into the atmosphere. As pollutants are dispersed by wind, they can affect air quality over a broad area.
In the case of the Beaver Complex, the outburst of pyrocumulus activity lofted a large amount of smoke high into the atmosphere, NASA said. Winds pushed the north and east over Oregon, coloring the skies over Eugene a hazy shade of orange.
On Sunday, August 3, the Ozone Mapping Profiler Suite (OMPS) on the Suomi NPP satellite detected the smoke as it passed over Oregon and drifted toward Idaho and Montana, NASA said.