Fire clouds have been recorded rising from wildfires currently devastating large tracts of land in California. Over 100,000 acres of land across the state have experienced wildfires this year.
Around 80 percent of the Golden State is currently experiencing drought conditions. So far, this year has not provided great relief to a state still suffering from last year, which was the driest in 119 years. Vast quantities of dried vegetation in woodland areas became a tinderbox, ready to come ablaze in an instant. Lightning strikes at the beginning of August set off the dried timber, causing wildfires to break out in many areas across the state.
Winds blowing over wildfires can cause flames to rise into the air, in tall pillars called pyrocumulus clouds, commonly known as fire clouds. These features are quickly lifted to great altitudes by the rising of heated air, driven by the fire. As heated air is driven into the air, it collides with cooler air, and water vapor in the atmosphere forms into a cloud, in a similar fashion to the production of fair-weather cumulus clouds. The more common process is driven by heat rising from the ground.
A pilot aboard an F-15C fighter jet , flying for the Oregon Air National Guard on 31 July, took photographs of the fire clouds, as they roared into the sky above the inferno. The fire clouds pictured in these images were rising from the Beaver Complex fire, located on the Oregon/California border.
Smoke and pollutants can rise high into the air, where they can be carried great distances by upper-level winds, before falling back to Earth. Particles from the Beaver Complex fire drifted across Oregon, toward Montana and Idaho.
Satellite images show these fire clouds looking like pieces of white-colored broccoli, with a dark stalk and a lighter-colored head. These images reveal information about the nature of the wildfires, as well as how the wildfires have changed over time.
Terra and Aqua, a pair of Earth-monitoring satellites, have already taken stunning views of the Beaver Complex fire. This is one of the most-developed fire clouds ever recorded by the terrestrial observatories. Observations of the pyrocumulus clouds was also undertaken with the highly-advanced MODIS heat sensor aboard Aqua. This instrument detects 36 bands of electromagnetic wavelengths.
"There have been a few other occasions when Aqua or even Terra captured mature pyrocumulus clouds, and it is always a godsend scientifically because of all the wavelengths that MODIS offers for analysis," Mike Fromm, meteorologist with the Naval Research Laboratory, said.
Fire tornadoes are another phenomenon that can also be created by high winds during wildfires.
Pyrocumulus clouds can also transform into pyrocumulonimbus clouds, which are the source of all thunderstorms. Ironically, by undergoing this transformation, fire clouds can create massive downpours of rain.
