Russian Firestorm: Finding a Fire Cloud from Space Thick,
choking smoke hung over Russia on August 1, 2010, adding to the
misery of a stifling summer heat wave. Thousands of people were
fleeing nearly 700 fires burning in the drought-dried forests
and peat bogs of western Russia, while those not directly
threatened were struggling to see through and breathe the smoky
air. It was perhaps not too surprising, then, when the Ozone
Monitoring Instrument (OMI) on NASA’s Aura satellite recorded
high concentrations of aerosols over far northern Russia on
August 1. Smoke from forest fires contains tiny particles
(aerosols) produced when a fire incompletely burns through trees
and other carbon-based fuel. These aerosols usually linger in
the lower part of the atmosphere before falling out. On this
day, OMI measured aerosols above the top of high clouds. A
decade ago, a scientist trying to trace the source of those
aerosols would have looked for an erupting volcano. A volcanic
eruption, it was thought, was the only forc