Mt. St. Helens has little weather effect


  • Peter M. Bell


Despite the ash spewed into the atmosphere, Mount St. Helens had less effect on the weather than might have been anticipated. The ash from the eruption had no effect upon precipitation and had a lower nitrate content than particulates in air samples unaffected by the fallout, according to recent reports by NOAA.

A team led by Rudolf Pueschel of the Air Resources Laboratories measured airborne particles and cloud droplets upwind and downwind of the volcano in April 1980. Downwind, the mass of particles in the air was thousands of times greater, but the ash appeared to have no effect on the amount of water in clouds or the size of water droplets.