What effect did the explosion at Mt. St. Helens have on global climate? Where can I find more information on this?

Hartf

Hi Hartf,

There was little effect on global climate by the Mt. St. Helens 1980 eruption. There were two main reasons for this. The first is that the eruption plume was high enough to get into the stratosphere only for the first 0.5 to 1 hour of the eruption; for the rest of the day it was completely within the troposphere. Ash and gases in the troposphere don't hang around long enough to affect the climate because they get washed out by rain and snow. The second reason is that there was very little sulfur in the erupting material at Mt. St. Helens. Since the 1982 El Chichon and 1991 Pinatubo eruptions, it has become clear that the major contribution to changing climate that is made by big eruptions is the production of sulfuric acid droplets (called aerosols). Sulfur dioxide gas is produced by the volcanoes and it reacts with water in the atmosphere to produce the aerosols. If there is little sulfur erupted (such as at Mt. St. Helens) there will be very few aerosols produced, and the climatic effects will be negligible.

Sincerely,

Scott Rowland

Other Categories        Other Questions
To VolcanoWorld