Atmosphere Contents

4. Energy Budgets

Two large volcanic eruptions in the last century have had an effect on climate

Volcanoes

Two large volcanic eruptions have occurred in the last century which are thought to have had an effect on climate: El Chichon, Mexico in April 1982; and Mount Pinatubo, Philippines, June 1991. Mount Pinatubo had the greatest effect on the Earth's climate and ejected 20 million tons of sulfur dioxide into the stratosphere. This was thought to be primarily responsible for a 0.8 degrees Celsius drop in global average air temperature in 1992 with global climatic effects peaking in late 1993. This connection was confirmed by satellite data which indicated that the sulfur dioxide from the eruption caused a percentage increase in the amount of sunlight reflected by the atmosphere back to space causing the surface of the Earth to cool.

What was the climatic effect of the eruption of Mount Pinatubo?