Volcanic Suppression: Major eruptions can reduce sea level

Large volcanic eruptions can temporarily cool Earth’s climate and, a team of scientists now suggests, lower sea level worldwide.

BLOWING ITS TOP. Ocean cooling following the June 1991 eruption of Mount Pinatubo in the Philippines caused sea level worldwide to temporarily drop about 5 millimeters. D. Harlow/U.S. Geological Survey

The tiny particles of broken rock and droplets of condensed gases that a volcano ejects high into the atmosphere reflect sunlight into space.