Monitoring Volcanic Gases: The Driving Force of Eruptions

Pictured above: Gas-monitoring instruments secured inside aircraft.

A primary objective in gas monitoring is to determine changes in the release of certain gases from a volcano, chiefly carbon dioxide (CO2) and sulfur dioxide (SO2). Such changes can be used with other monitoring information to provide eruption warnings and to improve our understanding of how volcanoes work. In recent years, we have directed increased attention toward volcanic gas emissions because of the newly appreciated hazards they sometimes pose and their effects on the Earth's atmosphere and climate.

Pictured above: Airborne gas monitoring: Flying beneath a volcanic gas plume to measure SO2 and CO2.

Pictured above: A volcanic eruption cloud.

Volcanic Air Pollution-A Health Hazard in Hawai`i

Noxious sulfur dioxide gas and other pollutants emitted from Kilauea Volcano on the Island of Hawai`i react with oxygen and atmospheric moisture to produce volcanic smog (vog) and acid rain. Vog poses a health hazard by aggravating preexisting respiratory ailments, and acid rain damages crops and can leach lead into household water supplies.

Pictured above: A USGS scientist collecting gas samples from a fumarole on a volcano, Alaska.

Pictured above: A scientist in her laboratory: Analysis of gas samples, Hawaii Volcano Observatory.

The U.S. Geological Survey's Hawaiian Volcano Observatory is closely monitoring gas emissions from Kilauea and working with health professionals, National Park Service, and local officials to better understand volcanic air pollution and to enhance public awareness of this hazard.