What gases are emitted by Kīlauea and other active volcanoes?
Ninety-nine percent of the gas molecules emitted during a volcanic eruption are water vapor (H2O), carbon dioxide (CO2), and sulfur dioxide (SO2). The remaining one percent is comprised of small amounts of hydrogen sulfide, carbon monoxide, hydrogen chloride, hydrogen fluoride, and other minor gas species.
Learn more at our website for Volcanic Gas.
Related Content
Does vog (volcanic smog) impact plants and animals?
Who monitors volcanic gases emitted by Kīlauea and how is it done??
Where and how do sulfur dioxide and volcanic gases (vog) affect air quality in Hawaii?
Should I cancel my plans to visit to Hawai`i Island because of sulfur dioxide (SO2) and vog?
What health hazards are posed by vog (volcanic smog)?
What is "vog"? How is it related to sulfur dioxide (SO2) emissions?
Does ash ever erupt from Kīlauea Volcano??
Why is it important to monitor volcanoes?
How are volcanic gases measured?
Is it dangerous to work on volcanoes? What precautions do scientists take?
Living with volcano hazards
Volcanic eruptions are among Earth’s most dramatic and powerful agents of change. Ash, mudflows, and lava flows can devastate communities near volcanoes and cause havoc in areas far downwind, downstream, and downslope. Even when a volcano is quiet, steep volcanic slopes can collapse to become landslides, and large rocks can be hurled by powerful...
Stovall, Wendy K.; Driedger, Carolyn L.; Westby, Elizabeth G.; Faust, Lisa M.
Volcanic air pollution hazards in Hawaii
Noxious sulfur dioxide gas and other air pollutants emitted from Kīlauea Volcano on the Island of Hawai‘i react with oxygen, atmospheric moisture, and sunlight to produce volcanic smog (vog) and acid rain. Vog can negatively affect human health and agriculture, and acid rain can contaminate household water supplies by leaching metals from building...
Elias, Tamar; Sutton, A. Jeff
One hundred volatile years of volcanic gas studies at the Hawaiian Volcano Observatory: Chapter 7 in Characteristics of Hawaiian volcanoes
The first volcanic gas studies in Hawai‘i, beginning in 1912, established that volatile emissions from Kīlauea Volcano contained mostly water vapor, in addition to carbon dioxide and sulfur dioxide. This straightforward discovery overturned a popular volatile theory of the day and, in the same action, helped affirm Thomas A. Jaggar, Jr....
Poland, Michael P.; Takahashi, T. Jane; Landowski, Claire M.; Sutton, A.J.; Elias, Tamar
Characteristics of Hawaiian volcanoes
Founded in 1912 at the edge of the caldera of Kīlauea Volcano, HVO was the vision of Thomas A. Jaggar, Jr., a geologist from the Massachusetts Institute of Technology, whose studies of natural disasters around the world had convinced him that systematic, continuous observations of seismic and volcanic activity were needed to better understand—and...
Poland, Michael P.; Takahashi, T. Jane; Landowski, Claire M.
The ongoing Puʻu ʻŌʻō eruption of Kīlauea Volcano, Hawaiʻi: 30 years of eruptive activity
The Puʻu ʻŌʻō eruption of Kīlauea Volcano is its longest rift-zone eruption in more than 500 years. Since the eruption began in 1983, lava flows have buried 48 square miles (125 square kilometers) of land and added about 500 acres (200 hectares) of new land to the Island of Hawaiʻi. The eruption not only challenges local communities, which must...
Orr, Tim R.; Heliker, Christina; Patrick, Matthew R.
Mauna Loa--history, hazards and risk of living with the world's largest volcano
Mauna Loa on the Island Hawaiʻi is the world’s largest volcano. People residing on its flanks face many hazards that come with living on or near an active volcano, including lava flows, explosive eruptions, volcanic smog, damaging earthquakes, and local tsunami (giant seawaves). The County of Hawaiʻi (Island of Hawaiʻi) is the...
Trusdell, Frank A.
Sulfur dioxide emission rates from Kilauea Volcano, Hawaii, 2007-2010
Kīlauea Volcano has one of the longest running volcanic sulfur dioxide (SO2) emission rate databases on record. Sulfur dioxide emission rates from Kīlauea Volcano were first measured by Stoiber and Malone (1975) and have been measured on a regular basis since 1979 (Elias and Sutton, 2007, and references within). Compilations of SO2...
Elias, T.; Sutton, A.J.
Kīlauea - An explosive volcano in Hawai‘i
Kīlauea Volcano on the Island of Hawai‘i, though best known for its frequent quiet eruptions of lava flows, has erupted explosively many times in its history - most recently in 2011. At least six such eruptions in the past 1,500 years sent ash into the jet stream, at the cruising altitudes for today's aircraft. The eruption of 1790...
Swanson, Donald A.; Fiske, Dick; Rose, Tim; Houghton, Bruce F.; Mastin, Larry
Emission of SO2, CO2, and H2S from Augustine Volcano, 2002-2008: Chapter 26 in The 2006 eruption of Augustine Volcano, Alaska
Airborne surveillance of gas emissions from Augustine Volcano and other Cook Inlet volcanoes began in 1990 to identify baseline emission levels during noneruptive conditions. Gas measurements at Augustine for SO2, CO2, and H2S showed essentially no evidence of anomalous degassing through spring 2005. Neither did a measurement on May 10, 2005,...
Power, John A.; Coombs, Michelle L.; Freymueller, Jeffrey T.; McGee, Kenneth A.; Doukas, Michael P.; McGimsey, Robert G.; Neal, Christina A.; Wessels, Rick L.
Carbon dioxide dangers demonstration model
Carbon dioxide is a dangerous volcanic gas. When carbon dioxide seeps from the ground, it normally mixes with the air and dissipates rapidly. However, because carbon dioxide gas is heavier than air, it can collect in snowbanks, depressions, and poorly ventilated enclosures posing a potential danger to people and other living things. In this...
Venezky, Dina; Wessells, Stephen
Invisible CO2 gas killing trees at Mammoth Mountain, California
Since 1980, scientists have monitored geologic unrest in Long Valley Caldera and at adjacent Mammoth Mountain, California. After a persistent swarm of earthquakes beneath Mammoth Mountain in 1989, geologists discovered that large volumes of carbon dioxide (CO2 ) gas were seeping from beneath this volcano. This gas is killing trees on the mountain...
Sorey, Michael L.; Farrar, Christopher D.; Gerlach, Terrance M.; McGee, Kenneth A.; Evans, William C.; Colvard, Elizabeth M.; Hill, David P.; Bailey, Roy A.; Rogie, John D.; Hendley, James W.; Stauffer, Peter H.
The National Volcano Early Warning System (NVEWS) will help USGS better monitor nation’s most dangerous volcanoes
In September 2004, USGS scientists detected sudden, but unmistakable, signs that Mount St. Helens was waking up. Volcano monitors had picked up the occurrence of hundreds of small earthquakes and other signals that the volcano’s crater floor had begun to rise. Within a week, several eruptions blasted clouds of ash into the atmosphere, and soon after, a new lava dome emerged in the crater.
Kīlauea Volcano Erupts
Today's update for June 21st, 2018 will be the last of the daily updates on this USGS feature story. We encourage you to keep checking the USGS Hawaiian Volcano Observatory (HVO) Kīlauea status website for daily activity updates. You can also visit the USGS Facebook page and the USGS Twitter feed as updates become available. For press inquiries, please email volcanomedia@usgs.gov.
EarthWord–Vog
Just like smog and fog, this EarthWord is not what you want to see while driving...
Living with Vog on an Active Volcano: New Resources
New informational products about the health hazards of volcanic air pollution known as “vog,” are available through a new interagency partnership.
EarthWord: Fumarole
Fumaroles are openings in the earth’s surface that emit steam and volcanic gases, such as sulfur dioxide and carbon dioxide. They can occur as holes, cracks, or fissures near active volcanoes or in areas where magma has risen into the earth’s crust without erupting. A fumarole can vent for centuries or quickly go extinct, depending on the longevity of its heat source.
New Study Looks at How People Cope with Vog
A new study to examine how people who live downwind of Kīlauea Volcano cope with volcanic gas emissions, or vog, is currently underway.
Kilauea’s Volcanic Gases and Their Environmental Impacts
U.S. Geological Survey Hawaiian Volcano Observatory scientists Jeff Sutton and Tamar Elias will update information on Kīlauea Volcano’s gas emissions and associated environmental impacts. Their presentation will be at the park’s Kīlauea Visitor Center Auditorium. Park entrance fees apply.
PubTalk 8/2018 — What on Earth is going on at Kilauea Volcano?
Title: What on Earth is going on at Kilauea Volcano?
- First significant summit explosions in nearly a century
- Largest summit collapse volume since at least 1800
- Voluminous fissure eruptions feeding channelized lava flow
- Unparalleled new opportunities for understanding the volcanic system
USGS HVO geochemist measuring gases released from Kīlauea Volcano
USGS Hawaiian Volcano Observatory geochemist measuring gases released from Kïlauea with a Fourier transform infrared (FTIR) spectrometer, an instrument that detects gas compositions on the basis of absorbed infrared light. The data obtained from FTIR measurements have been useful in identifying the many components of volcanic-gas emissions, which provide information on the
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Gas plume from Halemaʻumaʻu Crater, Kilauea Volcano
With stagnant winds present, the plume from Halema`uma`u Crater at the summit of Kilauea Volcano, stands straight up, showing off the distant, but bright, full moon.
Active lava lake at summit of Kīlauea volcano
Aerial photograph of active lava lake in Hale maʻumaʻu Crater at the summit of Kīlauea volcano.
Fumarole on Kīlauea Volcano, Hawaiʻi
Fumarole on Kīlauea Volcano, Hawaiʻi. Elemental sulfur vapor escaping from the fumarole has cooled to form yellow-colored crystals around its margins. Credit: Robert L. Christiansen.
Collecting Gas Sample at a Fumarole
USGS geologist Deborah Bergfeld collects a gas sample from a superheated (hotter than the boiling point) fumarole in Little Hot Springs Valley at Lassen Volcanic National Park.
Collecting Gas at a Boiling Pool
USGS geologist Laura Clor (right) and Rachel Teasdale (California State University – Chico, left) collect gas samples from a thermal feature at Sulphur Works in Lassen Volcanic National Park.
Monitoring Volcanic Gases on Kilauea's East Rift Zone II
Hawaiian Volcano Observatory Geochemist Jeff Sutton and CSAV international volcanology students visit a continuous gas monitoring site on Kilauea's east rift zone during field studies portion of the summer training course. Instrumentation at this site measures ambient concentration of noxious sulfur dioxide gas released from the volcano's vents, along with
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Monitoring Volcanic Gases on Kilauea's East Rift Zone
Hawaiian Volcano Observatory Geochemist Jeff Sutton and CSAV international volcanology students visit a continuous gas monitoring site on Kilauea's east rift zone during field studies portion of the summer training course. Instrumentation at this site measures ambient concentration of noxious sulfur dioxide gas released from the volcano's vents, along with meteorological
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Collecting Volcanic Gas Samples
Steven Ingebritsen (lower right, in blue hat) kneels in the warm mud as he collects samples of the gases emitted from the fumaroles on the north side of Crater Rock on Mount Hood. The samples are taken back to the laboratory for an analysis of the gases' chemical composition. By routinely collecting gas samples and comparing their composition to past measurements,
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Volcanic Gas Sampling
Christoph Kern acquires ultraviolet images of volcanic gas over the dome and crater of Mount St. Helens. Although practically invisible to the human eye, sulfur dioxide absorbs ultraviolet light and appears dark in images captured by the equipment. Sulfur dioxide is typically emitted from magma as it approaches the surface, so surveys are conducted on a regular basis at
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The Air We Breathe…It’s a Gas!
We live at the bottom of an ocean of air. Most adults take around 29,000 breaths a day, children breathe a little faster; but what is in this air we breathe? What are the gases in the air? How much of each gas is there? Do these gases have different weights? How cold are liquid nitrogen and dry ice, and where did those names come from? Come join us to explore these
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