Who monitors volcanic gases emitted by Kīlauea and how is it done??

The U.S. Geological Survey's Hawaiian Volcano Observatory (HVO) determines the amount and composition of gases emitted by Kīlauea Volcano. Changes in gas emissions can reveal important clues about the inner workings of a volcano, so they are measured on a regular basis.

HVO scientists use both remote and direct sampling techniques to measure compositions and emission rates of gas from Kīlauea Volcano.

To determine the rate at which sulfur dioxide (SO2) is emitted, HVO scientists measure the amount of ultraviolet (UV) radiation energy absorbed by the volcanic gas plume as sunlight passes through it. They do this by attaching a mini-UV spectrometer (Flyspec) to a field vehicle and driving beneath the plume.

The amount of carbon dioxide (CO2) emitted by Kīlauea is measured using a small infrared analyzer (LI-COR). Scientists drive this instrument through a gas plume, along with the Flyspec, while it continuously and directly samples the ground-level cross-section of the plume.

Another tool used to measure the relative abundance of some gases, including SO2, CO2, hydrogen chloride (HCl), hydrogen fluoride (HF), carbon monoxide (CO) and water vapor (H20), is the Fourier Transform infrared spectrometer (FTIR), which can continuously sample gas in a volcanic plume. The FTIR measures the amount of light absorbed by gases along an open path between the spectrometer and an infrared source, such as an eruptive vent. 

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Does vog (volcanic smog) impact plants and animals?

The sulfuric acid droplets in vog have the corrosive properties of dilute battery acid. When vog mixes directly with moisture on the leaves of plants it can cause severe chemical burns, which can damage or kill the plants. Sulfur dioxide (SO2) gas can also diffuse through leaves and dissolve to form acidic conditions within plant tissue. Farmers...

What gases are emitted by Kīlauea and other active volcanoes?

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Where and how do sulfur dioxide and volcanic gases (vog) affect air quality in Hawaii?

The most critical factors that determine how much vog impacts an area are wind direction and speed. Air temperature, humidity, rainfall, location of the source, and the amount of sulfur dioxide (SO2) being emitted are also factors. During prevailing trade (from northeast) wind conditions, any SO2 emitted from Pu`u `Ō `ō is blown out to sea, while...

How much sulfur dioxide (SO2) gas does Kīlauea emit?

Kīlauea typically emits between 500 and 14,000 metric tons of sulfur dioxide gas (SO2) per day during periods of sustained eruption. During the 2018 eruption at Kīlauea’s Lower East Rift Zone, SO2 emissions were over 30,000 metric tons per day, in keeping with the increased vigor of that eruption. Methods for calculating emission rates for SO2 can...

Should I cancel my plans to visit to Hawai`i Island because of sulfur dioxide (SO2) and vog?

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What health hazards are posed by vog (volcanic smog)?

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What is "vog"? How is it related to sulfur dioxide (SO2) emissions?

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Does ash ever erupt from Kīlauea Volcano??

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Why is it important to monitor volcanoes?

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What kind of school training do you need to become a volcanologist?

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Filter Total Items: 5
Date published: May 18, 2017

EarthWord–Vog

Just like smog and fog, this EarthWord is not what you want to see while driving...

Date published: August 18, 2016

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.

Date published: October 5, 2015

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.

Date published: February 11, 2015

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.

Date published: June 20, 2007

Hazardous Sulfur Dioxide Concentrations Measured at Kilauea Volcano

Today, HVO scientists measured concentrations greater than 10 ppm in a broad area adjacent to Halema‘uma‘u crater. Sulfur Dioxide gas is persistently emitted at Kîlauea's summit. Typical concentrations are generally negligible except for areas downwind of Halema‘uma‘u crater, where they can get up to 2.5 ppm (parts-per-million) in narrow zones.

Filter Total Items: 14
December 31, 2018

Hovering Above—UAS’ Role in the 2018 Kīlauea Volcano Eruption Response

The 2018 Kīlauea Volcano eruption marked the first time the federal government used Unmanned Aircraft Systems (UAS) to assist in an eruption response in the United States. The UAS were used to survey areas otherwise inaccessible or too hazardous for field crews or manned aircraft, collect multiple types of data, and provide 24/7 real-time situational awareness at Kīlauea

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August 30, 2018

PubTalk 8/2018 — What on Earth is going on at Kilauea Volcano?

Title: What on Earth is going on at Kilauea Volcano?

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scientist with camera and spectrometer at the edge of smoking volcanic crater.
August 16, 2016

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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White gas plume rising straight up from Kilauea Volcano summit with distant, bright, full moon.
August 16, 2016

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.

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July 8, 2016

Taking Lava Temps

In this photo, a USGS researcher is taking a temperature measurement on a sluggish channel eddy on Kīlauea Volcano in 1984. The research in Hawaiʻi is just one of many projects overseen by the USGS Volcano Hazards Program, which monitors active and potentially active volcanoes, assesses their hazards, responds to volcanic crises, and

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A USGS geologist collects a molten lava sample during a December 2015 lava flow from Puʻu ʻŌʻō.
April 27, 2016

A USGS geologist collects a molten lava sample during a December 2015 lava flow from Puʻu ʻŌʻō.

A USGS geologist collects a molten lava sample during a December 2015 lava flow from Puʻu ʻŌʻō. As the lava cools on the surface, its viscosity increases and the flow slows down. Credit: USGS.

Image: Monitoring Volcanic Gases on Kilauea's East Rift Zone II
May 31, 2014

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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Image: Monitoring Volcanic Gases on Kilauea's East Rift Zone
May 31, 2014

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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Scientist shields face while scooping lava with a hammer for chemical analysis
October 21, 2013

HVO geologist shields face from intense lava-flow heat while taking a fresh sample.

An HVO geologist shields his face from the intense heat as he takes a sample of active lava on the Kahaualeʻa 2 flow, Kilauea Volcano Hawaii.  The chemistry of the lava is analyzed through time and used to study changes in the magmatic system.  

video thumbnail: Volcano Hazards
July 30, 2012

Volcano Hazards

The United States has 169 active volcanoes. More than half of them could erupt explosively, sending ash up to 20,000 or 30,000 feet where commercial air traffic flies. USGS scientists are working to improve our understanding of volcano hazards to help protect communities and reduce the risks.

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Image: Deploying a FTIR on Pu’u ‘Ō’ō crater
June 3, 2010

Deploying a FTIR on Pu’u ‘Ō’ō crater

HVO gas geochemists deployed a FTIR spectrometer on the east rim of Pu`u `Ō `ō crater. The FTIR measures the composition of the East Wall vent gases by "looking" through the plume at an infrared lamp (obscured by fume in this photo)

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Image: Deploying a FTIR on Pu’u ‘Ō’ō crater
June 3, 2010

Deploying a FTIR on Pu’u ‘Ō’ō crater

This photo was taken from the lamp on the other side of the plume. The FTIR is the small dark silhouette on the rim across the crater gap.

Attribution: