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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 any SO2 from the summit vent often creates vog in Ka`u communities from Pahala to Ocean View. SO2 emissions from the Lower East rift zone blow downwind to the Kona coast. Unfortunately, multiple plumes can eventually reach the west side of Hawai`i Island in a "double-whammy" of combined effects, resulting in an especially dense and nearly constant haze of vog along the Kona coast.
When the winds become light and variable or blow from the south, communities in East Hawai`i and along the entire Hawaiian Island chain can also suffer the effects of vog. Under these conditions, people living in the path of gas emissions continue to experience vog levels similar to those that have beset them for over two decades. Communities in the path of summit SO2 emissions, particularly those nearest the source vent, can be subjected to an unusually acrid haze that contains both gas and acidic particles because the emissions have had little time to disperse and dilute before reaching them.
Learn more:
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 (SO 2 ) gas can also diffuse through leaves and dissolve to form acidic conditions within plant tissue. Farmers on Hawai`i Island, particularly in the Ka`u...
Predicting the vog levels that visitors might experience during a short stay in Hawai`i is as difficult as predicting the weather. Once volcanic emissions are in the atmosphere, they are distributed by prevailing winds. Where and how bad the vog is ultimately depends on several factors including wind direction, wind speed, air temperature, humidity, and rainfall, as well as the location of the...
Vog poses a health hazard by aggravating preexisting respiratory ailments. Sulfur dioxide (SO 2 ) gas can irritate skin and the tissues and mucous membranes of the eyes, nose, and throat, and can penetrate airways, producing respiratory distress in some individuals. Aerosol particles in vog can also penetrate deep into human lungs and, at elevated levels, can induce symptoms of asthma. Physical...
Vog (volcanic smog) is a visible haze comprised of gas and an aerosol of tiny particles and acidic droplets created when sulfur dioxide (SO 2 ) and other gases emitted from a volcano chemically interact with sunlight and atmospheric oxygen, moisture, and dust. Volcanic gas emissions can pose environmental and health risks to nearby communities. Vog is a hazard that's associated with Hawaiian...
Ninety-nine percent of the gas molecules emitted during a volcanic eruption are water vapor (H 2 O), carbon dioxide (CO 2 ), and sulfur dioxide (SO 2 ). 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: Volcanic gases can be harmful to health, vegetation and infrastructure
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...
Kīlauea typically emits between 500 and 14,000 metric tons of sulfur dioxide gas (SO 2 ) per day during periods of sustained eruption. During the 2018 eruption at Kīlauea’s Lower East Rift Zone, SO 2 emissions were over 100,000 metric tons per day, in keeping with the increased vigor of that eruption. Methods for calculating emission rates for SO 2 can be complicated and challenging in the high...
Kīlauea Volcano is renowned for its relatively benign eruptions of fluid lava flows. Therefore, many people were surprised by the small explosions that occurred in Halema`uma`u Crater in 2008 and 2018, and even more surprised to learn that volcanic ash was being erupted from a new gas vent. However, ash emissions from Halema`uma`u Crater are part of the volcano's legacy. Kīlauea's summit has...
Not usually. Earthquakes associated with eruptions rarely exceed magnitude 5, and these moderate earthquakes are not big enough to destroy buildings and roads. The largest earthquakes at Mount St. Helens in 1980 were magnitude 5, large enough to sway trees and damage buildings, but not destroy them. During the huge eruption of Mount Pinatubo in the Philippines in 1991, dozens of light to moderate...
There are 161 potentially active volcanoes in the United States. According to a 2018 USGS assessment , 57 volcanoes are a high threat or very high threat to public safety. Many of these volcanoes have erupted in the recent past and will erupt again in the foreseeable future. As populations increase, areas near volcanoes are being developed and aviation routes are increasing. As a result, more...
Volcanoes are inherently beautiful places where forces of nature combine to produce awesome events and spectacular landscapes. For volcanologists, they're FUN to work on! Safety is, however, always the primary concern because volcanoes can be dangerous places. USGS scientists try hard to understand the risk inherent in any situation, then train and equip themselves with the tools and support...
Title: What on Earth is going on at Kilauea Volcano?
Title: What on Earth is going on at Kilauea Volcano?
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.
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.
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.
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.
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.
Video Sections:
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.
Video Sections:
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?
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?
A beautiful example of sulfur crystals that have grown around a small fumarole near the southeast rim of Halema`uma`u crater. The vent is about 0.3 m (1 foot) long.
A beautiful example of sulfur crystals that have grown around a small fumarole near the southeast rim of Halema`uma`u crater. The vent is about 0.3 m (1 foot) long.
The erupting vent within Halema'uma'u Crater at Kilauea's summit (see http://hvo.wr.usgs.gov/kilauea/timeline/ for links describing eruptive activity at the summit of Kilauea Volcano) typically produces a white to gray gas plume dominated by steam.
The erupting vent within Halema'uma'u Crater at Kilauea's summit (see http://hvo.wr.usgs.gov/kilauea/timeline/ for links describing eruptive activity at the summit of Kilauea Volcano) typically produces a white to gray gas plume dominated by steam.
The USGS Hawaiian Volcano Observatory (foreground) is located on the caldera rim of Kilauea Volcano, Hawai'i—the most active volcano in the world. The observatory's location provides an excellent view of summit eruptive activity, which began in 2008.
The USGS Hawaiian Volcano Observatory (foreground) is located on the caldera rim of Kilauea Volcano, Hawai'i—the most active volcano in the world. The observatory's location provides an excellent view of summit eruptive activity, which began in 2008.
Ash-rich plume rises out of Halemaʻumaʻu Crater, Kilauea Volcano Hawaiʻi.
Ash-rich plume rises out of Halemaʻumaʻu Crater, Kilauea Volcano Hawaiʻi.
The rim of Kīlauea Volcano’s summit caldera, normally clear on trade-wind days (left), became nearly obscured by vog (right) on some non-trade wind days beginning in 2008, when sulfur dioxide emissions from the volcano’s summit increased to unusually high levels. (This photo has been edited.)
The rim of Kīlauea Volcano’s summit caldera, normally clear on trade-wind days (left), became nearly obscured by vog (right) on some non-trade wind days beginning in 2008, when sulfur dioxide emissions from the volcano’s summit increased to unusually high levels. (This photo has been edited.)
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 (SO 2 ) gas can also diffuse through leaves and dissolve to form acidic conditions within plant tissue. Farmers on Hawai`i Island, particularly in the Ka`u...
Predicting the vog levels that visitors might experience during a short stay in Hawai`i is as difficult as predicting the weather. Once volcanic emissions are in the atmosphere, they are distributed by prevailing winds. Where and how bad the vog is ultimately depends on several factors including wind direction, wind speed, air temperature, humidity, and rainfall, as well as the location of the...
Vog poses a health hazard by aggravating preexisting respiratory ailments. Sulfur dioxide (SO 2 ) gas can irritate skin and the tissues and mucous membranes of the eyes, nose, and throat, and can penetrate airways, producing respiratory distress in some individuals. Aerosol particles in vog can also penetrate deep into human lungs and, at elevated levels, can induce symptoms of asthma. Physical...
Vog (volcanic smog) is a visible haze comprised of gas and an aerosol of tiny particles and acidic droplets created when sulfur dioxide (SO 2 ) and other gases emitted from a volcano chemically interact with sunlight and atmospheric oxygen, moisture, and dust. Volcanic gas emissions can pose environmental and health risks to nearby communities. Vog is a hazard that's associated with Hawaiian...
Ninety-nine percent of the gas molecules emitted during a volcanic eruption are water vapor (H 2 O), carbon dioxide (CO 2 ), and sulfur dioxide (SO 2 ). 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: Volcanic gases can be harmful to health, vegetation and infrastructure
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...
Kīlauea typically emits between 500 and 14,000 metric tons of sulfur dioxide gas (SO 2 ) per day during periods of sustained eruption. During the 2018 eruption at Kīlauea’s Lower East Rift Zone, SO 2 emissions were over 100,000 metric tons per day, in keeping with the increased vigor of that eruption. Methods for calculating emission rates for SO 2 can be complicated and challenging in the high...
Kīlauea Volcano is renowned for its relatively benign eruptions of fluid lava flows. Therefore, many people were surprised by the small explosions that occurred in Halema`uma`u Crater in 2008 and 2018, and even more surprised to learn that volcanic ash was being erupted from a new gas vent. However, ash emissions from Halema`uma`u Crater are part of the volcano's legacy. Kīlauea's summit has...
Not usually. Earthquakes associated with eruptions rarely exceed magnitude 5, and these moderate earthquakes are not big enough to destroy buildings and roads. The largest earthquakes at Mount St. Helens in 1980 were magnitude 5, large enough to sway trees and damage buildings, but not destroy them. During the huge eruption of Mount Pinatubo in the Philippines in 1991, dozens of light to moderate...
There are 161 potentially active volcanoes in the United States. According to a 2018 USGS assessment , 57 volcanoes are a high threat or very high threat to public safety. Many of these volcanoes have erupted in the recent past and will erupt again in the foreseeable future. As populations increase, areas near volcanoes are being developed and aviation routes are increasing. As a result, more...
Volcanoes are inherently beautiful places where forces of nature combine to produce awesome events and spectacular landscapes. For volcanologists, they're FUN to work on! Safety is, however, always the primary concern because volcanoes can be dangerous places. USGS scientists try hard to understand the risk inherent in any situation, then train and equip themselves with the tools and support...
Title: What on Earth is going on at Kilauea Volcano?
Title: What on Earth is going on at Kilauea Volcano?
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.
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.
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.
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.
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.
Video Sections:
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.
Video Sections:
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?
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?
A beautiful example of sulfur crystals that have grown around a small fumarole near the southeast rim of Halema`uma`u crater. The vent is about 0.3 m (1 foot) long.
A beautiful example of sulfur crystals that have grown around a small fumarole near the southeast rim of Halema`uma`u crater. The vent is about 0.3 m (1 foot) long.
The erupting vent within Halema'uma'u Crater at Kilauea's summit (see http://hvo.wr.usgs.gov/kilauea/timeline/ for links describing eruptive activity at the summit of Kilauea Volcano) typically produces a white to gray gas plume dominated by steam.
The erupting vent within Halema'uma'u Crater at Kilauea's summit (see http://hvo.wr.usgs.gov/kilauea/timeline/ for links describing eruptive activity at the summit of Kilauea Volcano) typically produces a white to gray gas plume dominated by steam.
The USGS Hawaiian Volcano Observatory (foreground) is located on the caldera rim of Kilauea Volcano, Hawai'i—the most active volcano in the world. The observatory's location provides an excellent view of summit eruptive activity, which began in 2008.
The USGS Hawaiian Volcano Observatory (foreground) is located on the caldera rim of Kilauea Volcano, Hawai'i—the most active volcano in the world. The observatory's location provides an excellent view of summit eruptive activity, which began in 2008.
Ash-rich plume rises out of Halemaʻumaʻu Crater, Kilauea Volcano Hawaiʻi.
Ash-rich plume rises out of Halemaʻumaʻu Crater, Kilauea Volcano Hawaiʻi.
The rim of Kīlauea Volcano’s summit caldera, normally clear on trade-wind days (left), became nearly obscured by vog (right) on some non-trade wind days beginning in 2008, when sulfur dioxide emissions from the volcano’s summit increased to unusually high levels. (This photo has been edited.)
The rim of Kīlauea Volcano’s summit caldera, normally clear on trade-wind days (left), became nearly obscured by vog (right) on some non-trade wind days beginning in 2008, when sulfur dioxide emissions from the volcano’s summit increased to unusually high levels. (This photo has been edited.)
