Global & Disaster Medicine

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FEMA: Latest update on Kilauea

Situation Moderate-level eruption of lava continues from multiple points along the northeast end of the active fissure system and additional outbreaks of lava are possible.

Ground deformation has slowed and seismicity levels have decreased.

Lava is entering the ocean just north of MacKenzie State Park and producing laze (an acidic plume of hydrochloric acid gas, steam, and tiny volcanic glass particles).

USCG has issued a Notice to Mariners establishing a safety zone 300 meters in all directions around all entry points of lava into the ocean – all vessels are to remain clear of this zone.

 

USGS Volcano Alert Level: WARNING; Aviation Color Code: RED

Impacts

• Injuries / Fatalities: 4 injuries / 0 fatalities

• Evacuations: Mandatory for 2k residents; a community of 40 homes isolated by lava flow was evacuated over the weekend

• Shelters: 5  / 139 (+21)  (ARC Midnight Shelter Count, 7:17 a.m. EDT)

• Damage: 40 structures (27 homes)

• Transportation: FAA Temporary Flight Restriction in effect through May 26

 

State / Local Response

• HI EOC at Partial Activation (days only)

• Governor declared a State of Emergency and activated HI National Guard FEMA Response

• Region IX: LNO demobilized from HI EOC; RWC and Pacific Area Watch at Steady State

• National IMAT East-1 (with elements of National East-2), and Bothell MERS deployed to HI

• NWC continues to monitor


Kilauea: New eruptions & 1 person injured


Volcanic ashfall in American history


May 18, 1980: Mt. St. Helens erupts; 60 killed

USGS

Prior to 1980, Mount St. Helens had the shape of a conical, youthful volcano sometimes referred to as the Mount Fuji of America. During the 1980 eruption the upper 400 m (1,300 ft) of the summit was removed by a huge debris avalanche, leaving a 2 x 3.5 km (1.2 x 2.2 mi) horseshoe-shaped crater now partially filled by a lava dome and a glacier. It is primarily an explosive dacite volcano with a complex magmatic system.

Mount St. Helens was formed during four eruptive stages beginning about 275,000 years ago and has been the most active volcano in the Cascade Range during the Holocene. Prior to about 12,800 years ago, tephra, lava domes, and pyroclastic flows were erupted, forming the older St. Helens edifice, but a few lava flows extended beyond the base of the volcano. The bulk of the modern edifice (above the 1980 crater floor) was constructed during the last 3,000 years, when the volcano erupted a wide variety of products from summit and flank vents. Historical eruptions in the 19th century originated from the Goat Rocks area on the north flank, and were witnessed by early settlers. New unpublished data on the timing for Mount St. Helens eruptive activity have been analyzed, which improves some of the eruption dates cited in published literature. This website contains the most up to date information.

Since its 1980 eruption, the summit elevation has decreased. A survey in 1982 gave a measurement of 2549.7 m (8365 ft). However, a lidar survey done in 2009 found the maximum elevation to be 2539 m (8330 ft). The difference in elevation is likely due to erosion and loss of rimrock by crater-wall collapses.

Digital Elevation Map of Mount St. Helens with annotation of pre-1980 topography and deposits from 1980 - 2008.


The United States and her 169 potentially active volcanoes

NY Times

 


USGS on Kilauea: Sunday, May 13, 2018, 8:28 PM HST (Monday, May 14, 2018, 06:28 UTC)

USGS

HAWAIIAN VOLCANO OBSERVATORY STATUS REPORT
U.S. Geological Survey
Sunday, May 13, 2018, 8:28 PM HST (Monday, May 14, 2018, 06:28 UTC)

KILAUEA VOLCANO (VNUM #332010)
19°25’16” N 155°17’13” W, Summit Elevation 4091 ft (1247 m)
Current Volcano Alert Level: WARNING
Current Aviation Color Code: ORANGE

Lower East Rift Zone Eruption

Eruption of lava continues from the northeast end of the active fissure system. Residents in lower Puna should remain informed and heed Hawaii County Civil Defense closures, warnings, and messages (http://www.hawaiicounty.gov/active-alerts).

As of late today, activity was dominated by lava fountaining, explosion of spatter bombs hundreds of feet into the air, and several advancing lava flow lobes moving generally northeast from fissure 17 at the downrift (northeast) end of the new fissure system. As of about 7 pm, one lobe was 2 yards thick and advancing roughly parallel to Highway 132. The flow front was just over a half mile southeast of the intersection of Highway 132 and Noni Farms Road.

Based on overflight images late this afternoon, additional lava from fissure 17 was also moving slowly southeast. Volcanic gas emissions remain elevated.

For the most recent map showing the locations of activity, please see https://volcanoes.usgs.gov/volcanoes/kilauea/multimedia_maps.html

HVO field crews are on site overnight tracking the lava flow as conditions allow and reporting information to Hawaii County Civil Defense.

This eruption is still evolving and additional outbreaks of lava are possible. The location of future outbreaks could include areas both uprift (southwest) and downrift (northeast) of the existing fissures, or, existing fissures can be reactivated. Communities downslope of these fissures could be at risk from lava inundation. Activity can change rapidly.

For information on volcanic air pollution, please see: http://www.ivhhn.org/vog/

Kīlauea Volcano Summit

Deflationary tilt continues. A robust plume of steam and volcanic gas, occasionally mixed with ash, has risen from the Overlook crater within Halemaumau. Over the course of the day, rockfalls from the steep walls enclosing the Overlook crater generated ash clouds mixed with steam and gas intermittently throughout the day. These ash clouds have been relatively low concentration and have risen at most only a few thousand feet above the ground, a few generating very localized ashfall downwind. More explosive activity generating larger ash clouds remains possible and can occur with no warning.

Earthquake activity in the summit remains elevated with several strongly felt events at HVO today. Most of these earthquakes are related to the ongoing subsidence of the summit area and earthquakes beneath the south flank of the volcano.

For information on volcanic ash, please see: https://volcanoes.usgs.gov/volcanic_ash/

MORE INFORMATION

Activity Summary also available by phone: (808) 967-8862

Subscribe to these messages: https://volcanoes.usgs.gov/vns2/

Webcam images: https://volcanoes.usgs.gov/volcanoes/kilauea/multimedia_webcams.html

Photos/Video: https://volcanoes.usgs.gov/volcanoes/kilauea/multimedia_chronology.html

Lava Flow Maps: https://volcanoes.usgs.gov/volcanoes/kilauea/multimedia_maps.html

Definitions of terms used in update: https://volcanoes.usgs.gov/volcanoes/kilauea/extra/definitions.pdf

Overview of Kīlauea summit (Halemaʻumaʻu) and East Rift Zone (Puʻu ʻŌʻō ) eruptions:
https://volcanoes.usgs.gov/volcanoes/kilauea/extra/background.pdf

Summary of volcanic hazards from Kīlauea eruptions:
https://volcanoes.usgs.gov/volcanoes/kilauea/extra/hazards.pdf

Recent Earthquakes in Hawai’i (map and list):
https://volcanoes.usgs.gov/hvo/earthquakes/

Explanation of Volcano Alert Levels and Aviation Color Codes:
https://volcanoes.usgs.gov/activity/alertsystem/index.php
https://pubs.usgs.gov/fs/2006/3139/

CONTACT INFORMATION:

askHVO@usgs.gov

The Hawaiian Volcano Observatory is one of five volcano observatories within the U.S. Geological Survey and is responsible for monitoring volcanoes and earthquakes in Hawai`i.


USGS Volcano Glossary

USGS

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Kilauea: Definitions of Volcanic Terms (USGS)

USGS

• DI event: “DI” is short for “deflation-inflation.” A DI event is an abrupt deflation of Kīlauea’s summit that lasts from several hours to 2-3 days, followed by an abrupt transition to inflation that effectively cancels the preceding deflation over the ensuing hours to days. DI events are best recorded by tiltmeters at Kīlauea’s summit, which typically measure a few microradians (see definition below) of change for individual events. DI events indicate a decrease and subsequent increase in pressure within a magma reservoir located about 1.5 km (1 mi) beneath the east margin of Halema‘uma‘u Crater. The level of the summit lava lake generally tracks tilt during DI events, with the lava level dropping during the deflation phase and rising during the inflation phase. Many DI events at Kīlauea’s summit are also recorded, after a delay of minutes to hours, by a tiltmeter on the north flank of Pu‘u ‘Ō‘ō on Kīlauea’s East Rift Zone, which is a sign that the pressure changes at the summit are being transmitted through the magma conduit to the East Rift Zone eruption site. DI events sometimes correlate with pauses and pulses in lava output from East Rift Zone eruptive vents. For more information, please go to: http://hvo.wr.usgs.gov/volcanowatch/view.php?id=117 http://hvo.wr.usgs.gov/howwork/subsidence/inflate_deflate.html

• Glow: Light from an unseen source; indirect light.

• Halema‘uma‘u Overlook: This visitor overlook, located on the southeast rim of Halema‘uma‘u Crater, has been closed to the public since early 2008, when sulfur dioxide gas emissions increased to hazardous levels. After the summit vent opened within Halema‘uma‘u Crater in March 2008, the visitor overlook area became even more hazardous. High levels of sulfur dioxide gas can pose an immediate danger to health and life, and intermittent explosive eruptions blast rock and lava fragments (some large enough to cause serious injury or death) from the vent on to the crater rim.

• Overlook vent or Overlook crater: The informal name of Kīlauea Volcano’s active summit vent. This vent is a crater within the floor of Halema‘uma‘u Crater, which, in turn, is within the floor of the larger Kīlauea caldera (also sometimes referred to as a crater). When the summit vent first opened in March 2008, it was about 35 m (115 ft) in diameter. It has since enlarged due to collapses of the overhung vent rim, and, as of May 2015, was about 215 m (705 ft) by 165 m (540 ft) in size. From November 2009 to present, the summit vent has hosted a lava lake that has risen and fallen dramatically over time, with lake levels that have ranged from about 200 m (655 ft) below the vent rim (e.g., in January 2010) to overflowing the vent rim (e.g., in April-May 2015). Lava lake level fluctuations—rising with summit inflation and dropping with summit deflation— are an ongoing process. For more information, please go to: http://pubs.usgs.gov/fs/2013/3116/

• Incandescence: Visible light emitted from a hot surface. The color of the light is related to surface temperature. Molten lava displays bright orange to orange-yellow light from surfaces that
are hotter than 900 degrees Celsius (1,650 degrees Fahrenheit). Some surfaces can display dull red incandescence at temperatures as low as 430 degrees Celsius (806 degrees Fahrenheit). • Jaggar Museum Overlook (or observation deck): Perched on the rim of Kīlauea Volcano’s summit caldera, about 1.6 km (1 mi) north-northwest of the active summit vent within Halema‘uma‘u Crater, the Jaggar Museum Overlook (observation deck) affords spectacular views of Kīlauea’s summit vent activity. The Thomas A. Jaggar Museum is located on Crater Rim Drive in Hawai‘i Volcanoes National Park about 4 km (2.5 mi) from the Kīlauea Visitor Center. For more information, please visit: http://www.nps.gov/havo/planyourvisit/jaggar_museum.htm

• Metric ton (t): A unit of weight or mass equal to 1,000 kilograms, 2,204.6 lbs, or 1.102 US (short) tons. Used to report gas measurements.

• Microradian: The amount of tilt or ground deformation on volcanoes is measured in microradians. One microradian of tilt is equivalent to the angle created by raising one end of a 1km- (0.6-mi-) long board by the thickness of a U.S. dime (1 mm, or 0.04 in). More specifically, a microradian is a measure of angle equivalent to 0.000057 degrees. For more information about tilt, please visit: http://volcanoes.usgs.gov/activity/methods/deformation/tilt/. http://hvo.wr.usgs.gov/kilauea/update/deformation.php http://hvo.wr.usgs.gov/volcanowatch/archive/2002/02_05_30.html

• Tephra: The general term for volcanic rock fragments exploded or carried into the air during an eruption. Such fragments can range in size from less than 2 mm (0.08 inches) to more than 1 m (3.2 feet) in diameter. The smallest tephra is called volcanic ash, pieces of pulverized rock and volcanic glass the size of sand or silt. Tiny ash particles can be less than 0.001 mm (0.00004 inches) in diameter. For more information about tephra, please visit: http://hvo.wr.usgs.gov/hazards/FAQ_SO2-Vog-Ash/P2.html#ash http://volcanoes.usgs.gov/hazards/tephra/ http://volcanoes.usgs.gov/images/pglossary/tephra.php http://volcanoes.usgs.gov/hazards/tephra/tephraterms.php

• Tonne (t): An old spelling for “metric ton,” a unit that is used to report gas measurements.

For more definitions of volcanic terms (with photos), please see: http://volcanoes.usgs.gov/images/pglossary/

EARTHQUAKE TERMS:
• LPs: Long-period (LP) events refer to a type of earthquake with a drawn-out, wave-like pattern when viewed on seismic records (seismograms). LP earthquakes are attributed to motion of fluids (gas, water, and/or magma) within conduits, cracks, and chambers beneath the ground surface, and have a gentler, rolling motion that is difficult for humans to detect. Most earthquakes that people feel are short-period events associated with rupture of a fault, with chaotic, rapid changes in ground motion. On seismograms, LP earthquakes are recognized by the relatively even spacing between adjacent peaks on the record. This spacing—or period—can be between 0.2 and 2 seconds
(frequencies of 0.5 to 5 Hz), compared to short-period earthquakes, which are characterized by periods that are fractions of a second. LP earthquakes are also known at other volcanoes as low-frequency earthquakes, tornillos, or B-type earthquakes

• VLPs: Very-long-period (VLP) events are earthquakes similar to LP events, but with much longer periods (that is, more time between adjacent peaks on a seismic record)—typically between 20 and 100 seconds (frequencies between 0.01 and 0.05 Hz). If LP earthquakes are analogous to waves on the ocean, then VLP earthquakes are like ocean swells. VLPs can only be detected by specially designed seismometers, since the “shaking” is so gentle. At Kīlauea, VLP earthquakes are common and associated with magma and gas migration through a constriction located near a shallow magma reservoir about 1.5 km (1 mi) beneath Halema‘uma‘u Crater.

• Composite seismic event: A composite seismic event records several processes occurring one after another—a combination of short-period, long-period (LP) and very-long-period (VLP) earthquakes that occur as part of a single, drawn-out event. These events have been recorded frequently at Kīlauea since the start of the current summit eruption in March 2008, and are usually associated with rockfalls into the summit lava lake (as seen by HVO cameras). Composite seismic events typically begin like “normal” short-period earthquakes, with chaotic shaking indicating the occurrence of a rockfall and small explosion as the rockfall makes contact with the lava lake. After a few seconds, the seismic signature transitions to an LP event as gas is released from the upper part of the lava lake. The disturbance in the column of lava in the lake is felt all the way down to a small magma chamber beneath the summit, where it triggers the release of VLP energy that follows the LP event. Thus, a composite seismic event begins like a normal earthquake, but transitions to an LP and then a VLP event, the latter of which can last for several minutes before the energy dissipates completely.

• Volcanic tremor: Active volcanoes are characterized by continuous release of seismic energy as fluids (magma, gas, and/or water) move through subsurface conduits, as gas is released from magma, and/or as lava erupts at the surface. This background seismic “hum” of the volcano is called volcanic tremor. Volcanic tremor is frequently associated with gas and lava output and is often a sign that a volcano is erupting or is on the verge of erupting. Volcanic tremor is distinguished from earthquakes by its sustained nature, lasting from minutes to days and fluctuating in intensity, depending on the activity of the volcano. Harmonic tremor refers to volcanic tremor displaying a steady or dominant period associated with ground shaking. Spasmodic tremor features bursts of energy.

OTHER TERMS / HAWAIIAN WORDS:
• CD: Hawai‘i County Civil Defense

• Mauka / makai: Hawaiian terms for directions relative to the coast. Makai or ma kai is toward the coast, and mauka or ma uka is toward the highlands, or away from the coast.
• Pali: Hawaiian term for cliff or precipice.


Kilauea: 1,700 people have been evacuated, and many homes have been consumed by fire.

USGS

“…..Since eruptions in the Leilani Estates neighborhood began on May 3, the flows of lava have destroyed 36 structures as of Friday — at least 26 of them homes — and covered 117 acres.…..”

HAWAIIAN VOLCANO OBSERVATORY STATUS REPORT
U.S. Geological Survey
Friday, May 11, 2018, 4:39 PM HST (Saturday, May 12, 2018, 02:39 UTC)

KILAUEA VOLCANO (VNUM #332010)
19°25’16” N 155°17’13” W, Summit Elevation 4091 ft (1247 m)
Current Volcano Alert Level: WARNING
Current Aviation Color Code: ORANGE

Lower East Rift Zone Eruption
Volcanic unrest in the lower East Rift Zone of Kīlauea Volcano continues. While no lava has been emitted from any of the 15 fissure vents since May 9, earthquake activity, ground deformation, and continuing high emission rates of sulphur dioxide indicate additional outbreaks of lava are likely. The location of future outbreaks is not known with certainty, but could include areas both uprift (southwest) and downrift (northeast) of the existing fissures, or resumption of activity at existing fissures. Communities downslope of these fissures could be at risk from lava inundation.

Residents in lower Puna should remain informed and heed Hawaii County Civil Defense closures, warnings, and messages (http://www.hawaiicounty.gov/active-alerts).

For maps showing the locations of eruption features, please see https://volcanoes.usgs.gov/volcanoes/kilauea/multimedia_maps.html

For information on volcanic air pollution, please see: http://www.ivhhn.org/vog/

Kīlauea Volcano Summit
Tiltmeters at the summit of Kīlauea Volcano continue to record deflationary tilt. Based on this and field observations of the past two days, the lava lake level continues to drop. Rockfalls from the steep crater walls have generated small ash clouds mixed with white condensed water vapor intermittently throughout the day. These ash clouds have been relatively low concentration and have risen only a few thousand feet above the ground generating very localized ashfall. More explosive activity generating larger ash clouds remains possible.

Earthquake activity in the summit remains elevated. Many of these earthquakes are related to the ongoing subsidence of the summit area and earthquakes beneath the south flank of the volcano.

For information on volcanic ash, please see: https://volcanoes.usgs.gov/volcanic_ash/

MORE INFORMATION

Activity Summary also available by phone: (808) 967-8862

Subscribe to these messages: https://volcanoes.usgs.gov/vns2/

Webcam images: https://volcanoes.usgs.gov/volcanoes/kilauea/multimedia_webcams.html

Photos/Video: https://volcanoes.usgs.gov/volcanoes/kilauea/multimedia_chronology.html

Lava Flow Maps: https://volcanoes.usgs.gov/volcanoes/kilauea/multimedia_maps.html

Definitions of terms used in update: https://volcanoes.usgs.gov/volcanoes/kilauea/extra/definitions.pdf

Overview of Kīlauea summit (Halemaʻumaʻu) and East Rift Zone (Puʻu ʻŌʻō ) eruptions:
https://volcanoes.usgs.gov/volcanoes/kilauea/extra/background.pdf

Summary of volcanic hazards from Kīlauea eruptions:
https://volcanoes.usgs.gov/volcanoes/kilauea/extra/hazards.pdf

Recent Earthquakes in Hawai’i (map and list):
https://volcanoes.usgs.gov/hvo/earthquakes/

Explanation of Volcano Alert Levels and Aviation Color Codes:
https://volcanoes.usgs.gov/activity/alertsystem/index.php
https://pubs.usgs.gov/fs/2006/3139/

CONTACT INFORMATION:

askHVO@usgs.gov

The Hawaiian Volcano Observatory is one of five volcano observatories within the U.S. Geological Survey and is responsible for monitoring volcanoes and earthquakes in Hawai`i.


Sulfur Dioxide Leaks from Kilauea

Sulfur Dioxide Leaks from Kilauea

Kilauea has been erupting continuously since 1983, but in late April and early May 2018 the volcanic eruption took a dangerous new turn.

During the last week of April, the lava lake at Halema‘uma‘u Overlook crater overflowed several times and then began to drain rapidly after the crater floor partially collapsed. Soon after, a swarm of earthquakes spread across Kilauea’s East Rift Zone as magma moved underground. On May 3, 2018, several new fissures cracked open the land surface in the Leilani Estates subdivision, leaking gases and spewing fountains of lava. As of May 7, 2018, slow-moving lava flows had consumed 35 homes in that community of 1,500 people.

acquired May 3, 2018 download large image (5 MB, JPEG, 4032×2688)

In addition to seismic activity and deformation of the land surface, another sign of volcanic activity is increased emission of sulfur dioxide (SO2), a toxic gas that occurs naturally in magma. When magma is deep underground, the gas remains dissolved because of the high pressure. However, pressure diminishes as magma rises toward the surface, and gas comes out of solution, or exsolves, forming bubbles in the liquid magma.

“The process is similar to what happens when a bottle of soda is opened,” explained Ashley Davies, a volcanologist at NASA’s Jet Propulsion Laboratory. “The bubbles of sulfur dioxide and other volatiles, including water and carbon dioxide, begin to rise through the liquid magma and concentrate in the magma closest to the surface, so the first lava to erupt is often the most volatile-rich. There’s usually an increase in sulfur dioxide output right before lava reaches the surface, as the gas escapes from the ascending magma.”

Sensors onboard the Ozone Mapping Profiler Suite (OMPS) sensor on the Suomi NPP satellite have begun to detect signs of activity at Kilauea. The series of images above shows elevated concentrations of sulfur dioxide on May 5, a few days after the new fissures opened up. The second chart (below) underscores the significant natural variability in sulfur dioxide emissions as observed by OMPS over Hawaii between January and May 2018.

acquired January 1 – May 5, 2018

“Interpreting the satellite SO2 data for events like this is complicated because there are multiple SO2 sources that combine to form the volcanic sulfur dioxide plume. Kilauea volcano has several sources of sulfur dioxide degassing: the summit caldera (a significant source since 2008); the Pu’u ‘O’o vent on the East Rift Zone; and now the new eruption site in Leilani Estates,” said Simon Carn, a volcanologist at Michigan Tech. “It can be very hard to distinguish individual ‘plumes’ from these sulfur dioxide sources with the spatial resolution that we have from OMPS, but we are seeing what seems to be an overall increase that coincides with the latest activity.”

Another satellite-based sensor—the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA’s Terra satellite—observed SO2 emissions on on May 6, 2018. When ASTER passed over Hawaii, the largest source of SO2 appeared to be coming from Kilauea’s summit crater, but there was also a sizable plume streaming southwest from the fissures in Leilani Estates. So far, trade winds have pushed the toxic gas offshore, but Hilo and other communities northwest of Leilani Estates could see air quality deteriorate if the trade winds weaken.

NASA Earth Observatory images by Joshua Stevens, using OMPS data from the Goddard Earth Sciences Data and Information Services Center (GES DISC). Photo courtesy of the U.S. Geological Survey. Story by Adam Voiland, with information from Simon Carn (Michigan Tech), Nickolay Krotkov (NASA Goddard Space Flight Center), Ashley Davies (NASA Jet Propulsion Laboratory), Janine Krippner (Concord University), and Jean-Paul Vernier (NASA Langley Research Center).


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