Hazard Notification System (HANS) for Volcanoes
HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE
U.S. Geological Survey
Sunday, February 26, 2023, 8:53 AM HST (Sunday, February 26, 2023, 18:53 UTC)
KILAUEA VOLCANO (VNUM #332010)
19°25'16" N 155°17'13" W, Summit Elevation 4091 ft (1247 m)
Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE
Activity Summary: The summit eruption of Kīlauea Volcano, within Halemaʻumaʻu crater, continues to be greatly diminished over the past 6 days. All recent eruptive activity has been confined to the crater. No significant changes have been observed in either rift zone.
Halemaʻumaʻu Lava Lake Observations: Eruption of lava on the Halemaʻumaʻu crater floor continues to be greatly diminished over the past 6 days. The eastern and central vents are not erupting. The western lake in the basin of the 2021–22 lava lake remains active but with weak lava flows. Very little lava is circulating within the lake, which is mostly crusted over with intermittent crustal overturns. The reduction in activity is related to the larger deflationary tilt drop that began in the early morning of February 17. Tilt continues to increase slowly. Surface eruptive activity is expected to resume when the summit re-inflates to the levels observed in the prior week. A live-stream video of the western lava lake is available at: https://www.youtube.com/usgs/live.
Summit Observations: Over the past 6 days summit tiltmeters showed small scale deflation/inflation cycles but have not returned to the levels seen prior to Feberuary 17th. Volcanic tremor has dropped slightly but remains above background levels. A sulfur dioxide (SO2) emission rate of approximately 2,000 tonnes per day (t/d) was measured on February 13, 2023.
Rift Zone Observations: No unusual activity has been noted along the East Rift Zone or Southwest Rift Zone; steady rates of ground deformation and seismicity continue along both. Measurements from continuous gas monitoring stations downwind of Puʻuʻōʻō in the middle East Rift Zone have been below detection limits for SO2, indicating that SO2 emissions from Puʻuʻōʻō are negligible.
Hazard Analysis: This eruption at Kīlauea's summit is occurring within a closed area of Hawaiʻi Volcanoes National Park. High levels of volcanic gas are the primary hazard of concern, as this hazard can have far-reaching effects downwind. Large amounts of volcanic gas—primarily water vapor (H2O), carbon dioxide (CO2), and sulfur dioxide (SO2)—are continuously released during eruptions of Kīlauea Volcano. As SO2 is released from the summit, it reacts in the atmosphere to create the visible haze known as vog (volcanic smog) that has been observed downwind of Kīlauea. Vog creates the potential for airborne health hazards to residents and visitors, damages agricultural crops and other plants, and affects livestock. For more information on gas hazards at the summit of Kīlauea, please see: https://pubs.er.usgs.gov/publication/fs20173017. Vog information can be found at https://vog.ivhhn.org.
Additional hazards include Pele's hair and other lightweight volcanic glass fragments from lava fountains that will fall downwind and dust the ground within a few hundred meters (yards) of the erupting fissure vent(s). Strong winds may waft lighter particles to greater distances. Residents should minimize exposure to these volcanic particles, which can cause skin and eye irritation.
Other significant hazards also remain around Kīlauea caldera from Halemaʻumaʻu crater wall instability, ground cracking, and rockfalls that can be enhanced by earthquakes within the area closed to the public. This underscores the extremely hazardous nature of the rim surrounding Halemaʻumaʻu crater, an area that has been closed to the public since early 2008.
For discussion of Kīlauea hazards, please see: https://www.usgs.gov/observatories/hawaiian-volcano-observatory/hazards.
Please see the Hawaiʻi Volcanoes National Park website for visitor information: https://www.nps.gov/havo/index.htm. Visitors to Hawaiʻi Volcanoes National Park should note that under southerly (non-trade) wind conditions, there is potential for a dusting of powdery to gritty ash composed of volcanic glass and rock fragments. These ashfalls represent a minor hazard, but visitors should be aware that such dustings at areas around the Kīlauea summit are possible.
The Hawaiian Volcano Observatory (HVO) continues to closely monitor Kīlauea volcano.
HVO will continue to issue daily Kīlauea volcano updates until further notice. Additional messages will be issued as needed.
Kīlauea activity summary also available by phone: (808) 967-8862
Kīlauea webcam images: https://www.usgs.gov/volcanoes/kilauea/webcams
Kīlauea photos/video: https://www.usgs.gov/volcanoes/kilauea/photo-and-video-chronology
Kīlauea lava-flow maps: https://www.usgs.gov/volcanoes/kilauea/maps
Kīlauea FAQs: https://www.usgs.gov/volcanoes/kilauea/faqs
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 Hawaiʻi and American Samoa.
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Summary of volcanic hazards from eruptions: https://www.usgs.gov/observatories/hvo/hazards
Recent earthquakes in Hawaiʻi (map and list): https://www.usgs.gov/observatories/hvo
Explanation of Volcano Alert Levels and Aviation Color Codes: https://www.usgs.gov/programs/VHP/volcanic-alert-levels-characterize-conditions-us-volcanoes