USGS Volcano Notice - DOI-USGS-HVO-2023-03-02T10:02:21-08:00

HAWAIIAN VOLCANO OBSERVATORY WEEKLY UPDATE
U.S. Geological Survey
Thursday, March 2, 2023, 8:20 AM HST (Thursday, March 2, 2023, 18:20 UTC)

MAUNA LOA (VNUM #332020)
19°28'30" N 155°36'29" W, Summit Elevation 13681 ft (4170 m)
Current Volcano Alert Level: ADVISORY
Current Aviation Color Code: YELLOW

Activity Summary: Mauna Loa Volcano is not erupting. 

Observations:

There is no active lava within Moku'āweoweo caldera nor along either rift zone, including at the November–December 2022 eruption site. Satellite imagery shows that the entire 2022 flow field is cooling and no longer active.

Earthquake rates remain low and there is no detectable volcanic tremor—a seismic signal associated with subsurface fluid movement. Deformation rates indicate ongoing inflation somewhat above background levels, but this is not uncommon following eruptions. The Hawaiian Volcano Observatory continues to closely monitor the seismicity and deformation rates at Mauna Loa. We expect additional shallow seismicity and other signs of unrest to precede any future eruption, if one were to occur. 

Sulfur dioxide (SO₂) emission rates are at background levels. Concentrations of sulfur dioxide (SO₂), hydrogen sulfide (H₂S), and carbon dioxide (CO₂), as well as fumarole temperatures, remain low and stable at Sulphur Cone on the upper Southwest Rift Zone. The Hawaii Interagency Vog Information Dashboard has detailed information about vog: https://vog.ivhhn.org/. Forecasts for the dispersion of vog can be found on the VMAP Vog Forecast Dashboard: http://weather.hawaii.edu/vmap/new/. 

The Hawaiian Volcano Observatory will continue to closely monitor Mauna Loa for any changes.  

For more information on current monitoring of Mauna Loa volcano, see: https://www.usgs.gov/volcanoes/mauna-loa/monitoring.

Background:
Mauna Loa is the largest active volcano on our planet, rising gradually to 4,170 meters (13,681 feet) above sea level. Its long submarine flanks descend an additional 5 kilometers (3 miles) below sea level to the ocean floor. The ocean floor directly beneath Mauna Loa is, in turn, depressed by the volcano's great mass another 8 kilometers (5 miles). This places Mauna Loa's summit about 17,000 meters (56,000 feet) above its base. The enormous volcano covers half of the Island of Hawaiʻi and by itself amounts to about 85 percent of all the other Hawaiian Islands combined.

Eruptions typically start at the summit and, within minutes to months of eruption onset, about half of the eruptions migrate into either the Northeast or Southwest Rift Zone. Since its first well-documented eruption in 1843, the volcano has erupted 34 times with intervals between eruptions ranging from months to decades. Mauna Loa last erupted in November–December 2022.

Mauna Loa eruptions tend to produce voluminous, fast-moving lava flows that can impact communities on the east and west sides of the Island of Hawaiʻi. Since the mid-19th century, the city of Hilo in east Hawaiʻi has been threatened by seven Mauna Loa lava flows. Mauna Loa lava flows have reached the south and west coasts of the island eight times: in 1859, 1868, 1887, 1926, 1919, and three times in 1950.

More Information:
Mauna Loa activity summary also available by phone: (808) 967-8866
Mauna Loa webcam images: https://www.usgs.gov/volcanoes/mauna-loa/webcams
Mauna Loa photos/video: https://www.usgs.gov/volcanoes/mauna-loa/photo-and-video-chronology-mauna-loa
Mauna Loa maps: https://www.usgs.gov/volcanoes/mauna-loa/maps
Mauna Loa FAQs: https://www.usgs.gov/volcanoes/mauna-loa/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.

CONTACT INFORMATION:

askHVO@usgs.gov
 

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