Mauna Loa is Earth's largest active volcano and covers just over half of the Island of Hawaiʻi. It erupted most recently in 1984 and it will erupt again. This page provides resources to help you understand Mauna Loa eruption hazards and develop an emergency plan.
Hawaiʻi Volcanoes National Park Information:
https://www.nps.gov/havo/index.htm
County of Hawaiʻi Civil Defense Agency:
https://hawaii-county-volcano-hazards-hawaiicountygis.hub.arcgis.com/
What can you do before a future Mauna Loa eruption?
Learn the Hazards
Hazards associated with Mauna Loa eruptions include:
- Large and fast-moving lava flows
- Volcanic air pollution (VOG)
- Fine rock particles downwind
- Damaging earthquakes
- Ground cracks and fissures
- Local tsunami in coastal areas
Learn more on the HVO volcanic hazards webpage: https://www.usgs.gov/observatories/hvo/hazards
See the geonarrative: Mauna Loa: Preparing for the next eruption of Earth's largest active volcano.
Prepare
- Assess how a Mauna Loa eruption could potentially impact you based on where you and your family live, work, and commute.
- Identify which Mauna Loa lava flow inundation zone and lava flow hazard zone you live in: https://hawaii-county-volcano-hazards-hawaiicountygis.hub.arcgis.com/
- Gather emergency supplies and important documents. Create an emergency plan and share it with your friends and family. More information at: https://www.ready.gov/plan
Stay Informed
Official sources of information:
- USGS Hawaiian Volcano Observatory - subscribe to receive message about volcanic activity in Hawaii via the USGS Volcano Notification Service: https://volcanoes.usgs.gov/vns2/
- County of Hawaiʻi Civil Defense Agency - subscribe to receive County of Hawaiʻi Alerts and Notifications: https://member.everbridge.net/index/371914103062563#/signup
What can you do during a future Mauna Loa eruption?
- Get information from official sources
- Implement the emergency plan that you and your family have developed
- Heed County of Hawaiʻi guidance and evacuate if necessary
Mauna Loa reference maps

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