Scientists at the U.S. Geological Survey Hawaiian Volcano Observatory have elevated the Volcano Alert Level for Mauna Loa from normal to advisory. This change in status indicates that the volcano is showing signs of unrest that are above known background levels, but it does not mean that a Mauna Loa eruption is imminent or certain. HVO’s seismic stations recorded elevated rates of shallow, small-magnitude earthquakes beneath the summit, upper Southwest Rift Zone, and west flank of Mauna Loa for at least the past year. During this same time, HVO monitoring instruments have measured ground deformation on Mauna Loa that is consistent with recharge of the volcano’s shallow magma storage system. Together, these observations indicate that Mauna Loa is no longer at a background level of activity.

Based on these changes in activity, and in accordance with the USGS Volcanic Activity Alert-Notification System, HVO raised the Volcano Alert Level for Mauna Loa to advisory and the Aviation Color Code to yellow. The Volcano Alert Level is a four-tiered system that uses the terms Normal (background levels), Advisory, Watch, and Warning (highest threat) to inform the public about a volcano’s status. These alert levels are issued in conjunction with Aviation Color Codes, which provide information about volcanic-ash hazards to the aviation industry. The codes are Green (background), Yellow, Orange, and Red (eruption imminent). FULL REPORT