Mauna Loa 2022 summit and Northeast Rift Zone eruption — December 10, 2022 thermal map

In the late evening of November 27, 2022, an effusive eruption began inside Moku'aweoweo caldera at the summit of Mauna Loa volcano. Within a few hours, lava had covered most of the caldera floor, and several fissures just outside caldera sent short lava flows up to 3 kilometers (2 miles) to the southwest. Later in the morning of November 28, summit effusion ceased and the eruption moved into the volcano's Northeast Rift Zone. Several rift zone fissures were initially active, but by November 30 effusion had focused at a vent known as fissure 3. For another 10 days, fissure 3 fountained and fed lava flows that eventually stretched 18 kilometers (11 miles) to the north, threatening but not reaching the Daniel K. Inouye Highway across the island's interior. Effusion from fissure 3 began declining overnight December 7–8 and ceased on December 10, by which time the eruption had covered approximately 36 square kilometers (14 square miles) of Mauna Loa with new lava. In this report, the authors have sought to chronicle this sequence of events using geospatial data in the form of an Esri file geodatabase, Esri shapefiles, and Google Earth KMZs, as well as rapid-response orthomosaic and thermal map rasters.