Hawaiian Volcano Update: Kīlauea's Eruption Wanes During Deflation & Rainfall

Kīlauea's summit eruption was much reduced this past week, coincident with a large deflation of the ground surface as well as with tremendous rainfall which produced over 1 foot or 0.3 meters of rainfall. Lava only remains weakly active within the western basin, with no output from the central or eastern vents, but is “expected to resume when the summit re-inflates to the levels observed in the prior week” according to the USGS Hawaiian Volcano Observatory. A similar pattern of large outbursts interrupted by near- or full-pauses was evident one year ago during the 2021-22 eruption, driven by subsurface adjustments within the magmatic plumbing. While heavy rainfall has affected monitoring signals to varying degrees, a similar “bottom-up” process is the likely culprit in the surface change. Previous cloud bursts have actually shown the ability to induce spattering and overturning with the summit lava lake, however only produced a minor drop in the lava level of about 1 yard or meter through its “top down” effect. Other studies have modeled the effect of rainfall on the pressure state within the volcano, which exists but is comparable to the forces exerted by tidal effects, both of which are much smaller than the forces driving volcanic processes. The weather and reduction in activity have made for sub-optimal viewing within Hawaiʻi Volcanoes National Park, but have also cleared the air of the persistent vog that remains the primary eruptive hazard for island residents. All lava activity remains contained within Kīlauea's summit crater of Halemaʻumaʻu, with no indications of unusual activity in either rift zone and no increased threat to people. As usual, we review the recent changes in the eruption using webcam timelapses, videos, and reports courtesy of the USGS Hawaiian Volcano Observatory, annotate the presentation on-screen, and discuss live viewer questions. Maunaloa's recent lava flows continue to cool, steaming in the recent rain, with no further monitoring changes to report. https://youtube.com/live/_zJqFFlUlBs