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Hawaiian Volcano Update: Kīlauea & Maunaloa Quietly Inflating

3:03 AM · Jul 21, 2023

Following the skirting passage of Tropical Storm Calvin, monitoring signals on Kīlauea and Maunaloa are returning to normal with no lasting impact on either volcano. The long-term pattern of summit inflation on both mountains has resumed, caused by the underground build-up of magma. Independently in both cases, the build-up lacks the seismicity that would be expected ahead of an eruption, though GPS signals around Kīlauea's summit continue to show significant uplift since the end of last month's eruption. This suggests a progression back towards a state of heightened unrest, though its timing is difficult to predict. A superficial comparison between Kīlauea's recent summit eruptions reveals a change in pattern in June 2023, mostly a result of its short duration, but further muddles the predictability of future events. Reviewing last month's activity further, its progression and details are still quite similar to the other recent summit eruptions, but lacking the drawn-out end stage of dwindling lava production. Maunaloa is still quiet on its surface as magma continues the normal process of refilling its summit reservoir, with no significant changes to report. However, as an example of this steadily ongoing process, the near-summit GPS station at Pohaku Hanalei at 12140' elevation shows nearly 5 cm or 2 inches of vertical uplift since the end of the eruption in December 2022, with the rate of ascent slowing in recent months. Our live presentation reviews the recent changes using monitoring data, imagery and reports courtesy of the USGS Hawaiian Volcano Observatory, and time lapse videos derived therefrom. We annotate the presentation on-screen, and discuss live viewer questions as usual.