May 23, 2023 — Mauna Loa GPS Campaign

Hawaiian Volcano Observatory geophysicists are performing the annual GPS survey of Mauna Loa. Most Mauna Loa GPS campaign survey sites have been occupied every year since 1996, whereas less active volcanoes Hualālai and Haleakalā are surveyed every 3–5 years. USGS image by A. Ellis.