May 26, 2023 — Mauna Loa GPS Campaign

Hawaiian Volcano Observatory geophysicists continue performing the annual GPS survey of Mauna Loa. Most Mauna Loa GPS campaign survey sites have been occupied every year since the early 1990s, whereas less active volcanoes Hualālai and Haleakalā are surveyed every 3–5 years.



During the annual Mauna Loa GPS campaign, scientists temporarily deploy a number of GPS instruments at established benchmarks; their recorded positions can be compared with those from previous years to discern subtle patterns of ground deformation associated with volcanic activity. These data augment the permanent, continuously recording GPS instruments in HVO's monitoring network. In this photo, a survey tripod is established over a benchmark near the summit of Mauna Loa. USGS image by A. Ellis.