Volcano Watch: Campaign season is here! Another way HVO tracks changes on Hawaiian volcanoes

  • On the west side of Mauna Loa summit, a campaign GPS (center-right) measures its location for a period of 2–3 days. This site has been occupied every year by helicopter since 1994. Mauna Kea, Hualalai and Haleakala can be seen in the distance. (USGS photo by S. Conway)

Geodetic surveys measure the change in shape of our volcanoes due to changes in magma supply and storage. The USGS Hawaiian Volcano Observatory has a long history of using many different types of instruments and technologies over the decades to detect these changes.