To understand the complex "plumbing" beneath active volcanic lave lakes and determine the amount of lava flowing from them, Luke Flynn of the University of Hawaii has been using time series of Landsat images. Much of his work has focused on the persistence of volcanic eruptions at Hawaii's Kilauea volcano, which has been continually erupting since 1983. Another objective of Flynn's research - and one critical to many residents of Hawaii - is to map active lava flows and provide advance warning to public safety officials about these natural hazards.
Flynn and other volcanologists have been using remote-sensing data from the geostationary GOES satellite to monitor volcanic eruptions in remote areas in real time. The higher resolution of Landsat data (30 meters as compared to 4 kilometers for GOES) can produce maps of lava flows with pinpoint accuracy, according to Flynn. With these maps researchers can study the evolution of individual eruptions while they are taking place.
With Landsat observations of the heat emitted during eruptions, Flynn can distinguish active lava flows from older flows that have already begun to cool. With this data, Flynn's colleague Andrew Harris is generating estimates of the amount of lava erupting onto the surface. Using similar Landsat data, Flynn produces maps of the leading edges of wildfires.
Flynn and Harris have also been working with Landsat data of active volcanic lava lakes around the world. In addition to their work in Hawaii, they are studying long-term observations of eruptions in Mexico (Popocatepetl) and Guatemala (Santaguito and Pacaya). Once they have compiled extensive observations of an individual volcano, they create a database of areas on the volcano that are most prone to lava flow hazards. Flynn plans to produce even higher resolution maps of active lava flows (15 m) with Landsat 7.
Flynn plans to collect Landsat 7 data at a ground station in Hawaii as the satellite passes over the state. He plans to produce new Landsat 7 volcano (and wildfire) hazard maps for the State of Hawaii every 8 days.
Figure 14.1 Landsat 7 and Land-based Views of Two Guatamalan Volcanoes.