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.
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Last Update: April 9, 2001
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