Abstract
The motivation and objective of the EarthScope Transportable Array (TA)
is to record earthquake signals and image the structure of the North
American plate, however the observations collected by this National
Science Foundation funded project have enabled unanticipated
discoveries, innovative data analysis techniques, and ongoing
investigations across many disciplines in the Earth and space sciences.
The Transportable Array utilized a survey approach to collect data in
which high-quality stations were systematically installed in a dense
geospatial grid. From the very beginning of the deployment, this
strategy allowed for data-driven discovery, such as using seismic data
to map out extensive travel time curves for acoustic waves in the
atmosphere (Hedlin et al., 2010). While the emplacement of the seismic
sensors was kept uniform along with the core components for power and
communications, the Transportable Array station design evolved over time
to include additional barometric pressure and infrasound sensors and,
eventually, meteorological sensors measuring external temperature, wind,
and precipitation. As the array rolled across the Lower 48 and the TA
became more recognized outside of seismology, collaborations were forged
and strengthened with researchers in the infrasound and meteorological
communities. Along with standard approaches using direct measurements,
inventive techniques were used to apply environmental data for observing
tectonic phenomena as well as applying seismic data for observing
environmental phenomena. The value of integrated scientific
infrastructure became even more apparent with the Transportable Array
deployment in Alaska and western Canada, with autonomous and telemetered
stations occupying sites within large swaths of previously unmonitored
and inaccessible terrain. The majority of Alaska TA stations collect
weather data and a subset also include a detached soil temperature
probe. As a result, data collected by the Alaska Transportable Array
have been used to observe throughout the ‘spheres: the lithosphere
(earthquakes, volcanoes, landslides), the cryosphere (sea ice), the
hydrosphere (precipitation, fire preparation), the atmosphere and
biosphere (weather forecasting, storm systems, bolides), and even into
the magnetosphere (space weather).