Internal Integrated Surveillance Instrumentation Real-time Data Received from Mount Erebus Volcano,antarctica

and eruptive volcano processes involve complex interactions of multi-phase fluids with the solid Earth and the atmosphere, and produce diverse geochemical, visible, thermal, elastic, and anelastic effects. Multidisciplinary experimental agendas are increasingly being employed to meet the challenge of understanding active volcanoes and their hazards [e.g., Ripepe et al., 2002; Wallace et al., 2003]. Mount Erebus is a large (3794 m) stratovolcano that forms the centerpiece of Ross Island,Antarctica, the site of the principal U.S.(McMurdo) and New Zealand (Scott) Antarctic bases.With an elevation of 3794 m and a volume of ~1670 km 3 , Erebus offers exceptional opportunities for extended study of volcano processes because of its persistent, low-level, strombolian activity (Volcano Explosivity Index 0-1) and exposed summit magma reservoir (manifested as a long-lived phonolitic lava lake). Key scientific questions include linking conduit processes to near-field deformations [ 1992], and effects on Antarctic atmospheric and ice geochemistry [e.g., Zre-da-Gostynska et al., 1997]. The close proximity of Erebus (35 km) to McMurdo, and its characteristic dry, windy, cold,and high-elevation Antarctic environment, make the volcano a convenient test bed for the general development of volcano surveillance and other instrumentation under extreme conditions. of a five-station Integrated Surveillance Instru-mentation (ISI) network of sensors,data acquisition , and telemetry hardware (Figures 1 and 2). ISI stations are designed to deliver real-time, year-round data streams to McMurdo, NMT, and worldwide via the Internet, while augmenting a pre-existing, year-round network of short-period, FM-telemetered seismic stations and continuous single-frequency Global Positioning System (GPS) receivers. The primary objectives are to acquire diverse multi-year observations about the physical conditions of Erebus, and to develop instru-mentation for general multidisciplinary volcano data collection in remote and hostile environments . An important objective was to integrate the geodetic data from a dual-frequency GPS receiver into the seismic data stream with a minimum of redundant hardware.The integration of geodesy with seismology is essential to understanding the full spectrum of deforma-tional processes in volcanic and tectonic environments as,for example, in the EarthScope program [van der Vink,2002]. ISI instrumentation consists of a broadband seismometer, digitizer, dual-frequency GPS receiver, and 9000-MHz spread-spectrum radio modem.Additional sensors deployed at selected stations include infrasonic microphones,infrared radiometers,tiltmeters,gas sensors,and weather instruments (temperature,wind speed/direction, humidity,and barometric pressure). Component and battery temperatures, current, and voltage are further monitored to assess overall system performance.A telemetered, time-stamped video camera allows observations of lava lake and other vent activity. Station design was dictated by scientific goals, environmental robust-ness,helicopter transportability, and …