Systematic observations of Volcán Turrialba, Costa Rica, with small unmanned aircraft and aerostats (UAVs): the Costa Rican Airborne Research and Technology Applications (CARTA) missions
Thursday, 18 December 2014
For several years, the University of Costa Rica, NASA Centers (e.g., JPL, ARC, GSFC/WFF, GRC) & NASA contractors-partners have made regular in situ measurements of aerosols & gases at Turrialba Volcano in Costa Rica, with aerostats (e.g., tethered balloons & kites), & free-flying fixed wing UAVs (e.g., Dragon Eye, Vector Wing 100, DELTA 150), at altitudes up to 12.5Kft ASL within 5km of the summit. Onboard instruments included gas detectors (e.g., SO2, CO2), visible & thermal IR cameras, air samplers, temperature pressure & humidity sensors, particle counters, & a nephelometer. Deployments are timed to support bimonthly overflights of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) onboard the NASA Terra satellite (26 deployments to date). In situ observations of dilute plume SO2 concentrations (~1-20ppmv), plume dimensions, and associated temperature, pressure, & humidity profiles, validate detailed radiative transfer-based SO2 retrievals, as well as archive-wide ASTER band-ratio SO2 algorithms. Our recent UAV-based CO2 observations confirm high concentrations (e.g., ~3000ppmv max at summit jet), with 1000-1500ppmv flank values, and essentially global background CO2 levels (400ppmv) over distal surroundings. Transient Turrialba He detections (up to 20ppmv) were obtained with a small (~10kg) airborne mass spectrometer on a light aircraft—a UAV version (~3kg) will deploy there soon on the UCR DELTA 500. Thus, these platforms, though small (most payloads <500gm), can perform valuable systematic measurements of potential eruption hazards, as well as of volcano processes. Because they are economical, flexible, and effective, such platforms promise unprecedented capabilities for researchers and responders throughout Central and South America, undertaking volcanic data acquisitions uniquely suited to such small aircraft in close proximity to known hazards, or that were previously only available using full-sized manned aircraft. This work was carried out, in part, at the Jet Propulsion Laboratory of the California Institute of Technology under NASA contract. We are grateful to the Universidad de Costa Rica, the NASA Airborne Science and Earth Surface & Interior Programs, the Dirección General de Aeronáutica Civil de Costa Rica, and FH Düsseldorf for their support.