Collaborative Instrumentation: COCONet (Continuously Operating Caribbean GPS Observational Network) An Infrastructure Proposal for a Multi-hazard Tectonic and Weather Observatory

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This collaborative grant to UNAVCO, Inc., an EAR supported national geodetic support Facility (EAR-0735156), and the University Corporation for Atmospheric Research (UCAR), an AGS supported consortium that manages the National Center for Atmospheric Research Facilities (NCAR), supports a five year planned development of a plate-scale integrated geodetic and atmospheric/regional climate observational system in the pan-Caribbean region. A goal of the Continuously Operating Caribbean GPS Observational Network (COCONet) is to add 50 new semi-permanently monumented, continuously operating, Global Positioning Satellite (cGPS) stations spanning multiple Caribbean and Caribbean bordering nations. COCONet goals also call for the integration of GPS data from up to 50 existing stations operating in the Caribbean. The new cGPS stations will, in some cases, be co-located with existing tide gauges, thus supporting studies of sea level change in response to current global warming, and will be mated with surface meteorological observational equipment (Metpacks) to significantly expand spatiotemporal geodetic and atmospheric observational infrastructure in a region of complex tectonics with substantial earthquake, tsunami, volcanic, tropical storm and hurricane, flooding and landslide hazards. COCONet will provide a backbone fiducial and meteorologic observational network and COCONet data and data products that will be freely available through the UNAVCO archive will be available to serve a broad range of basic tectonic and atmospheric research investigations and enable observations of immediate relevance for advancing understanding, mitigating and perhaps predicting regional geohazards. Some specific questions that COCONet data could help to address include: 1) How rigid is the Caribbean plate?; 2) What are the slip rates along active faults that bound the Caribbean plate?; 3) How is stress released at convergent plate boundaries and how is stress transferred across plate boundaries?; and 4) How can we better understand and assess hazards in the Caribbean and Central American regions? Atmospheric questions that could be advanced by proposed GPS meteorological determinations and surface measurements of atmospheric physical properties include: 1) How sensitive is tropospheric water vapor content to changes in sea surface temperatures?; and 2) How does the distribution of precipitable water vapor across the Caribbean region influence the genesis, intensification and vectoring of tropical storms and hurricanes? COCONet data will flow via the EarthScope Plate Boundary Observatory (PBO) data management system and be available via the Web-accessible UNAVCO data archive. Low-latency data telemetry will be via cellular modem or through VSAT satellite communications to the PBO Network Operations Center in Boulder, Colorado. These data will be processed into derived geodetic products, including combined GPS station position and velocity estimates, simplified position time series and velocity field estimates in multiple formats, at the existing PBO GPS Analysis Centers at Central Washington University and New Mexico Tech and the Analysis Center Coordinator at MIT. In addition, UCAR will estimate tropospheric precipitable water vapor (PV) every 30 minutes from observations of GPS radio frequency signal propagation delays along the path length between the satellite transmitter and the receiver coupled with concurrent surface measurement of barometric pressure. The PV observations will feed into operational numerical weather models run several times per day. The project will engage Caribbean researchers, their students and governmental agency representatives with the goal of empowering these nations to utilize COCONet data for both scientific and socioeconomic purposes. Real-time data from COCONet will be made available to the International GNSS Service (IGS) to help densify GPS observations in a region of the globe with few existing real-time data streams and thereby improve GPS satellite orbit calculations and help to refine the international terrestrial reference frame (ITRF).