Real-Time Telemetry Options for Ocean Observing Systems

Abstract: Ocean observing systems provide a means to monitor oceanic variables on a variety of temporal and spatial scales. Data from ocean observing systems are most useful when they are collected in real-time; real-time data allow the detection of important events as they occur. Various real-time telemetry options exist for transferring data from sea to shore and from the subsurface to the surface. We survey these telemetry options to highlight the research problems associated with subsea to surface to shore networking and include a comparison of existing real-time technologies for three specific ocean observing system network topologies with respect to data transmission rates, power requirements, and cost. We conclude that cellular technology may prove to be the best means for sea to shore transmission in nearshore regions whereas Iridium satellite communications are ideal for locations not covered by cellular service. Further advances in cabled mooring lines and inductive and acoustic modem technologies will make these more attractive options for subsurface to surface data transmissions. Ocean observing systems provide a means to monitor oceanic variables on a variety of temporal and spatial scales. Data from ocean observing systems are most useful when they are collected in real-time; real-time data allow the detection of important events as they occur. Various real-time telemetry options exist for transferring data from sea to shore and from the subsurface to the surface. We survey these telemetry options to highlight the research problems associated with subsea to surface to shore networking and include a comparison of existing real-time technologies for three specific ocean observing system network topologies with respect to data transmission rates, power requirements, and cost. We conclude that cellular technology may prove to be the best means for sea to shore transmission in nearshore regions whereas Iridium satellite communications are ideal for locations not covered by cellular service. Further advances in cabled mooring lines and inductive and acoustic modem technologies will make these more attractive options for subsurface to surface data transmissions.