Wave and current measurements in the Chesapeake Bay

The National Ocean Service of NOAA maintains and operates a Physical Oceanography Real Time System (PORTSO) in the Nation´s major ports, harbors and bays. Environmental parameters such as water levels, currents and a host of other hydrological and meteorological variables are monitored in real time. Wave is another variable that is of increasing interest to the PORTSO users, but has not been included in the routine observation. Improvements in the measurement method and technology are continuously evolving in the PORTSO program. This paper describes a partnership project for wave and current measurements in the Chesapeake Bay. The goals are twofold: to obtain current and wave data to support NOS wave and oil spill trajectory modeling and marsh restoration efforts; and to test new measurement methods and data telemetry technologies. Instruments used include a Triaxys directional wave buoy, and a 1200 and a 600 KHz Acoustic Doppler Current Profilers which measures both currents and waves. Both wave measuring instruments have been validated through laboratory and field tests. The ADCP data are recorded internally and telemetered via underwater modems and line-of-sight radio on a surface buoy. The Triaxys wave buoy wave data are recorded internally and telemetered in real-time via line-of-sight radio and Argos. This paper describes the measurement systems and pre-deployment tests, the first field deployment, and sample result from these activities.