Development of a standalone real-time water level measurement system to support safe navigation along Alaska's arctic coasts

The United States National Oceanic and Atmospheric Administration (NOAA) National Ocean Service (NOS) Center for Operational Oceanographic Products and Services (CO-OPS) is responsible for developing and maintaining the National Water Level Observation Network (NWLON) which consists of over 200 long term observatories throughout all U.S. coasts. CO-OPS continually pursues efforts to identify potential improvements to its observatory network. Many recent studies on global climate change have identified a significant increase in Arctic warming rates. Resulting trends of increased sea ice loss have led to Arctic waterways becoming more accessible during summer seasons. As a result, an increase in maritime transport throughout the region is anticipated for the near future. Presently, Artic waters within the U.S. Exclusive Economic Zone (EEZ) have very few navigational support products and services. NOAA, recognizing the changing conditions, anticipates a growing, critical need for real-time oceanographic and meteorological observations across the region. In support of long term modernization plans, CO-OPS has been working on the design, development, and testing of a standalone, real-time water level measurement system for use in remote Arctic coastal regions with very limited infrastructure. Two types of system designs have been identified, for short and long term applications. Both design types include a bottom mounted pressure gauge for the primary source of water level measurements. The long-term system design involves a cable run from an offshore bottom mounted pressure gauge to a small, shore station. The short term system design includes a surface buoy with satellite telemetry and acoustic modem; and a bottom unit consisting of a conductivity, temperature, pressure sensor and acoustic modem. The buoy based system is intended for real-time communications during ice-free periods. Details of the short-term version system design will be presented along with results from a recent field trial conducted in the lower Chesapeake Bay region near Virginia Beach, Virginia during 2014–2015. Plans for continuing system development and test will be discussed.