The urban ocean observatory – Urban ocean observations and forecasting in the New York Harbor

The Hudson-Raritan Estuary and the New Jersey Atlantic Ocean shoreline are densely-populated regions that provide significant economic, environmental, and recreational benefits to the States of New York and New Jersey, and to the US nation. Issues confronting the region include safe navigation and maritime security, water quality concerns, and coastal beach erosion and flooding. Since 1998, Stevens has been developing a network of operational coastal ocean and estuary sensors that provide real-time observations of weather and ocean conditions throughout the region. As the network has expanded, and experience has been gained in the operation of the sensors and in the specialized needs of the array of data users, the system has evolved significantly.

The New York Harbor Observation and Prediction System, NYHOPS, has been operational since the beginning of 2004. The primary goal of the established system is to provide 48hr hydrodynamic forecasts of sea level, salinity, temperature, three-dimensional currents through a versatile interface accessible through the internet to the general public at www.stevens.edu/maritimeforecast. The diverse user base of NYHOPS ranges from Office of Naval Research, NJ Department of Transportation, and FEMA personnel to recreational boaters in need of knowing the past, present, and future hour-to-hour water circulation and hydrodynamic environment in the New York / New Jersey Harbor Estuary and its vicinity. New products – for example wave forecasts, chromophoric dissolved organic matter (CDOM) tracing, CODAR currents, etc. – have been added since 2004, along with several code enhancements like wetting/drying of tidal flats.

NYHOPS utilizes a network of underwater sensors installed and operated by Stevens Institute of Technology, and an EDUCATE (External Data Uninterrupted Cashed Acquisition and Transfer Effectiveness) protocol that taps into external databases and federal agency forecasts, to create the input forcing to a three-dimensional hydrodynamic forecast model (ECOMSED, of the POM family of models). A high-resolution curvilinear model grid is used to encompass the entire Hudson-Raritan (New York/New Jersey Harbor) Estuary, the Long Island Sound, and the New Jersey and Long Island coastal ocean. The horizontal resolution of the grid ranges from an average of approximately 7.5km at the open ocean boundary to less than 50m in several parts of the NY/NJ Harbor Estuary with a vertical resolution of 10 sigma layers. The model simulates the marine environment in response to meteorological conditions, freshwater and thermal inflows, tides, and baroclinicity (density-driven forces) at the open boundaries. The enhancement of model accuracy is accomplished through the assimilation of observations