Presenter: Hugh Roarty (Rutgers University)

Description:
Ocean models play a large role in helping us to understand the ocean’s impact on climate and weather.  Ocean models can also provide information on to mariners to help them in the pilotage of their vessel.  The Deleware Bay Operational Forecast System (DBOFS) provides nowcasts and forecasts of water levels, currents, water temperature and salinity.   A High Frequency radar station was installed in Lewes Delaware in 2021 that dramatically increased the coverage inside Delaware Bay.  Two months of surface current data from the HF radar network were utilized to validate the surface current measurements from the NOAA Operational Forecast System model for Delaware Bay.   The HF radar surface current measurements showed that the model showed good skill in estimating the phase of the currents but underestimated the speed by 50%.  Also, the HF radar measurements highlighted eddies and complex flow regimes that were not represented in the model.   One of the first operational HF radars was deployed in Delaware Bay in 1984.  The deployment captured a weak gyre that forms at the mouth of the bay at slack tide.  The HF radar measurements showed that winds can cause significant departures from the norm, a factor that any successful model must include.  It is now 37 years later and the DBOFS model still does not capture some of the essential features of the surface flow for Delaware Bay.  Hopefully through continued measurements by the HF radar network in the area can help improve the skill of the model.