Impact of Glider Data Assimilation on the Global Ocean Forecasting System during the 2018 Hurricane Season

Accurate ocean initial conditions are necessary to improve hurricane intensity forecast. We assessed qualitatively the impact of glider data assimilation on the Global Ocean Forecasting System (GOFS 3.1), which provides the initial conditions to the NOAA hurricane forecasting models. For this assessment we used temperature data from two gliders that were within the range of influence of hurricane Michael and Florence. We conclude that the assimilation of glider data in GOFS 3.1 was crucial to improve the pre-storm vertical stratification during Michael. However, the assimilation frequency in the current setup, once a day, was insufficient to capture the rapid cooling of the surface layer. During Florence, GOFS 3.1 did not predict the evolution of the sea surface temperature because the model did not capture the extend of the MAB cold pool.