Using the Regional Ocean Modelling System (ROMS) to improve the sea surface temperature predictions of the MERCATOR Ocean System

Global models are generally capable of reproducing the observed trends in the globally averaged sea surface temperature (SST). However, the global models do not perform as well on regional scales. Here, we present an ocean forecast system based on the Regional Ocean Modelling System (ROMS), the boundary conditions come from the MERCATOR ocean system for the North Atlantic (1/6 degrees horizontal resolution). The system covers the region of the northwestern Iberian Peninsula with a horizontal resolution of 1/36 degrees, forced with the Weather Research and Forecasting Model (WRF) and the Soil Water Assessment Tool (SWAT). The ocean model results from the regional ocean model are validated using real-time SST and observations from the MeteoGalicia, INTECMAR and Puertos Del Estado real-time observational networks. The validation results reveal that over a one-year period the mean absolute error of the SST is less than 1 degrees C, and several sources of measured data reveal that the errors decrease near the coast. This improvement is related to the inclusion of local forcing not present in the boundary condition model.