Validation of ocean forecasting model data with those obtained from the first transoceanic autonomous underwater vehicles (gliders) missions in the North-East Atlantic basin

Abstract

Autonomous Underwater Vehicles (AUVs), like gliders, can be used to cover long oceanographic missions due to their low battery consuming system. This study uses data from the Challenger Mission, between Ireland and the Canary Islands, from the 14th of May to the 8th of November 2017. It is compared to the ocean models Mercator Global Ocean Model (Mercator) and Copernicus Iberian-Biscay-Irish Regional Ocean Model (IBI), taken from the Copernicus Marine Environment Monitoring Service (CMEMS, http://marine.copernicus.eu), to validate them. The compared variables are temperature, salinity and density. The studied area, located at the North-East Atlantic basin, is a complex dynamic region with several oceanographic processes involved, influenced by climatic phenomena and the Thermohaline Circulation (THC). The comparison between model data and glider data has been done in previous studies, but not with the models used on this study. Salinity data has a higher variation at intermediate waters (500-1000m). Models show lower salinity than glider data on the water column, and higher on the surface. Models’ temperature is generally cooler. In general, models show lower density. Overall, temperature data is more correct than salinity data. We suggest that it would be useful to do some additional studies comparing in situ high resolution glider data and ocean models in order to improve them.