Data assimilation of temperature and salinity profiles in the Adriatic Sea regional model

Abstract

Temperature and salinity data collected during the October 2002- October 2003 period have been assimilated into a version of the Princeton Ocean Model implemented over the entire Adriatic Sea. The scheme used is SOFA (System for Ocean Analysis and Forecast, DE MEY & BENKIRAN, 2002) and this is the first coastal application of this scheme. The CTD data were collected in 4 coastal areas (Emilia – Romagna Coastal strip, the Gulf of Trieste, the Rovinj and Pelješac-Vis-Drvenik coastal strips) while temperature profiles were acquired with XBT in the southern Adriatic Sea deep ocean areas. The analysis skill scores are examined in order to evaluate the assimilation performance. The results of the assimilation are first compared with independent analyses of satellite Sea Surface Temperature (SST) and it is found that assimilation of profiles improves the SST model estimate. Furthermore, the Root Mean Square (RMS) difference between model and temperature and salinity profiles before data insertion is analysed. The range of RMS temperature error is less than 1 0C for the entire area and decreases with time, indicating a positive impact of the assimilation. The RMS of salinity is less than 1 psu and it also shows a decreasing trend during the assimilation period.