MESOSCALE REPRODUCIBILITY IN AN ASSIMILATIVE OCEANIC DOWNSCALING MODEL USING A 3-D STRATIFICATION ESTIMATE BASED ON SATELLITE ALTIMETRY AND ARGO FLOAT DATA

Abstract

 The JCOPE2-ROMS downscaling oceanic modeling system improves mesoscale reproducibility by introducing a simple restoration to data which we call “TS (temperature and salinity) nudging”, where the prognostic temperature and salinity fields are weakly nudged four-dimensionally towards the assimilative JCOPE2 reanalysis (Uchiyama et al., 2012). However, there is not always an accurate reanalysis for assimilative oceanic downscaling models, and therefore alternative dataset should be prepared. Takano et al. (2009) proposed an empirical method to estimate 3-D thermal structure from the near real-time AVISO altimetry data along with the ARGO float profiling data. We view the derived empirical TS data (referred to as TUMSAT-TS) as a candidate for assimilation. A synoptic forward modeling of the JCOPE2-ROMS downscaling system is thus conducted to explore usability of this empirical TS dataset by carrying out with the TS nudging towards the TUMSAT-TS.