@Article{LimaPezzPennTana:2019:InOcMo,
               author = "Lima, Leonardo Nascimento and Pezzi, Luciano Ponzi and Penny, 
                         Stephen G. and Tanajura, Clemente A. S.",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {University of 
                         Maryland} and {Universidade Federal da Bahia (UFBA)}",
                title = "An investigation of ocean model uncertainties through ensemble 
                         forecast experiments in the Southwest Atlantic Ocean",
              journal = "Journal of Geophysical Research: Oceans",
                 year = "2019",
               volume = "124",
               number = "1",
                pages = "432--452",
                month = "Jan.",
             abstract = "cean general circulation models even with realistic behavior still 
                         incorporate large uncertainties from external forcing. This study 
                         involves the realization of ensemble experiments using a regional 
                         model configured for the Southwest Atlantic Ocean to investigate 
                         uncertainties derived from the external forcing such as the 
                         atmosphere and bathymetry. The investigation is based on 
                         perturbing atmospheric surface fluxes and bathymetry through a 
                         series of ensemble experiments. The results showed a strong 
                         influence of the South Atlantic Convergence Zone on the underlying 
                         ocean, 7days after initialization. In this ocean region, 
                         precipitation and radiation flux perturbations notably impacted 
                         the sea surface salinity and sea surface temperature, by producing 
                         values of ensemble spread that exceeded 0.08 and 0.2 degrees C, 
                         respectively. Wind perturbations extended the impact on currents 
                         at surface, with the spread exceeding 0.1m/s. The ocean responded 
                         faster to the bathymetric perturbations especially in shallow 
                         waters, where the dynamics are largely dominated by barotropic 
                         processes. Ensemble spread was the largest within the thermocline 
                         layer and in ocean frontal regions after a few months, but by this 
                         time, the impact on the modeled ocean obtained from either 
                         atmospheric or bathymetric perturbations was quite similar, with 
                         the internal dynamics dominating over time. In the vertical, the 
                         sea surface temperature exhibited high correlation with the 
                         subsurface temperature of the shallowest model levels within the 
                         mixed layer. Horizontal error correlations exhibited strong flow 
                         dependence at specific points on the Brazil and Malvinas Currents. 
                         This analysis will be the basis for future experiments using 
                         ensemble-based data assimilation in the Southwest Atlantic Ocean. 
                         Plain Language Summary The numerical models are powerful tools to 
                         provide knowledge about the ocean state concerning currents 
                         eddies, meanders, and other ocean dynamic and thermodynamic 
                         processes on a range of temporal and spatial scales. An accurate 
                         numerical model makes possible to get a tridimensional ocean 
                         representation with some confidence during time. Even though the 
                         ocean numerical models have been incorporating improvements, 
                         mainly due to a growing evolution of the computational resources, 
                         they are still somewhat limited and bring uncertainties on their 
                         simulations due many reasons that are related to the applied 
                         physical parameterization, atmospheric forcing, bathymetry, and 
                         some other issues. It is crucial to investigate and to know these 
                         uncertainties. This study goes further on the uncertainty 
                         investigations in order to create the basis (prior step) for an 
                         ensemble-based data assimilation system for the Southwest Atlantic 
                         Ocean. Our results indicated that uncertainty in wind forcing 
                         plays a major role in the determination of uncertainty in the 
                         ocean state. Compared to atmospheric forcing, the uncertainty in 
                         bathymetry produced a larger impact on the ocean representation, 
                         especially in shallow waters, though this may be in part due to 
                         excited waves at the initial time.",
                  doi = "10.1029/2018JC013919",
                  url = "http://dx.doi.org/10.1029/2018JC013919",
                 issn = "2169-9275",
             language = "en",
           targetfile = "lima_investigation.pdf",
        urlaccessdate = "12 maio 2024"
}