@InProceedings{CamargoPezzHerd:2010:ObNuSt,
               author = "Camargo, Ricardo de and Pezzi, Luciano Ponzi and Herdies, Dirceu 
                         Luis",
          affiliation = "Atmospheric Sciences, Institute of Astronomy, Geophysics and 
                         Atmospheric Sciences of University of S{\~a}o Paulo, S{\~a}o 
                         Paulo, Brazil and {Instituto Nacional de Pesquisas Espaciais 
                         (INPE)} and {Instituto Nacional de Pesquisas Espaciais (INPE)}",
                title = "Observational and numerical studies of SST variability at South 
                         Atlantic using the regional CPTEC oceanic data assimilation system 
                         (R-CODAS)",
                 year = "2010",
         organization = "The Meeting of the Americas.",
            publisher = "AGU",
             keywords = "numerical modeling, ocean data assimilation, reanalysis, ocean 
                         predictability, prediction.",
             abstract = "The Sea Surface Temperature (SST) variability can play a decisive 
                         role on the atmospheric systems evolution either on climate or 
                         weather time scales. There are lots of efforts being applied to 
                         adequately represent SST features and variability, even 
                         considering uncoupled models of both atmosphere and ocean. This 
                         work aims to investigate SST features and variability at South 
                         Atlantic, based on Optimal Interpolation SST version 2 (OISSTv2) 
                         and numerical experiments performed with Regional Ocean Modeling 
                         System (ROMS) with and without data assimilation. This was made 
                         through the use of Regional CPTEC Oceanic Data Assimilation System 
                         (R-CODAS) based on Local Kalman Ensemble Filter Transform (LETKF) 
                         technique. On the observational aspects, space EOFs showed modes 
                         of SST variability at South Atlantic that can be connected to 
                         Equatorial Pacific SST anomalies linked to El-Niņo Southern 
                         Oscilation (ENSO) and also to South Pacific SST variations related 
                         to extratropical signature of Pacific-South America atmospheric 
                         teleconnection patterns (PSA). For the modeling stage, ROMS 
                         simulations were performed in a 1/2 degree resolution grid 
                         covering Tropical and South Atlantic Ocean, using both bulk-fluxes 
                         formulation and NCEP/Reanalysis fluxes, being the latter with heat 
                         and fresh water flux corrections. These numerical results could 
                         show the model sensitivity to atmospheric forcing, mainly over 
                         higher latitudes of Western South Atlantic. Spin-up stages of 20 
                         years with each of those forcing files reached dynamically 
                         balanced fields that were used as initial conditions for long 
                         integrations in the period 1980-2009. Once again, differences 
                         between bulk-formulation and NCEP/Reanalysis fluxes are more 
                         significant over Argentinean shelf than in other regions of the 
                         domain. Despite this fact, both simulations could reasonable 
                         represent SST features and variability, and could be considered 
                         for the data assimilation stage. R-CODAS is still under 
                         development/tuning and preliminary results assimilating only 
                         OISSTv2 data showed that the number of members as well as the 
                         inflation coefficient are key-parameters for the simulations, 
                         reflecting directly on the capacity of the method on assimilating 
                         real data. New analyzed fields after the assimilation cycle were 
                         closer to the reality when compared with no-data-assimilation 
                         results. The next step is the consideration of Sea Surface Height 
                         from satellite data (SSH) as well as ocean profiles to be included 
                         in the assimilation procedure, besides spatial and time analyses 
                         of the numerical fields.",
  conference-location = "Foz do Igua{\c{c}}u",
      conference-year = "8-12 Aug. 2010",
             language = "en",
           targetfile = "Camargo_Observational.pdf",
        urlaccessdate = "15 jun. 2024"
}