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Introduction The Brazilian Oceanographic Modeling and Observation Network (REMO) is a GODAE OceanView member since December 2010. REMO is a consortium formed by the Federal University of Bahia (UFBA), Federal University of Rio de Janeiro (UFRJ), the Brazilian Navy Hydrographic Center (CHM) and the Research and Development Center of the Brazilian-state oil company Petrobras (CENPES) formed in 2008. From 2008 to 2011, the University of São Paulo (USP) and the Federal University of Rio Grande (FURG) were also REMO members. CHM – located in Niterói, Rio de Janeiro - hosts the operational forecasting system. It produces short-range forecasts (5 days) in a daily basis with the Hybrid Coordinate Ocean Model (HYCOM) configured in three different grids (Fig. 1): (i) a large-scale grid over the Atlantic Ocean (78 o S-50 o N, 100 o W-20 o E excluding the Pacific Ocean) with 1/4 o horizontal resolution; (ii) an eddy-resolving grid (46 o S-10 o N, west of 18 o W) focusing on Metarea V (36 o S-7 o N, west of 20 o W) with 1/12 o horizontal resolution; and (iii) a high- resolution grid off the Brazilian S-SE shore (35 o S-12 o S, 54 o W-32 o W) with 1/24 o resolution and tides. All grids use 21 vertical layers. The forecasts are forced with the NCEP Global Forecasting System (GFS) for the large-scale grid and with the German COSMO with 10 km resolution for the other two grids. The Ensemble Optimal Interpolation (EnOI) scheme is used operationally in CHM since February 2014 to assimilate only sea surface temperature (SST) analysis and gridded sea level anomalies (SLA) data from AVISO-CLS. Assimilation is performed twice a week, on Tuesdays and Fridays. A more complete data assimilation, the REMO Ocean Data Assimilation System (RODAS), is under consolidation. It is based on a multivariate EnOI scheme and is capable of assimilating SST analysis, temperature (T) and salinity (S) profiles from Argo, and along-track or gridded SLA data from satellites with or without superobservation. The scheme is mainly based on the work by Evensen (Ocean Dyn. 2003), Oke and Sakov (J. Oceanic Atmos. Tech. 2008), Xie and Zhu (Ocean Modell. 2010) and Mignac et al. (Ocean Sci. 2015). The inclusion of vertical T/S profiles from Argo in the operational system is planned for the first semester of 2016. Clemente A. S. TANAJURA on behalf of the REMO team (www.rederemo.org) Physics Institute & Center for Research in Geophsyics and Geology (CPGG), Federal University of Bahia (UFBA), Salvador, Brazil VI GODAE OceanView Science Team Meeting, Sydney, 2-6 November, 2015 Report from the Brazilian Forecasting System The Oceanographic Modeling and Observation Network (REMO) 24 h-Forecast Evaluation for SLA, SST and Argo T/S 2015 Highlights Simplified OI (2013) versus EnOI (2014) SLA is compared with AVISO, SST with OSTIA and vertical T/S profiles with Argo Table 1. CLS Products under contract with CHM under REMO Data Assimilation The RODAS version running operationally in CHM started using OSTIA SST from the UK Met Office and SLA data from Atobá-CLS on December 2, 2014. Before this, sea surface height (SSH) and SST from the HYCOM+NCODA system were employed to constrain the model initial condition. The Atobá-CLS SLA data were the result of a contract between CHM and CLS under REMO (see Table 1 with the products). Along- track data from DUACS/AVISO are filtered and used today for the large-scale grid. The Atobá-CLS gridded data is used in the mesoscale and high resolution grids. The system realizes a 2-D assimilation of SLA and the Cooper and Haines scheme is used to modify the model layer thicknesses and velocities. The assimilation of SST imposes corrections in the model layer thicknesses, velocities and temperature (salinity is diagnosed). Observations The Brazilian Navy oceanographic vessel Antares deployed two REMO buoys in March 2015. They are equipped with sensors to measure: (i) winds at 3 m; (ii) air temperature at 2 m; (iii) sea level pressure; (iv) surface relative humidity; (v) wave height, peak period and direction at the surface; (vi) currents up to 100 m; and (vii) water temperature at each 10 m up to 100 m depth. The majority of those data will be transmitted to the GTS (Global Transmission System) and will have free public access. Those data will soon be available in REMO's web page at www.rederemo.org. The buoys are close to Cabo Frio, Rio de Janeiro. They are placed over a 300 m (CF1) and a 2000 m (CF2) water layer at 23,7703 o S, 41,6106 o W (CF1) and -24.1903 o S, 41.3414 o W (CF2). The physical structure of the buoy, including the transmission hardware, was made in Brazil. All sensors were made abroad. REMO is also a GHRSST member and is producing SST analysis with 0.05 o resolution for the South Atlantic. The product is available at ftp://podaac.jpl.nasa.gov since September 2014. The SST analysis is under evaluation and improvement (e.g., to include in situ data) in order to be used in the operational system. Figure 1. The nested grid system employed operationally today in CHM. The large-scale domain is resolved with a 1/4 o resolution grid, the Metarea V with a 1/12 o grid and the S- SW Atlantic with a 1/24 o grid. Along-track Products (L3) Gridded (L4) Jason-2 Cryosat-2 SaralAltika merged Area_V0 7 km 7 km 7 km - Area_V1 7 km 7 km 7 km 1/8 o Area_V2 1.4 km 1.4 km 1.4 km 1/12 o Figure 2. Brazilian National Buoy Array has REMO collaboration. The use of EnOI without the vertical profiles of T/S is producing an increase in the erros of temperature and salinity. RODAS is able to constrain the model with Argo T/S data as demonstrated by the result below in the 1/12 o grid in which SST, SLA and Argo T/S were assimilated for 4 years. RODAS RODAS FREE FREE 2016 Plans • Assimilate Argo T/S operationally • Test new grids with higher resolution and larger domain • Test assimilation of XBT data • Deploy one more moored buoy • Produce SST analysis including in situ data Observation at Oil Platform P25 (22.10 o S, 39.91 o W) RMSD U = 0.13 m/s RMSD U = 0.14 m/s 0.4 - 0.0 - -0.4 - 0.4 - 0.0 - -0.4 - 01Jan2014 01Jan2015 HYCOM 1/24 with tides 11Nov2015 31Dec2014 RMSD V (2014) = 0.3 m/s RMSD V (2015) = 0.4 m/s In another oil platforms, the errors of the 24-h forecasts were similar. Zonal Velocity (m/s) Zonal Velocity (m/s)
