author = "Kubota, Paulo Yoshio and Bonatti, Jose Paulo",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)}",
                title = "Variability of precipitation in South America for short term 
            booktitle = "Posters",
                 year = "2010",
         organization = "The Meeting of the Americas.",
            publisher = "AGU",
             keywords = "land, atmosphere interactions.",
             abstract = "This study investigated the behavior of the variability of 
                         precipitation in South America under different surface forcing and 
                         vertical diffusion, based on the assumption that the surface is an 
                         important reservoir of energy. It was used the Atmospheric General 
                         Circulation Model of the Center for Weather Forecasting and 
                         Climate Studies (AGCM-CPTEC/INPE) at the spectral resolution 
                         TQ0213L042 (~ 60 km and 42 vertical layers). It was implemented 
                         the SiB2 and IBIS-2.6 surface schemes and boundary layer 
                         parameterization of Holtslag Boville modified with different 
                         setting options of closure for the calculation of diffusion 
                         coefficient. It was performed for each day during the period of 
                         January 1, 2003 to January 10, 2003, several simulations 
                         (experiments) with forecasting up to 10 days and different 
                         physical combinations of surface and planetary boundary layer 
                         parameterizations. The initial conditions used were the analysis 
                         of the NCEP in the spectral resolution TQ0254L064 degraded to 
                         model resolution and the sea surface temperature in the resolution 
                         of 1 degree, interpolated to model grid. The analyses are based on 
                         the set of simulations produced by physical experiments, where 
                         each member of this group is compared to TRMM3b42 precipitation 
                         data, analysis of the NCEP and the average of the members. The 
                         modification of surface parameterization schemes showed results 
                         with significant dispersion of precipitation as expected, due to 
                         differences in the parameterization formulations. In relation to 
                         the closure options of the boundary layer it was not seen so much 
                         dispersion of precipitation with respect to the control 
                         experiment. To explain the dispersion of precipitation it was 
                         applied the wavelet analyses on the time series of net of energy 
                         on the surface obtained from the energy balance variables of the 
                         experiments. It was removed from the average of the diurnal cycle 
                         to verify the dispersion of the sign of the surface net of energy 
                         (ground, canopy). This method proved to be efficient because, it 
                         has shown qualitatively how the energy stored in surface 
                         dissipates for periods longer than one day. It also shows how the 
                         energy stored during the diurnal cycle may influence the 
                         maintenance of precipitation for a period of time longer. This 
                         behavior can be defined as a signal memory of the surface balance 
                         energy of the diurnal cycle. With the wavelet analyses of the 
                         surface balance energy and the dispersion of precipitation of the 
                         members in relation to control and TRMM3B42 it was concluded that 
                         although more simplified the SSiB scheme represents well the 
                         precipitation and the surface balance energy and presents a clear 
                         signal for periods of 1 to 3 days corresponding to the areas where 
                         precipitation occurs. The SiB2 scheme has the same pattern, but 
                         overestimates the precipitation in the Amazon region. The IBIS 
                         scheme maintains the standard underestimating the precipitation in 
                         the central region of Brazil.",
  conference-location = "Foz do Igua{\c{c}}u",
      conference-year = "8-12 aug.2010",
             language = "en",
           targetfile = "kubota_variability.pdf",
        urlaccessdate = "15 jan. 2021"