Spatial Intra-Annual Variability of Precipitation Based on Geostatistics. A Case Study for the Paraiba Do Sul Basin, Southeastern Brazil

Abstract

The emphasis in this research is to evaluate the spatial distribution of the precipitation using a geostatistics approach. Seasonal time scales records considering DJF, MAM, JJA e SON periods performed the analysis. Procedures to evaluate the variogram selection and to produce kriging maps were performed in a GIS environment (ArcGIS ®). The results showed that kriging method was very suitable to detect both large changes in the whole area as those local small and subtle changes. Kriging demonstrated be a powerful statistical interpolation method that might be very useful in regions with great complexity in climatology and geomorphology.

Geoprocessing and climate simulation applied to transposition between watershed in São Paulo state, Brazil

“…For the past period, simulated point precipitation rates indicate a variation of up to 74.1% for the annual mean, while in the summer period, this variation reaches 99.8%. These results also agree with those obtained by Silva and Simões (2014) when analyzing the spatial distribution of the observed rainfall for the Paraíba do Sul watershed region.…”

Future scenarios (2011-2040) of temporal and spatial changes in precipitation in the Paraitinga and Paraibuna watersheds, São Paulo, Brazil

“…The average precipitation for the future period (2011-2040) is 1456.3mm, and the irregular distribution of precipitation is persistent for the analyzed period, demonstrating that the formation of the irregular relief, with the presence of mountains and hills (AB'SABER, 2003), generates a spatial irregularity in the distribution of precipitation, results that are similar to those obtained by Silva and Simões (2014). The simulation points with the highest precipitation values were, respectively, the grids P10, P2, P7 and P6, where the minimum average precipitation value was 1027.5mm and the maximum was 1856.5mm, with a variation of 44.6% between precipitation extremes, values that are similar to results from Santos and Fisch (2016).…”

Water security in the Vale do Paraiba´s basin: future scenarios

“…Long-term assessment of water resources is highly unpredictable (Silva and Simões, 2014), and previous studies have shown a bimodal pattern of annual cycle precipitation with dry and wet seasons clearly defined. Folhes and Fisch (2006) quantified the ratio between winter and summer rainfall in relation to the annual precipitation; the values were 8 and 42%, respectively, though the wet rainy period, from spring (Oct) to summer (March), can reach values close to 70%.…”

“…Folhes and Fisch (2006) quantified the ratio between winter and summer rainfall in relation to the annual precipitation; the values were 8 and 42%, respectively, though the wet rainy period, from spring (Oct) to summer (March), can reach values close to 70%. Figure 2, extracted from Silva and Simões (2014), represents the spatial distribution of the rainfall at the Paraíba do Sul watershed. The highest average precipitation is concentrated in the western part (corresponding to the Serra da Mantiqueira Ridge, with altitudes close to 2400 m) and the northeastern portion (corresponding to the Bocaina Plateau, with altitudes of approximately 1400 m).…”

“…Another important rainfall factor is the phenomenon known as the South Atlantic Convergence Zone (SACZ), which can produce high volumes of water during the spring-summer season (Silva and Simões, 2014). Recently, Coelho et al (2017) proposed, based on statistical analysis, that the occurrence of El Nino Southern Oscillation (ENSO) events can influence the onset and the total quantity of rainfall during the wet season: the presence of a positive phase (El Nino) can advance the onset of the rainy period, producing higher overall precipitation.…”