Impactos da variabilidade e mudanças climáticas em escala regional e global nas regiões hidrográficas do Paraná e Missouri: análise comparativa.

Abstract

The present work deals with comparative investigations of the variability and possible climatic changes occurred in the Hydrographic Regions of Paraná - Brazil (RHP) and Missouri - USA (RHM) between 1970 and 1966. Aiming to diagnose the probable fluctuations and changes in climate that have occurred over the years and to identify if these occur in phase or out of phase between the hydrographic regions. The first step was the mapping of the seasonal climatology of maximum and minimum air temperatures and precipitation using information from meteorological stations. Then the homogeneous regions of precipitation were obtained using Ward's hierarchical method with dissimilarity of the Euclidian distance in the monthly average totals of the precipitation of each hydrographic region. Extreme precipitation and temperature indices were calculated using Rclimdex and trends by the non-parametric Mann-Kendall method. The intrasazonal, interannual and interdecadal variabilities of the precipitation in each homogeneous region of both basins were investigated through the Ondeleta analysis based on the Morlet methodology. Correlations between the indexes of climatic extremes and the ocean-atmosphere indexes were estimated by the Pearson correlation method. The data treated for the generation of thematic maps of land use and cover were obtained in MAPBIOMAS. The graphs to identify the performance phase of the variabilities in the hydrographic regions were generated from the standardized index of extreme temperature indices. The results indicate a consensus regarding the variability occurring in the RHP and RHM indicating that even in different hemispheres and having precipitation and temperature climatology with their maximums in different periods. The analysis of wavelets shows that both hydrographic regions have their precipitation influenced by the multidecadal, decennial and interannual persistent and seasonal scales connected to the Atlantic and Pacific Oceans. This is confirmed by the correlation analyzes between the indices of climatic extremes and the ocean-atmosphere indices. The extremes of temperature and precipitation trends indicate an increase in the frequency and intensity of events in most of the localities of the hydrographic regions. Finally, it was identified that the changes seen in the extreme indexes act in phase, felt simultaneously in the basins indicating that the changes are global, but with great impact on the local scale that are aggravated by changes in the use and coverage of the ground.