Chaves, Rosane RodriguesPinheiro, José Ueliton2016-10-182016-10-182015-03-18PINHEIRO, José Ueliton. Vórtices ciclônicos em altos níveis sobre o nordeste do Brasil e mudanças climáticas: análise para o clima atual e cenários futuros. 2015. 99f. Tese (Doutorado em Ciências Climáticas) - Centro de Ciências Exatas e da Terra, Universidade Federal do Rio Grande do Norte, Natal, 2015.https://repositorio.ufrn.br/jspui/handle/123456789/21439In this work, was analysed the climate change models's output from IPCC/AR5/CMIP5 that best express the performance of Upper Tropospheric Cyclonic Vortices (UTCV) in Northeast Brazil (NEB), its influence on rainfall and the possibility of projection of future climate scenarios. To achieve the proposed objectives in the thesis were made four EXPERIMENTAL STUDIES.The first, called Pilot, which were evaluated 13 models of climate change and selected the model that best expressed the actions of UTCV in the NEB. The second that evaluated the efficiency of the best model (MIROC4h), comparing it with reanalysis data for a period of 31 years (1975-2005). The third where the future climate scenarios from MIROC4h were analyzed for the period of 21 years (2015-2035). And the fourth where it was analyzed the contribution of UTCV in precipitation over the NEB through the reanalysis data from NCEP/NCAR/DOE. Two approaches comparative statistics were used in the Experimental Studies 1 and 2 with the use of statistical indices: Pearson , Kendall and Spearman's correlations, mean square error of the square root (RMSE), square of the normalized root mean square error (NRMSE), Nash-Sutcliffe (NSE), Kling-Gupta (KGE), Willmott Index (d) Proportion Correct Index (PCI), Critical Success Index (CSI), Probability of Detection (POD), False Alarm Rate (TAF ) and trend rate (BIAS). And in Experiments 3 and 4 were calculated deviations and averages. The results show that the representation of UTCV in climate change models of CMIP5 is feasible, either for the past climate and for the projection of future scenarios. Regarding the contribution of UTCV to precipitate the NEB these present percentages ranging from 47.88% (LNE) to 49.89% (NNE) for the period from October to March. Ceará (49.89%), Piauí (49.49%) and Maranhão (47.88%) are the states where UTCV induce more rainfall and Alagoas (41.93%) and Sergipe (38.03%) are the states where UTCV induce less precipitation. The projection of future scenario for UTCV revealed a 8.97% negative difference in the occurrence of this phenomenon in the NEB and surrounding areas for the period 2015 to 2035. What may impact -4.08% the precipitation of the NEB.Acesso AbertoVórtice ciclônicos de ar superiorModelos do CMIP5Nordeste Brasileiro (NEB)Precipitação no NEBdoctoralThesisCNPQ::CIENCIAS EXATAS E DA TERRA: CIÊNCIAS CLIMÁTICAS