Variabilidade climática inter-anual de Moçambique e sua relação com o fenómeno El-Niño-oscilação Austral, parte II

Abstract

This thesis intends to continue the work started by dr. Lobo in his defense thesis for the degree of degree entitled '' Influence of ENSO on climatic variability '' (Lobo, 1999). Thus, an in-depth analysis is carried out with the objective of identifying the degree of influence of ENSO in the inter-annual variability of Mozambique's climate. The most important modes of spatio-temporal variability are identified to represent the inter-annual variability of precipitation, atmospheric pressure and air temperature for the three most significant months of summer and winter. This is followed by a detailed study of the influence of ENS, characterized by SOI, on the 3 parameters mentioned above. The influence of ENSO for different lags is considered. Correlations are made with the simultaneous and advanced SOI 3,6,9 and 12 months. For summer rainfall, a large part of the Mozambican territory (PC2) has significant correlations and a positive sign (5% significance level) with the SOI advanced 3 months which represents the occurrence of below normal rainfall during the summer as consequence of the start of an ENSO event during the spring of the southern hemisphere. In the rest of the territory, the correlation value is insignificant even for the 10% significance level. During the winter, most of the territory (PCI) has significant and negative correlations (significance level of 5%) with the SOI advanced 6 months. In this case, this association indicates that due to an ENSO event, this region will be able to experience precipitation values above normal 6 months after its beginning. Strong associations are recorded between ENSO and air temperature and atmosphere pressure, indicating that the prevalence of an ENSO event results in higher than normal values for both parameters. Special highlight for the PC2 of the summer temperature and PC1 of the winter temperature, which have very significant correlations for the significance levels of 1% and 5% respectively. Finally, the PCs were subjected to spectral analysis to identify the most important oscillations.(TRADUÇÃO NOSSA)