Título:
Precipitation trends in Mainland Portugal in the period 1941-2000
Resumo:
The presence of a trend in hydrologic parameters can result from the highly variable nature of hydrological processes or be related to climate variations. The purpose of this work is to contribute to a better understanding of the variability of precipitation by investigating recent trends in the temporal structure of this process in Mainland Portugal. The study uses annual and monthly precipitation data from 107 locations scattered over the territory. The time span of the records is 60 years, from 1941 to 2000. The data are analyzed using statistical methods (e.g. Mann-Kendall trend test). In order to take into account seasonality and serial correlation, the different months of the year were analysed separately. The analyses of both annual and monthly data lead to a characterization of changes in the distribution of precipitation over Mainland Portugal and within the year.
Autores:
M. Isabel P. de Lima, João L.M.P. de Lima, Ana C.P. Marques, M. Fátima E.S. Coelho