Caracterização do regime pluvial do semiárido paraibano utilizando série de Fourier

Abstract

In the semi-arid region of Paraíba, prolonged droughts and desertification have led to changes in the hydrological regime, losses in agriculture, threats to biodiversity, and social, economic and environmental impacts. Although the Fourier series has been developed as a mathematical subsidy to the study of heat transfer, the application of this sum of sines and cosines has extended to all branches of Physics, Engineering and Mathematics, being also common to find the use of this series in several Published articles on human knowledge. The objective of this study was to evaluate the periodicity of rainfall occurring in the regions of Agreste and Cariri Paraibano by means of Fourier series, since it is a technique used to describe periodic or quasi-periodic phenomena in the frequency domain of a series of data ordered in Time, presenting as results for the Agreste a period of drought between the months of October to December and the rainy season between the months of April to July. In turn, for Cariri there is a period of drought between the months of September to December and the rainy season between January and April. For the monthly analysis the first three harmonics are the ones that best describe the model and for the annual analysis they are the first five harmonics. In the monthly analysis it was concluded that for the Agreste and Cariri the interval between two peaks of minimum and maximum consecutive occurs every twelve years and for the Agreste, the interval between a peak of minimum and one of peak occurs every six years; For Cariri, this interval occurs every five years.