Climate and weather conditions of sub-basin of river Cotinguiba-SE

Abstract

The scientific research within the geographical climatology scope shows that, from ancient times, the climate is an important determinant in the shaping of landscape, reflecting on the population distribution, as well as on their productive activities. Among the factors of the physical system, the climate is crucial, because it plays a major role, influencing all the elements of an environmental system. It is the climate which governs the process of input and output of energy within a watershed. In this context, this study aimed to analyze the climatic and meteorological conditions of the Sub-basin of the Cotinguiba river, from the following variables: temperature, precipitation and evapotranspiration in a series of 40 years (1970-2011). Such a study area has a land area of approximately 232.5 km², considered a medium sized and is made by the municipalities of Areia Branca, Laranjeiras, Nossa Senhora do Socorro and Riachuelo in the State of Sergipe. To achieve the proposed objectives, different methodological procedures were used, such as: literature review, secondary data research and mapping collection. In the sub-basin of the Cotinguiba river, the sub-humid climate is predominant, with monthly temperatures ranging between 21.4° and 25.2°C, presenting a small annual temperature range. The rainfall is well distributed throughout the year, and in the wettest months (April, May, June, July and August), the rainfall varies from 205.9 mm to 121.9 mm. During the driest months (December and January), the rate of precipitation usually reaches 40.6mm. Those rainfalls occur due to the interaction of air warm and cold (frontal precipitation) masses that happen most frequently during autumn-winter, often causing floods in the municipalities that comprise the sub-basin, mainly in Laranjeiras city. In the general context of the sub-basin, the referred municipalities present less variable annual rainfall behavior.