Regime pluviométrico na Bacia Hidrográfica do Rio Ivinhema-MS no período de 1977 a 2006

Abstract

This research aims to resurface in a study on the rainfall in the river basin Ivinhema-MS, in spatial and temporal scale in the period 1977-2006. The basin is located in south-central state of Mato Grosso do Sul, between the parallel parallels 20 º 51 'and 23 º 14' south latitude and meridians 52 º 21 'and 55 º 57' west longitude. The basin is economically oriented agriculture, possessing significant economic and environmental importance to the territory of Mato Grosso do Sul, lacking climatological studies. Was used as a theoretical reference base some research of authors like Schröder (1956), Monteiro (1973), ZAVATINI (1990), SANT'ANNA NETO (1990) TAVARES (1991), MENARDI JUNIOR (2000), Silva (2001) , BALDO (2006) and BEREZUK (2007), which supported the understanding of rainfall in the studyarea. To understand rainfall was used pluviograms technique developed initially by Schröder (1956) and later adapted and modernized by Silva (2001), which presented new possibilities for analysis of rainfall over the course of its development. It was decided after the primary analysis of the data, the choice of the rain gauge stations with the best and most reliable historical data series, which were the posts located north of the basin being covered for five rain gauges, and the southern portion of six stations, which gathered throughout the basin area and its surroundings. Research reveals two well-defined seasons, one dry and one wet. Also tended to increase the total annual southern sector of the basin and a trend of decreasing rainfall in the northern portion of the basin. Weather events El Niño and La Niña have demonstrated a role in twenty-three years, being responsible for determining how the distribution of rainfall throughout the year, and not directly interfere in the total annual rainfall. Thus the knowledge of the pattern of rainfall distribution allows you to plan activities that occur in the basin, especially activities related to agriculture.