Zoneamento dos desastres naturais ocorridos no estado do Rio Grande do Sul no período 1989 - 2009: granizo e vendaval

this paper aims to carry out a mapping of wind storms and hails natural disasters occurred in rio grande do sul state during the period from 1989 to 2009. records of the events were obtained at the state civil defense authority to analyze the preferential period for these occurrences and the most affected areas by these events. the results showed that most of the hails occurred in spring (290 events) and in winter (132 events), and the most affected regions were alto uruguai (217 events) and planalto médio (90 events). the regions of depress？o central and miss？es were also affected, but with a slightly lower frequency (83 and 70 events). regarding to wind storms, the most affected areas were those located in the northern half of the state: alto uruguai (271 events), planalto médio (120), depress？o central (116) and miss？es (90), and the highest occurrence were observed in the spring season (preferential period), in the months november and october . in the sea shore, southeast coast and southeast mountains regions few episodes of hails and wind storms have occurred (24, 13 and 11 events respectively), characterizing the south region of the state as the most improbable region for the occurrence of these extreme events. it was also found that hail and wind storms did not occur only in years with presence of the el ni？o and la ni？a climatic events. they also occurred in periods without the influence of these phenomena (normal years).