Archival Evidence for some Aspects of Historical Climate Variability in Argentina and Bolivia During the 17^th and 18^th Centuries

Abstract

An overview of past climatic changes inferred from historical sources is presented for southern South America with particular reference to Argentina and Bolivia. The nature of historical sources in these countries is discussed and major climatic events in Argentina and Bolivia during the 17^th and 18^th centuries are presented. Historical records from Mendoza and Buenos Aires, Argentina, indicate that climate during the 17^th was relatively stable with a lower proportion of climatic extreme events. In contrast to the 17^th century, climatic conditions during the 18^th century in the regions of Mendoza, Buenos Aires, northwestern Argentina and Bolivia were variable with marked wet and dry cycles. Between 1780 and 1810, simultaneous with great droughts in the Andean area, abundant rainfalls and extraordinary floods were frequently recorded in the Río de la Plata basin. By comparing the historical ENSO record developed by Quinn with our information about droughts and floods, we found some relationships between the ENSO occurrence and exceptional floods in northeastern Argentina, extraordinary droughts in northwestern Argentina and Bolivia, and heavy precipitation in Mendoza.