INSTITUTO ARGENTINO DE NIVOLOGIA, GLACIOLOGIA Y CIENCIAS AMBIENTALES
Unidad Ejecutora - UE
congresos y reuniones científicas
Streamflow variations in subtropical Andes (22-30 S) inferred from instrumental and tree rings records
FERRERO, M.E.; VILLALBA, R.; PRIETO, M.R.
Simposio; LOTRED-SA 3rd International Symposium "Climate change and human impact in Central and South America over the last 2000 years: Observation and Models"; 2014
Universidad EAFIT, PAGES
Runoff in subtropical Andes is the main source of freshwater, and rivers in northwestern Argentina have been (and still are) used for consumption and irrigation of agricultural fields. These activities are seriously affected by climate variability, since analyses of instrumental precipitation and streamflow records for the past 60 years indicate a period of enhanced inter-annual and inter-decadal variations during the last decades. In this contribution we present a multi-proxy perspective of streamflow from the principal rivers in the subtropical region of Argentina. Rivers streamflow reconstructions cover the past 200-400 years and were performed using regression models based on sensitive tree-ring width series. Monthly rainfall and streamflow instrumental data were used to validate tree-ring width reconstructions. The reconstructed streamflow variations were compared with independent historical data to identify inter- or multi-annual patterns on past hydroclimatic variations. Catastrophic events such as droughts and floods were particularly important due to the direct effects on human activities related to natural resources, famine and diseases and Spaniards consistently recorded these events since the 16th century. The development of long-term reconstructions in complement with historical information provide new information on relevant hydroclimatic variables in subtropical Andes and downstream lower regions, as well as the opportunity to improve the understanding of past and present climate variations for the region and related large-scale atmospheric features.