Hydroclimate variability in the Subtropics of Argentina and potential for water resources management

VILLALBA, R.; FERRERO, M.E.; MEKO, D.

Huaraz

Congreso; International Congress on Climate Change and its Impacts; 2017

Sociedad Geológica del Perú

Mountain regions in subtropicalArgentina are the main source of freshwater and hence populations areclosely linked to the presence of rivers in the region. Nevertheless,the variability of rivers´ streamflow can cause repeated floodings ofvarying magnitude that affect the peri-urban areas of Salta, thesecond largest city in northern Argentina. Repeated overflows of theArias-Arenales river, often impact the most humble neighbourhoodswith little capacity to respond to environmental contingencies.In northwestern Argentina, rivers´streamflow are mainly modulated by precipitation, but instrumentalrecords barely exceed 40 years of data. In that case, tree rings canbe used to reconstruct and extend this hydroclimatic records. We usedtree-ring chronologies from the active basin of mountain regions toreconstruct the Arias-Arenales hydrological variability. Thereconstruction of the annual precipitation from the Arias-Arenalesbasin show that the frequency and magnitude in the events of largeprecipitation have increased during the last decades; therefore, theriver flow responses will be similar.The information extracted from thetrees represents a very adequate environmental record since it allowsto extend the instrumental series and characterize the climaticvariability in the region both temporally and spatially. This canprovide water managers and decision makers with larger windows ofhydrological than instrumental records, thereby capturing greatermodes of variability, essential for proper water planning.