Size fluctuations in endorheic lakes in northwestern Argentina (NWA) andsouthwestern Bolivia (SWB) are very sensitive to basin hydrological balances,and consequently, very vulnerable to deleterious effects from climaticchanges. The management of these water resources and their biodiversityrequires a comprehensive knowledge of their natural variability over multipletimescales. In this study, we present a multi-century reconstruction of pastlake-area fluctuations in NWA and SWB. The evidence used to develop andvalidate this reconstruction includes satellite images and a century-longtree-ring record from P. tarapacana. Inter-annual fluctuations inlake area of nine lakes were quantified based on Landsat satellite imagesover the period 1975 to 2009. A regional P. tarapacana tree-ringchronology, composite from two sampling sites, was used as predictors in aregression model to reconstruct the mean annual (January–December) lake areafrom the nine lakes. The reconstruction model captures 62 % of the totalvariance in lake-area fluctuations and shows adequate levels ofcross-validation. This high-resolution reconstruction covers the past601 yearsand characterizes the occurrence of annual to multi-decadal lake areafluctuations and its main oscillation modes of variability. Ourreconstruction points out that the late 20th century decrease in lake areawas exceptional over the period 1407–2007; a persistent negative trend inlake area is clear in the reconstruction and consistent with glacier retreatand other climate proxies from the Altiplano and the tropical Andes. Sincethe mid 1970s, the Vilama-Coruto lake system recorded an accelerated decreasein area consistent with an increasing recurrence of extremely small lake-areaevents. Throughout the 601 years, the reconstruction provides valuableinformation about spatial and temporal stabilities of the relationshipsbetween changes in lake area, ENSO, and PDO, highlighting the Pacificinfluence over most modes of lake area variability. Global and regionalclimate models for the Altiplano project a marked reduction in precipitationto the end of the 21st century, exacerbating presently dry conditions. Theseresults provide a baseline for the historical range of variability in lakefluctuations and thus should be considered for the management of biodiversityand water resources in the Central Andes during the next decades.
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