Multi-century tree-ring based reconstruction of the Neuquén River streamflow, northern Patagonia, Argentina

摘要: In most cases, gauged river flow records in southern South America extend for only a few decades, hampering the detection of long-term, decadal to centennial-scale cycles and trends. Long streamflow series can be reconstructed from tree-ring records, offering opportunity extending limited hydrological instrumental data several centuries. northern Patagonia, Argentina, Neuquen River has great importance local national socio-economic activities such as hydroelectric power generation, agriculture tourism. this study, new updated chronologies Araucaria araucana Austrocedrus chilensis are used reconstruct October–June mean place period flows (1903–2009), multi-century context. The reconstruction covers 1346–2000 AD was developed network 43 chronologies, grouped composite series, using nested principal component regression approach. Analyses frequency, intensity, duration droughts pluvial events indicate that 20th century contains some driest wettest annual decadal-scale last 654 yr, but longer more severe were recorded previous Blackman-Tukey singular spectral analyses identified quasiperiodic oscillations 3.5 17.5 yr. A dominant 6.8-yr cycle explains ca. 23.6% total variance reconstruction. Correlation showed discharges related variations Southern Annular Mode (SAM), measure air mass exchanges between middle high latitudes Hemisphere. This association is consistent with studies strong correlation rainfall Patagonia SAM variations.