Impacts of El Nino and La Nina on interannual snow accumulation in the Andes: Results from a high-resolution 31 year reanalysis

We present new insights on extratropical Andean snow climatology (27 degrees S to 37 degrees S) based on the results from a 31 year high-resolution reanalysis. The snow water equivalent (SWE) estimates were generated by integrating observed snow depletion data from Landsat together with a snow model forced by the Modern-era Retrospective Analysis for Research and Applications. The spatial resolution (180 m), geographic extent (175,000 km(2)), and temporal span (1984-2015) constitute an unprecedented data set for the region. SWE reaches annual peak volumes between 13 and 66 km(3), with a climatological average of 27.7 km(3). A positive correlation between SWE and the Oceanic Nino Index (R-2 = 0.35) exists for the region, with a strengthening of the signal from north to south, peaking at 34 degrees S. Although the correlation between El Nino and positive SWE anomalies is significant, La Nina was not found to drive negative anomalies beyond what is observed during non-La Nina years.