HR: 1340h
AN: GC13A-0953    [Abstracts]
TI: Streamflow Interdecadal Variability Analysis for Rivers in Southern Chile and its Connections With Climate and Land-use Change
AU: Rubio-Alvarez, E
EM: eduardo.rubio.a@gmail.com
AF: Departamento de Ingenieria Civil, Facultad de Cienias Fisicas y Matematicas. Universidad de Chile, Av. Blanco Encalada 2002, Santiago, RM 8370449, Chile
AU: * McPhee, J
EM: jmcphee@ing.uchile.cl
AF: Departamento de Ingenieria Civil, Facultad de Cienias Fisicas y Matematicas. Universidad de Chile, Av. Blanco Encalada 2002, Santiago, RM 8370449, Chile
AB: The time-series of annual and seasonal streamflow for 30 rivers in Southern Chile spanning five degrees latitude between VII Region of Maule and IX region of the Araucania ( -34°41' to -39°37') for different periods between 40 - 60 years are analyzed. The analysis includes application of the Multitaper Method (MTM) and the Maximum Entropy Method (MEM) to find the periodicities or interannual and decadal cycles. Previously SSA is applied in order to augment the signal-to-noise ratio. It is hypothesized that trends in streamflow are associated with the effect of climate change in Southern Chile, which predicts a decline in precipitation for higher latitudes; and cycles are related of the cycles of ENSO-3, SST, PDO and SOI. We also analyze the spatial variability using multivariate analysis. Analysis of the Maule region clearly shows two cycles significant at 95% confidence, 2 and 6 years. We have found that coastal watersheds present stronger streamflow variability between consecutives years than mountainous basins.
DE: 1834 Human impacts
DE: 1860 Streamflow
DE: 1872 Time series analysis (3270, 4277, 4475)
DE: 1879 Watershed
SC: Global Environmental Change [GC]
MN: 2007 Fall Meeting