Downscaling Large-Scale Atmospheric Information To Local Scales Using A Two Step Statistical Method.

BETTOLLI, ML; PENALBA, OC; RIBALAYGUA, J Y TORRES MICHELENA

Foz de Iguazu

Congreso; The Meeting of the Americas. AGU 2010; 2010

AGU

Regional and global atmospheric models properly describe climaticfeatures at subcontinental scales but their use for local impact studies islimited. This is due to their low spatial resolution and incapacity to representimportant characteristics at subscale resolution. An alternative to solve thisproblem is to apply empirical relationships between local climate and regionalatmospheric systems. This procedure is known as downscaling. This workproposes a statistical downscaling methodology in order to derive local climaticestimates from large-scale atmospheric predictors in La Plata Basin (LPB)region. This is a particularly suitable region for the application of downscalingmethods, since climate variability and global changes have a strong impact onagricultural and hydropower production. The low resolution predictors usedhere were 1000, 850 and 500 hPa geopotential heights ERA40 Reanalyses ata 6-hourly resolution were used to derive daily mean geostrophic wind fields foreach level and hourly 1000/500 hPa and 1000/850 hPa thickness