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Meteorologica 2010
Un esquema de estimación de la precipitación estival en la ciudad de Buenos AiresKeywords: buenos aires city, rainfall, statistical seasonal forecast, sea surface temperature, pattern circulation, multiple linear regression. Abstract: the aim of this study is to estimate december to february rainfall in buenos aires city and its surroundings, using atmospheric variables. summer rainfall in buenos aires was correlated with sea surface temperature, 1000 hpa, 500 hpa and 200 hpa geopotential heights, sea surface pressure, 850 hpa zonal and meridional and specific humidity from the ground to 700 hpa, observed in the previous month. some predictors were selected based on the statistical significance, the independence and the physical meaning and they were used as entrance variables to generate a multiple linear regression using the"forward stepwise" method. the selected predictors were: 1000 hpa geopotential height in the atlantic ocean coast, near 25os and zonal wind in central south america near 15os. therefore the final model showed that summer rainfall is mainly influenced by the weakening of the atlantic anticyclone and the moist air advection from the north. the verification was done for 1984-2007 period and the correlation between the observed and estimated rainfall was 0.61. the stability of the model was proved using a crossvalidation methodology. the results were encouraging and indicate the existence of certain rainfall predictability in summer for buenos aires area.
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