Exploración del producto satelital de precipitación IMERG V06 como insumo para la hidrología : determinación de curvas intensidad-duración frecuencia (IDF) sub-diaria y diaria.

Abstract

The scarcity of rainfall data in developing countries makes satellite-based precipitation products play a very important role for hydrological analysis and hydraulic design. In this study, an evaluation of the final IMERG V06 precipitation product with 0.1°x 0.1° spatial resolution over the period of (2000-2001) is presented for the construction of Intensity Duration-Frequency (IDF) curves. The study area is located in the Metropolitan District of Quito (EPMAPS) and stations located in the four cardinal points of Ecuador (INAMHI). Based on annual maximum precipitation series at different durations, fits were made to the most used distributions: Gumbel, Log Normal, Pearson III and Log Pearson III, selecting the best fit by means of goodness-of-fit tests: Chi-square and Kolmogorov-Smirnov. IDF curves were obtained from the distribution function with the best fit. In general, it was found that the IMERG V06 product underestimates intensities for short durations and overestimates intensities for long durations. In the Coast region, the satellite IDF curves were more similar to observations than those observed in the other regions. In the Sierra region, the comparison was detailed since here there is more than one station in a pixel, being the most representative curves those located at higher altitudes, finally in the Amazon region, the results were not very satisfactory.