Curvas Intensidad-Duración-Frecuencia no estacionarias para la cuenca del río Medellín

Abstract

Las curvas Intensidad-Duración-Frecuencia (IDF) actuales suponen que la precipitación no varía significativamente con el tiempo, subestimando así sus eventos extremos, lo que aumenta el riesgo de inundaciones y de daños en la infraestructura, es por esto que se deben estudiar metodologías que permitan su estimación en condición de cambio climático, es decir, con un enfoque no estacionario, tal como en este estudio, en el que se estimaron curvas IDF estacionarias y no estacionarias para 9 estaciones pluviográficas dispuestas sobre la cuenca del río Medellín. Para ajustar las series de tiempo de precipitación se hizo uso de la distribución de valores extremos EV1, sus parámetros estacionarios fueron calculados por medio del método de los L-momentos y los no estacionarios por el de ventanas móviles. Se evidencia el efecto del cambio climático en intensidades altas y duraciones pequeñas, obteniéndose que el enfoque estacionario puede subestimar los eventos extremos hasta en un 39%.

Análisis hidrológico de caudales máximos en la cuenca alta del río Medellín (Colombia) con condiciones estacionarias y no estacionarias

“…The hydrological characterization was done using two groups of information: rainfall and level data from measurements in stations located within the basin and the IFD curves (stationary and non-stationary) of the area obtained by Grajales (7,8). The design rainfall estimation was done for return periods from 2 to 100 years.…”

“…Due to the increase in the intensity and frequency of precipitation in the Aburrá Valley (Antioquia, Colombia) (7,8), the continuous anthropization of the basin, changes in land use, factors associated with climate change and the intensification of the effects of the ENSO phases (9, 10), the characterization and modeling of peak flows with stationary and non-stationary conditions are required by the government entities in the upper basin of the Medellín River. This study shows the peak flow modeling for different return periods and stationary and non-stationary conditions with different soil moisture conditions.…”

Evaluating the IMERG precipitation satellite product to derive intensity-duration-frequency curves in Colombia

“…The traditional parametric method for constructing IDF curves is based on a statistical analysis of annual maximum series [7,8]. The method consists of calculating annual maximum intensities for different durations (usually 15, 30, 60, 120, and 360 minutes), followed by the fitting of a probability distribution that usually corresponds to one from the GEV (Generalized Extreme Value) family [9,10]. This distribution is used to calculate intensities for selected return periods (usually 2, 5, 10, 25, 50, and 100 years) [11,12,13].…”

“…Several studies described above have shown that sub-daily rainfall information is the basis for calculating IDF curves using a traditional approach [1,10,17]. However, the development of IDF curves continues to be a challenge in the whole world, especially in countries from the Global South that have limitations, if not lack of this type of information [48].…”

“…Additionally, in Colombia and several parts of the world, the number of rainfall stations providing this information has decreased since the 1980s [24]. Considering that IDF curves are the main input for the hydrological design of hydraulic structures and that they represent an important investment for the governments, they need to be rigorously constructed and updated continuously, as they are derived from extreme rainfall that are non-stationary [10]. Constructing and updating IDF curves from analog information, like in Colombia, is a time-consuming and costly process [17].…”