Evaluación de la capacidad de pronóstico del sistema de guía de crecidas repentinas del noreste de Sudamérica (NWSAFFGS) para una subzona hidrográfica priorizada en Colombia

Abstract

Floods and flash floods are recurrent and devastating natural phenomena that cause significant economic losses and threaten the lives and well-being of affected communities, as well as the integrity of river ecosystems. The ability to accurately predict these events is crucial for risk management and urban and rural development planning. This thesis focuses on the verification of the NWSAFFGS system for the prediction of flash floods and floods in a hydrographic subzone, this by verifying three products: the predicted average areal precipitation (FMAP), the average soil moisture (ASM) and flash flood reference values (FFG). Verification is performed using statistical analysis such as Spearman correlation, Root Mean Square Error (RMSE) and bias (BIAS), in addition to the use of contingency tables. In relation to the performance of the system, although it detects the temporary patterns of precipitation, it overestimates the extreme events; compared to the temporal performance it presents a better overall performance in the dry and transition periods. With relation to land management, the issuance of alerts for flash floods is linked with the management of risk during the formulation of Watershed Management and Management Plans (POMCA), incorporating the threat approach linked to the exposed element. Finally, verification of the NWSAFFGS system shows that, although it has potential, its accuracy in predicting extreme events needs to be improved; this will contribute significantly to reducing the risk associated with floods and flash floods, improving planning and decision-making in risk management in vulnerable communities.