Analysis of the factors and dynamic agents that produced the most extreme snowy droughts in the San Juan River basin and its surroundings

Abstract

Between 1909 and 2021, the region of the San Juan River basin and its surround- ings endured two significant periods of extreme drought, registering 2021 as the scarcest snowy season since 1909. These deficit intervals have not only impacted on the availability of water for human consumption, but also affected the productive sector and water infrastructure. This prompted the authors to investigate the nature of these droughts, which is fundamental for hydroclimatic studies, particularly in this region.

This work studies the dominant climatic factors and agents that contributed to the occurrence of extreme snow drought, aiming to identify and assign them a level of importance, thus providing the physical basis for the development of downscaling from dynamic and statistical forecasting models, which can be used as potential predictors of future snow seasons.

In conclusion, it is found that the complexity of the interplay of factors leading to the most severe snow droughts in the Arid Andes in most cases are neither coinci- dent nor periodic due to the fact that these predictors are not always associated in the same way; therefore, the prognosis is very complex.