Climate forcing and extreme events in the Atuel River

MELANIE MEIS; MARIA PAULA LLANO

Trieste

Workshop; Fifth Workshop on Water Resources in Developing Countries: Hydroclimate Modeling and Analysis Tools; 2019

ICTP - International Centre for Theoretical Physics

Forecasting extreme events such as droughts and floods with certain advance is of great importance for decision makers. Both droughts and floods have severe consequences in diverse socio-economical activities that are carried out using water resources. Particularly,water resources management in the west region of Argentina is essential. The economy ofthe region depends heavily on the viniculture and agriculture activity, as well as tourism.Several researchers suggest that there is a relation between droughts and certain climatic oscillations. Rivera et al. (2017) showed the influence of the tropical Pacific ocean region in the development of hydrological droughts. Furthermore, Araneo et al. (2015) have achieved to determine the principal variability intra-seasonal patterns for the Atuel river discharges, in connection to intraseasonal variability from temperatureanomalies over the region basin.In the other hand, the extensive discharge records from different basins have shown that hydrological signals integrate and reflect decadal and multidecadal oscillations (Labat, 2008). In this way, the correlation between streamflow and climatic oscillation could be studied taking into account stochastic models. Multivariate models have been consideredto study the relation among meteorological and hydrological variables in different parts of the world. Aghakouchak et al.(2014) have quantified the joint risk between temperature and precipitation anomalies in certain gauging stations from California, EE.UU, with the aim to collaborate with decision makers. Khendun et al.(2014) modeled the relation between PDO, ENSO and precipitation anomalies in Texas state in order to define aprediction model for extreme events. In this sense, Ward et al. (2014) have exposed that in a global scale the strong and extense influence that ENSO exert over hazard and risk flood.As it has been shown, there is a narrow relation between certain climatic oscillation and extreme hydrological events in several regions of the world. Therefore, any contribution that could be done for quantifying the previous relation is of great interest. In this sense, the principal aim of this work was to study extreme events in Atuel river discharge andits relation with certain climatic oscillations considering a probabilistic model. For this matter, a joint distribution between discharge series and shifted climatic indices was obtained by using copula methods. Moreover, it was possible to validate the obtained resultin time, and a forecast methodology was generated from it. This forecast was also temporally validated, and a simple alarm system is obtained as a result.As it has previously been exposed, the quantification and the understand of hydrological variability is of great deal for risk flood estimation (Kiem et al., 2003), as well as for drought risk. This work can be thought as a simple effective approach for monitoring extreme events using climatic oscillations. It might be useful for decision makers, particularly in water resources management, as the region considered is of high importance for social-economical matters.