Sectoral impacts of the hydroclimate variability at different time scales over Northeastern Argentina

GABRIELA V. MÜLLER; MIGUEL A. LOVINO; OMAR V. MÜLLER; LEANDRO SGROI; BAETHGEN, WALTER E.

Congreso; XIII Congreso de Meteorología; 2018

This study discusses the impacts of interannual-to-multidecadal hydroclimate variability on water resources, agriculture and human settlements over northeastern Argentina (NEA). The leading patterns of precipitation, river streamflow and temperature, their nonlinear trends, and cycles are identified by means of a Principal Component Analysis (PCA) and a Singular Spectrum Analysis (SSA). Interannual hydroclimatic variability centres on two broad frequency bands: one of 2.5-6.5 years and the second of about 9 years. Interdecadal variability is characterized by low-frequency trends and multidecadal oscillations that have induced a transition from dryer and cooler climate to wetter and warmer decadesstarting in the mid-twentieth century. The hydroclimate variability at all time scales had significant sectoral impacts. Frequent wet events between 1970 and 2005 favoured floods that affected agricultural and livestock productivity and forced population displacements. On the other hand, agricultural droughts resulted in soil moisture deficits that affected crops at critical growth stages. Hydrologicaldroughts affected surface water resources causing water and food scarcity and stressed the capacity for hydropower generation. Lastly, increases in minimum temperature reduced wheat and barley yields.