Linear and Nonlinear Aspects Precursors of the Occurrence of Generalized Frosts in the Pampa Humeda Region.

MARILIA DE ABREU GREGORIO; GABRIELA V. MÜLLER; ENVER RAMIREZ

Workshop; 2nd WCRP Summer School on Climate Model Development: Scale aware parameterization for representing sub-grid scale processes; 2018

Frosts are extreme weather events that affect, directly and significantly, human and economic activities, causing impacts and losses in many sectors. The frosts in central-northwest Argentina, a region called Pampa Húmeda, need to be considered because the impacts in this region affects a great number of inhabitants and cause a big impacts in many type of production. This study proposed to identify the Generalized Frost events in the Pampa Húmeda region between 1980 and 2016, after this it will be studied the linear and non-linear interactions (tropics-extratropics, wave-topography and wave-wave) on Rossby waves that are propagated in the Southern Hemisphere and that make synoptic disturbances that cause Generalized Frost in the Pampa Húmeda. The dynamics mechanisms precursors of these events will be analyzed, seeing linear aspects related to the atmospheric circulation and thesynoptic characteristics associated with Generalized Frost. This results will be compared with those obtained previously for another period (1961-1990). On the other hand, the nonlinear interactions (wave-basic state, wave-wave and wave-topography) will be analyzed before and during each Generalized Frost event, in order to determine if these mechanisms can be used as precursors. It will be evaluated if the intervening processes can explain the progress / stagnation and / or persistence of the Generalized Frost events in Pampa Húmeda and also it will be analyzed how these non-linear interactions behave in a basic state during warmed state due to global climate changes.