O seminário extra do Departamento de Ciências Atmosféricas do IAG/USP terá como tema: "Seasonal rainfall forecasts for South America with a simple GCM", com apresentação de Nick Hall.
Abstract: Understanding intraseasonal variability of rainfall over South America has been a research goal for decades, driven by the need to make predictions for agriculture and energy sectors. Much of the academic work has been conducted with idealised models, whereas the tool of choice for seasonal predictions is usually a fully specified GCM.
In this work we try to combine the two approaches, using a relatively simple dynamical model of the global atmosphere to make predictions. The model is called DREAM (Dynamical Research Empirical Atmospheric Model). It consists of a dynamical core and some simple representations of dissipation. Most of the costly physical parameterisations are replaced by an empirical representation of source an sink terms derived from reanalysis data. The key elements that need to be added to make rainfall predictions are 1) a precipitation scheme and 2) a method for including the effect of SST anomalies.
I will explain how this model works, and some of the successes and failures in trying to adapt it to make seasonal forecasts. The latest forecast will be shown together with evaluations of hindcast skill. DREAM has the potential to be a light-weight portable prediction system for tropical countries, and can also be configured for academic studies and for teaching.
Haverá transmissão pelo canal do Departamento de Ciências Atmosféricas: https://www.youtube.com/@AtmosferaIAGUSP/live