Precipitation Recycling: Unraveling Complexity In Land-Atmosphere Interaction Using MSSA

Francina Dominguez, Civil & Environmental Engineering, UIUC

There is a growing need to understand the sources and sinks of precipitation within a region. In addition to large scale moisture advection, local evaporative sources contribute to rainfall events. This work focuses on understanding the physical mechanisms that affect the contribution of local evapotranspiration to precipitation within a region, or precipitation recycling. Given the many interrelated feedback mechanisms that link the land and the atmosphere, an initial exploratory data analysis using Multivariate Singular Spectrum Analysis (MSSA) has been performed over two different ecological regions of the United States: the central USA plains, and the Sonoran desert. From this analysis we can extract trends and periodicities within the dynamical systems. More importantly, we can link different variables and extract phase relations. In cases where there is limited a-priori knowledge of the dynamics of the physical system, MVSSA provides a useful tool to extract knowledge that can later be used to construct predictive models.