How does deforestation affect rainfall recycling in the southern Amazon and northern Cerrado?

In the southern Amazon and northern Cerrado, deforestation has the potential to significantly affect rainfall by disrupting rainfall recycling, the process by which regional evapotranspiration contributes to regional rainfall. Understanding rainfall recycling in this region is important not only for sustaining Amazon and Cerrado ecosystems, but also for rainfed agriculture, hydropower generation, and drinking water management. Simulations in previous studies suggest complex, scale-dependent interactions between forest cover connectivity and rainfall. For example, the size and distribution of deforested patches has been found to affect rainfall quantity and spatial distribution. Here we take an empirical approach, using the spatial connectivity of rainfall as an indicator of rainfall recycling, to ask: as forest cover connectivity decreased from 1982 - 2014, how did the spatial connectivity of rainfall change in the southern Amazon and northern Cerrado? We use satellite forest cover and rainfall data covering this period of intensive forest cover loss in the region. Forest cover data is from the Hansen Global Forest Change dataset while rainfall is from the Tropical Rainfall Measuring Mission (TRMM) and Climate Hazards Infrared Precipitation with Stations (CHIRPS) datasets. Rainfall spatial connectivity is quantified for seasonal, yearly, and three-year subsets of the 33-year study period using transfer entropy, an information theoretic metric. Analyses reveal a decline in the spatial connectivity of rainfall associated with deforestation.