Deforestation and Hydrologic Energy Partitioning in the Amazon Basin
Ryan Knox, Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge
It has been predicted that by 2050, the Amazon River basin's primary closed canopy forest stands will weakly account for half of the land cover. Of this, eight of the Amazon's twelve major hydrologic basins would lose more than half of their forest cover to deforestation. The current and projected rate of disturbance trend is far exceeding that within human history, prompting questions as to the Amazonian vegetation-climate system being pushed beyond the equilibrium thresholds of its ecohydrologic balance. Prior works have shown compelling evidence that Amazonian deforestation enhances the formation of non-precipitating shallow cumulus clouds, while deep cumulus convection is favored over forested land covers. This research supplements these finding by extending the classifications of these tendencies. Swath based measurements of clouds and rainfall are retrieved from the Tropical Rainfall Measurement Mission (TRMM) satellite over the Brazilian state of Rondonia during the day time dry seasons of 1998-2007. The cloud and rainfall detection densities are calculated, referenced to forested and deforested tracks of land and compared. Results generally agree with previous findings, indicating that the frequency of rainfall and dense clouds decrease over deforested regions at least 16km removed from the forest edge.