In this collaborative work, the PIs will test the hypothesis that the long-term hydrologic climate of Amazonia is changing as a result of deforestation. A regional coupled atmosphere-biosphere-hydrosphere model will be developed. The model's formulation addresses important limitations in earlier studies of Amazonian deforestation by (i) simulating observed patterns of land-cover change, (ii) simulating the long-term (decadal-to-century scale) consequences of the interaction between the vegetation, atmosphere and land-surface hydrology, (iii) incorporating forest edge effects (sub-grid scale variability in vegetation dynamics associated with forest pasture-interfaces), and (iv) running at spatial resolutions high enough to simulate explicitly mesoscale variability in important hydrologic climate processes such as cloud formation that are caused by fine scale patterns of deforestation. The following three sub-hypotheses will be evaluated: Hypothesis 1: Observed patterns of deforestation are changing the long-term hydrologic climate of Amazonia. Hypothesis 2: The changing hydrologic climate is changing both short (hourly-seasonal-yearly) and long-term (yearly-decadal) vegetation dynamics across the region. Hypothesis 3: Changes in the land surface arising from the changing hydrologic climate are, in turn, shifting the climate and hydrologic cycle towards a more arid state. The constrained model will then be used to predict the future state of the hydrologic climate and vegetation of the region.
The results from this study will be disseminated through webpages and links to existing Amazon research programs. It is planned to prepare an outreach program for high schools in Boston. Graduate and undergraduate students will be involved in the research.
