Derive probability distributions of tropical deforestation rates for the 1980s and 1990s, by synthesizing the data and uncertainties inherent in AVHRR, TREES, and FRA data. Use the AVHRR data to identify locations of change, and reconciled estimates for the rates. Develop model of land cover change following deforestation for 7 tropical regions, using case-study information. Drive model using deforestation rates from above. Develop spatially-explicit carbon cycle model of land cover change. Evaluate probability distributions of carbon emissions from tropical land cover change in the 1980s and 1990s, incorporating uncertainties in both the land cover change data, as well as in the parameters of the carbon cycle model.A consensus estimate of tropical deforestation rates for the 1980s and 1990s may not be possible --instead derive probability distributions. Historical land cover change influences present-day carbon fluxes. It is important to go back at least 20 years in the Amazon Basin (not tested yet for other regions).