Good post, but I'm confused.

Take a specific case: FAO's "Global Forest Resources Assessment 2010" Table 3 suggests Indonesia lost 0.31% forest from 2000 to 2005. But Hansen et al ('Quantification of global gross forest cover loss' PNAS) put it at 3.36%.

How accurate are FAO estimates? If they are anything like their crop estimates the answer must be 'not very'?

P Baker: The shortcomings of FAO data are well-known and well-documented [e.g. Alan Grainger (2007). Difficulties in tracking the long-term global trend in tropical forest area. Proceedings of the National Academy of Sciences January 7-11, 2008.] But at present, these are the best available on a global scale. Furthermore, the trends are largely confirmed by Hansen et al. where they have conducted their analysis. But better data will be available soon. FAO is even improving its methodology to incorporate remote sensing rather than self-reporting.