UC Berkeley

Abstract In a recent paper ( M itchard et al . 2014, G lobal E cology and B iogeography , 23 , 935–946) a new map of forest biomass based on a geostatistical model of field data for the A mazon (and surrounding forests) was presented and contrasted with two earlier maps based on remote‐sensing data Saatchi et al . (2011; RS1) and Baccini et al . (2012; RS2). M itchard et al . concluded that both the earlier remote‐sensing based maps were incorrect because they did not conform to Mitchard et al . interpretation of the field‐based results. In making their case, however, they misrepresented the fundamental nature of primary field and remote‐sensing data and committed critical errors in their assumptions about the accuracy of research plots, the interpolation methodology and the statistical analysis. By ignoring the large uncertainty associated with ground estimates of biomass and the significant under‐sampling and spatial bias of research plots, M itchard et al . reported erroneous trends and artificial patterns of biomass over A mazonia. Because of these misrepresentations and methodological flaws, we find their critique of the satellite‐derived maps to be invalid.