This resource is part of the publication by Hansen et al. (2013) "High-Resolution Global Maps of 21st-Century Forest Cover Change". It represents "Forest loss during the period 2000–2021, defined as a stand-replacement disturbance, or a change from a forest to non-forest state. Encoded as either 0 (no loss) or else a value in the range 1–20, representing loss detected primarily in the year 2001–2021, respectively." Due to changes in the satellites products used in the compilation of the tree loss product, results before the year 2011 and afterwards are not directly comparable until reprocessing has finished. Users should be aware of this limitation, especially when the timeframe of the analysis spans over the two periods delimited by the year 2011.
References
Hansen, M. C., P. V. Potapov, R. Moore, M. Hancher, S. A. Turubanova, A. Tyukavina, D. Thau, S. V. Stehman, S. J. Goetz, T. R. Loveland, A. Kommareddy, A. Egorov, L. Chini, C. O. Justice, and J. R. G. Townshend. 2013. “High-Resolution Global Maps of 21st-Century Forest Cover Change.” Science 342 (15 November): 850–53.