Methodology for Hansen classification of Global Forest Watch?

The Supplementary Materials (SM) for the Science article provides references to a number of different journal-articles that outline various parts of the methodology.

The SM can be found here

Extending the time-series to include Landsat-5 (and potentially Landsat-8 to make the methodology something that can be rerun "easily") data will be a challenging task, and will require extensive testing of the image normalization. The image normalization may be made even more difficult, due to the lack of coinciding MODIS coverages. Instead, you may have to apply a different normalization approach, such as a combination of COST - article and MAD - article as outlined in this article.

All-in-all, it is not a simple task, and I wish you good luck with it.

The most relevant articles from the SM are:

P. Potapov, S. A. Turubanova, M. C. Hansen, B. Adusei, M. Broich, A. Altstatt, L. Mane, C. O. Justice, Quantifying forest cover loss in Democratic Republic of the Congo, 2000- 2010. Remote Sens. Environ. 122, 106–116 (2012). Article

M. Broich, M. C. Hansen, P. Potapov, B. Adusei, E. Lindquist, S. V. Stehman, Time-series analysis of multi-resolution optical imagery for quantifying forest cover loss in Sumatra and Kalimantan, Indonesia. Int. J. Appl. Earth Obs 13, 277–291 (2011). Article

M. Hansen, A. Egorov, D. P. Roy, P. Potapov, J. Ju, S. Turubanova, I. Kommareddy, T. R. Loveland, Continuous fields of land cover for the conterminous United States using Landsat data: First results from the Web-Enabled Landsat Data (WELD) project. Remote Sens. Letters 2, 279–288 (2011). Article

M. Hansen, R. S. DeFries, J. R. G. Townshend, M. Carroll, C. Dimiceli, R. A. Sohlberg, Global percent tree cover at a spatial resolution of 500 meters: First results of the MODIS vegetation continuous fields algorithm. Earth Interact. 7, 1–15 (2003). Article

L. Breiman, J. Friedman, R. Olsen, C. Stone, Classification and Regression Trees Wadsworth and Brooks/Cole, Monterey, CA, (1984).

Matt Hansen's team has a paper published on forest cover change in Eastern Europe that goes back to 1985 - see Eastern Europe's forest cover dynamics from 1985 to 2012 quantified from the full Landsat archive http://www.sciencedirect.com/science/article/pii/S0034425714004817

I'm also checking with colleagues on whether Matt Hansen's algorithm is available for use within Google Earth Engine.

In the meantime, we'll be updating the Hansen dataset on Global Forest Watch in February, to include data through 2013.