Global tree cover data (treecover2010) are per pixel estimates of circa 2010 percent maximum (peak of growing season)
tree canopy cover derived from cloud-free annual growing season composite Landsat 7 ETM+ data.
A regression tree model estimating per pixel percent tree canopy cover was applied to annual
composites from 2000 to 2012 inclusive (Hansen and others, 2013). Data gaps and noise from individual
years were replaced using multi-year median values. First, a median from annual tree canopy cover
values from 2009-2011 was used to estimate 2010 tree cover. For pixels still lacking an estimate,
the median calculation was expanded to include tree cover values from 2008-2011, then from 2008-2012.
Any remaining gaps were filled with tree canopy cover values derived from a regression tree model
using all growing season Landsat ETM+ data as inputs. The resulting layer represents estimated
maximum tree canopy cover per pixel, 1-100% for the year 2010 in integer values (1-100).
Tree cover canopy percentage per output grid cell is encoded as integer values (1-100).
Files are unsigned 8-bit data with spatial resolution of 1 arc-second per pixel
(approximately 30 meters per pixel at the equator). Data coverage is from 80° north to 60° south.
It is divided into tiles of 10 x 10 degrees. Tiles over ocean area are included for completeness.
- Potapov, P., Turubanova, S., Tyukavina, A., Krylov, A., McCarty, J., Radeloff, V., and Hansen, M., 2015,
Eastern Europe's forest cover dynamics from 1985 to 2012 quantified from the full Landsat archive: Remote Sensing
of Environment, v. 159, p. 28-43, at
Hansen, M.C., Egorov, A., Potapov, P.V., Stehman, S.V., Tyukavina, A., Turubanova, S.A., Roy, D.P., Goetz, S.J., Loveland,
T.R., Ju, J., Kommareddy, A., Kovalskyy, V., Forsyth, C., and Bents, T., 2014, Monitoring conterminous
United States (CONUS) land cover change with Web-Enabled Landsat Data (WELD): Remote Sensing of Environment,
v. 140, p. 466-484, at ://000329766200038.
Hansen, M.C., DeFries, R.S., Townshend, J.R.G., Sohlberg, R., Dimiceli, C., and Carroll, M., 2002,
Towards an operational MODIS continuous field of percent tree cover algorithm: examples using AVHRR
and MODIS data: Remote Sensing of Environment, v. 83, no. 1—2, p. 303-319, at
Hansen, M.C., Potapov, P.V., Moore, R., Hancher, M., Turubanova, S.A., Tyukavina, A.,
Thau, D., Stehman, S.V., Goetz, S.J., Loveland, T.R., Kommareddy, A., Egorov, A., Chini, L.,
Justice, C.O., and Townshend, J.R.G., 2013, High-Resolution Global Maps of 21st-Century
Forest Cover Change: Science, v. 342, no. 6160, p. 850-853,
University of Maryland, Department of Geographical Sciences and USGS; use is free to all if acknowledgement is made.
[ https://landcover.usgs.gov/glc/TreeCoverDescriptionAndDownloads.php ]