A global time series of tree-canopy cover maps from 2000 to 2015

Tree-canopy cover—measured as the proportional, vertically projected area of woody plant matter (i.e., leaves, stems, and branches) above a given height—affects terrestrial energy and water exchanges, photosynthesis and transpiration, net primary production, and carbon and nutrient fluxes. Mapped estimates of tree cover provide a measurable attribute upon which to define forests, they are a dominant component of aboveground terrestrial biomass estimates used in regional carbon monitoring and accounting systems, and they serve as an index of plantation agriculture and forestry. The Global Land Cover Facility at the University of Maryland produces time serial maps of tree-canopy cover at 30-meter, annual resolution for 2000, 2005, 2010, and 2015 globally, and for every year from 2011 to 2014 over North and South America. Estimates of tree cover are accompanied by identically scaled maps of measurement and model uncertainty. To improve fit, the global dataset may be calibrated regionally using lidar- and/or high-resolution optical estimates of canopy cover, as well as point-cloud estimates of canopy structure from drone imagery. The data support time-serial detection of change—including harvest, precommercial thinning, fire, insect damage, and regrowth. Data are available for free public download at the Global Land Cover Facility (www.landcover.org) and can be viewed at terraPulse (www.terraPulse.com/terraView/AGU).