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Land change is a cause and consequence of global environmental change1,2. Changes in land use and land cover considerably alter the Earth's energy balance and biogeochemical cycles, which contributes to climate change and-in turn-affects land surface properties and the provision of ecosystem services1-4. However, quantification of global land change is lacking. Here we analyse 35 years' worth of satellite data and provide a comprehensive record of global land-change dynamics during the period 1982-2016. We show that-contrary to the prevailing view that forest area has declined globally5-tree cover has increased by 2.24 million km2 (+7.1% relative to the 1982 level). This overall net gain is the result of a net loss in the tropics being outweighed by a net gain in the extratropics. Global bare ground cover has decreased by 1.16 million km2 (-3.1%), most notably in agricultural regions in Asia. Of all land changes, 60% are associated with direct human activities and 40% with indirect drivers such as climate change. Land-use change exhibits regional dominance, including tropical deforestation and agricultural expansion, temperate reforestation or afforestation, cropland intensification and urbanization. Consistently across all climate domains, montane systems have gained tree cover and many arid and semi-arid ecosystems have lost vegetation cover. The mapped land changes and the driver attributions reflect a humandominated Earth system. The dataset we developed may be used to improve the modelling of land-use changes, biogeochemical cycles and vegetation-climate interactions to advance our understanding of global environmental change1-4,6.
Humanity depends on land for food, energy, living space and development. Land-use change-traditionally a local-scale human practice-is increasingly affecting Earth system processes, including the surface energy balance, the carbon cycle, the water cycle and species diversity1-4. Land-use change is estimated to have contributed a quarter of cumulative carbon emissions to the atmosphere since industrialization3. As population and per capita consumption continue to grow, so does demand for food, natural resources and consequent stress to ecosystems.
Because of their synoptic view and recurrent monitoring of the Earth's surface, satellite observations contribute substantially to our current understanding of the global extent and change of land cover and land use. Previous global-scale studies have mainly focused on annual forest cover change (stand-replacement disturbance) for the time period after 20 007, or focused on sparse temporal intervals8. Longterm...