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.This doesn't surprise me. The other DrC and I have driven across North America several times in each direction and paid attention to what was happening along our routes. We observed that in the region east of the Mississippi River, any farm field that is allowed to stand fallow for a few years begins to revert to forest. We saw many examples of this.
Before Europeans began cutting trees to create farmland, virtually the entire area east of the Mississippi was one continuous forest. It was then joked that a squirrel could traverse the entire distance from the east coast to Memphis without once setting foot on the ground. Absent human intervention the natural state of this region is forest.
It is also true that most of the land along the Russian water route from St. Petersburg to Moscow is forested and that distance is at least 500 miles. And although I've not seen it myself, vast Siberia is said to be heavily forested as well. Most of Finland is treed too, all of this is boreal forest and it's thriving.
