ABOUT THOSE “VANISHING” FORESTS. . .
Most people think—and charlatan environmentalists are happy to reinforce the impression—that deforestation is taking place on a massive scale, that the world is literally going to run out of trees. I have noted from time to time the data from the United Nations Global Forest Resource Assessment (UNGFRA) that has found that deforestation stopped at least 25 years ago, and that net reforestation has been taking place.
But the UN data is not as good as one would like. This week, however, Naturemagazine published a major new studywith much more precise measurements and analysis than the UNGFRA based on 35 years’ worth of satellite imagery, and it finds that since 1982 global forest cover has increasedby 7.2 percent, or 2.24 million kilometers.
Here’s the abstract:
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 services. 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 globally—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 human-dominated 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 change. (Emphasis added.)
Don’t expect to hear environmentalists or the media note and celebrate this news. If it makes the news at all.
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