North American Vegetation 1990–2100

Climate affects ecosystems and the response of terrestrial vegetation to accelerated climate change (global warming) has been predicted using climate models, calculated with the help of computer programs. It has been projected that, by c. 2100, much of North America’s forests will have vanished and dry grassland will spread northwards, with the extreme northeast becoming boreal desert. The sea level will have risen and some parts of the US – Florida, New Orleans, Virginia and parts of Washington D.C. – may have been engulfed. While this projection may not prove to be wholly realized, the climate change scenario is potentially devastating. Forests absorb 25 to 30 per cent of carbon dioxide emissions and in North America the forests are shrinking and trees growing more slowly. It is thought that 2050 will be the ‘tipping point’, with North American forests no longer being climate assets, but carbon producers.