Climate change endangers the northern forests.

• Author: Acharya, Anjali

From 50 to 90 percent of the boreal forests, the world's largest ecosystem, may disappear because of climate change, according to a recent report by the environmental group Greenpeace. "The Carbon Bomb" warns that a doubling of atmospheric carbon dioxide levels in the next 30 to 50 years could mean the end of the vast forests that surround the Arctic Circle. Other researchers disagree with some of the report's findings but support its recommendations.

Consisting largely of conifers, the boreal forests account for about a third of the world's total forest area. Canada, Alaska, and Scandinavia all contain tracts of boreal forest, but 73 percent of the forests are Russian. These forests play a crucial role in regulating global climate by absorbing large amounts of carbon dioxide that would otherwise contribute to global warming. More carbon may be locked up in the boreal forests than in any other terrestrial ecosystem.

Boreal forests are thought to be especially sensitive to climate change. Drier weather, for instance, could upset the hydrological balance of the widespread bogs, and increase the incidence of fires. Warmer temperatures could open up areas to southern pests or to expanding temperate forests, which could displace native plant communities. According to the report, the past two decades have already seen an increase in pest outbreaks and fires, as well as declines in some...