Why the Trees Are Marching Northward

Andru Okun in Undark: Although the speed and severity of climate change are both uncertain, it’s clear by now that warming is inevitable. Rising temperatures will impact every organism on the planet and recast the landscape. In truth, highlights British writer Ben Rawlence, this process is well underway. In “The Treeline: The Last Forest and the Future of Life on Earth,” he devotes his attention to the boreal forest, also known as the taiga, the broad tract of deciduous and coniferous forests covering the far northern expanses of the Earth. Spanning roughly 1.5 billion acres, the boreal contains a staggering one-third of the Earth’s trees. However, as Rawlence writes, “The trees are on the move.”

As the melting of permafrost and Arctic sea ice hastens atmospheric warming, the boreal is pushing farther north. The implications of this shift are troubling. While southern regions of the boreal have been marred by deforestation, tundra — the typically cold and treeless landscape ringing the North Pole — has begun transforming into woodland. As the trees propagate in formerly barren northern regions, microbial activity is warming the soil further, thawing frozen earth containing large quantities of greenhouse gas. More here >