Guest essay by Eric Worrall
Who would have thought – apparently a few degrees of global warming won’t make the cold North Eastern states of America, and Eastern Canada, into blazing hot uninhabitable deserts.
Northeastern North America as a potential refugium for boreal forests in a warming climate
A future for boreal forests
Conservation under climate change presents the challenge of predicting where will be suitable for particular organisms and ecological communities in the future. D’Orangeville et al. assess the probable future range for boreal forests in eastern North America, which are expected to be subject to large temperature increases in their natural range. Using tree-ring data from many thousands of forest stands, they delineate the geographical extent of the region where tree growth responds favorably to higher temperatures and where the forest should persist at least until 2070.
High precipitation in boreal northeastern North America could help forests withstand the expected temperature-driven increase in evaporative demand, but definitive evidence is lacking. Using a network of tree-ring collections from 16,450 stands across 583,000 km2 of boreal forests in Québec, Canada, we observe a latitudinal shift in the correlation of black spruce growth with temperature and reduced precipitation, from negative south of 49°N to largely positive to the north of that latitude. Our results suggest that the positive effect of a warmer climate on growth rates and growing season length north of 49°N outweighs the potential negative effect of lower water availability. Unlike the central and western portions of the continent’s boreal forest, northeastern North America may act as a climatic refugium in a warmer climate.
The press release;
The Most Hopeful Place On Earth For Climate Change
Eastern Canada’s black spruce forests are one of the largest untamed wilderness areas on Earth. And in refreshingly optimistic news, parts of this ecosystem are expected to flourish in a warmer world, creating a refuge for species escaping drought-stricken regions to the south and west.
That’s the conclusion of a sweeping new analysis of black spruce trees across 225,000 square miles of forest in Canada’s Quebec province. The research, published today in Science, offers clues as to how this vast ecosystem will fare under human-caused climate change. While the boreal forest’s southern and western regions are likely to struggle with drought in a hotter future, parts of eastern Canada north of the 49th parallel could see a net benefit as the growing season lengthens.
“Climactically speaking, this looks like a system that can take what we think is going to happen in the next 20 or 30 years,” Harvard ecologist and study co-author Neil Pederson told Gizmodo. “It’s hope. It’s a bright spot.”
The boreal forests of North America and Eurasia are some of the most pristine wildlands on the planet. In addition to providing habitat for dozens of charismatic animals, from moose and caribou to foxes and migratory birds, they’re a massive carbon sink, locking away hundreds of billions of tons of organic matter in their soils. That means these forests are not only a sanctuary for biodiversity, but an important regulator of global climate.
“The trees are telling us that it might not be so bad.”