Study: Planting trees won’t save planet from climate change

Published: Monday, September 26, 2022 - 5:05am
Updated: Monday, September 26, 2022 - 1:11pm
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As climate change looms and carbon-emissions targets appear less and less achievable, some have suggested locking up carbon by planting trees in drylands.

Large-scale plantings have already begun in China, Saudi Arabia and parts of Africa.

But new research in the journal Science throws some shade on the idea.

Growing forests sequester carbon, but they also change how well the landscape reflects solar radiation.

In drylands, trees store and release more heat than existing groundcover, which offsets their carbon-banking benefits.

The authors found foresting an area roughly half the size of the U.S. would sequester just over 32 billion tons of carbon but add heat requiring almost 23 billion tons to balance.

The remaining carbon savings would offset less than 1% of emissions under medium and business-as-usual scenarios by 2100.

Dryland forestation can provide shade and protect soil, but can also threaten rare species and biodiversity.

The research includes an interactive map depicting the major results.

Science Sustainability