By absorbing carbon dioxide, trees play a vital role in absorbing greenhouse gases resulting from human activities that cause climate warming.
But reforestation also reduces albedo, the ability of a surface to reflect sunlight, to a maximum on snow-covered land and a minimum on bodies of water or forests.
The study, the results of which were published in the journal Nature Communications, showed that reforestation projects that do not include lightness in the equation overestimate the beneficial impact of additional trees planted on the climate by 20 percent to 80 percent.
Co-author of the study, Susan Cook Patton, told Agence France-Presse: “Reforestation in some places leads to clear negative consequences for the climate.”
At a time when many countries have pledged to plant billions of trees, the maps provided by the study are supposed to help officials determine the best places for reforestation and record the best results in reducing climate warming, according to the researcher specializing in forest restoration.
Humid and tropical environments, such as the Amazon Basin and the Congo, allow for high carbon storage with slight decreases in albedo, making them ideal places to restore forest cover.
In contrast, afforestation of grasslands and temperate savannahs is counterproductive, according to Cook-Paton.
“It is not possible to plant trees everywhere,” the researcher said. “We do not have enough money, time, resources, people and seeds, so the goal is to make the most of limited investments and get the best climate return for every hectare of investment.”
