Restoring tree cover sounds as if it would help cool the Earth. But sometimes it can actually heat it up by affecting how much sunlight the surface reflects — an effect called “the albedo.” Two Clark researchers have provided a tool that practitioners and land managers can use to determine just how much of a problem albedo is for any reforestation or afforestation project on the globe.
Sorting out “the good climate solutions from the bad”
Working with their peers from The Nature Conservancy (TNC) and ETH-Zurich, Natalia Hasler, a research scientist at the George Perkins Marsh Institute, and Christopher Williams, associate professor in the Graduate School of Geography, use new maps to show that previously published “carbon-only” estimates of the global climate mitigation potential of restoring trees worldwide provided significant overestimation, being anywhere from 20 to 81 percent too high.
“The balance of carbon storage versus albedo change that comes from restoring tree cover varies from place to place, but until now we didn’t have the tools to tell the good climate solutions from the bad,” Hasler says. “Our study aims to change that, providing the maps needed to empower smarter decisions while also ensuring that limited finance is directed at those locations where restoring tree cover can make the most positive difference as a natural climate solution.”
Their study was published in the journal Nature Communications.