Reforestation keeps Eastern U.S. cool
A century of reforestation in the Eastern U.S. is keeping regional climate change at bay, according to a new study published in Earth’s Future. Scientists pored over data from satellites, maps, and 400 weather stations spanning 110 years to show that regional temperatures rose more slowly than the rest of the United States as 15 million hectares (37 million acres) of forest regrew.
“Our work indicates reforestation contributed to the historically slow pace of warming in the [Eastern US], underscoring reforestation’s potential as a local climate adaptation strategy in temperate regions,” the study concludes.
Eastern U.S. forests cool the land surface by 1–2°C (1.8 to 3.6 °F) annually compared to nearby grasslands. During the hottest times of the summer, forest can provide cooling benefits that reach 5°C (9°F). Young forests aged 25–50 years provide the strongest cooling, according to the study.
It’s not just shade, it’s the moisture evaporating from trees, called transpiration, that provides cooling benefits to areas up to 400 meters away from a forest.
“Moving forward, we need to think about tree planting not just as a way to absorb carbon dioxide but also the cooling effects in adapting for climate change, to help cities be resilient against these very hot temperatures,” study co-author Mallory Barnes told the Guardian.
Forests from New York to Florida were cut down for agriculture and building materials over several hundred years of European colonization. These forests began to regrow a century ago as people moved to cities.
Urban planners have long known that planting trees can help keep a city cool as they grapple with the rise of scorching cities, where concrete, asphalt, and metal absorb heat during the day and continue to emit it at night.
The New York Times has reported on Singapore’s efforts to design “cooler” architecture by integrating vertical forests and rooftops gardens. Yale360 recently interviewed Eleni Myrivili, the United Nation’s global “Chief Heat Officer,” on Athens’ efforts to build pocket parks and green corridors to deal with heat waves.
As extreme heat becomes the top public health issue cities face, bringing in more trees has been dubbed “climate change adaptation.”
“We have to ramp up resilience and adaptation financing because we’ll save lives and ecosystems,” Myrivili told Yale360.
The post Reforestation keeps Eastern U.S. cool appeared first on EARTH HOPE.
Wow! Great article. I worked in land conservation most of my career and didn’t know this. Thanks.