According to new research, the world’s forests play a far greater and more complex role in tackling climate change than previously thought, due to their physical effects on global and local temperatures.
The role of forests as a carbon sink is well established. But comprehensive new data suggests that forests deliver climate benefits well beyond just storing carbon, helping to keep air near and far cool and moist due to the way they physically transform energy and water.
The study found that a band of tropical rainforests spanning Latin America, central Africa and south-east Asia generate the most local and global benefits.
Researchers from Columbia and the US found that overall forests keep the planet at least half of a degree Celsius cooler when biophysical effects – from chemical compounds to turbulence and the reflection of light – are combined with carbon dioxide.
The findings, published in the journal Frontiers in Forests and Global Change, indicate that forests are important to mitigation and adaptation, cooling the air and protecting us from droughts, extreme heat and floods caused by the climate breakdown.
Researchers found that forests emit chemical biogenic volatile organic compounds (BVOCs) which create aerosols that form clouds and reflect incoming energy – both are cooling effects.
Efficient water use, deep roots and so-called canopy roughness also enable forests to mitigate the impact of extreme heat.
These qualities allow trees to move heat and moisture away from the Earth’s surface where we live, which directly cools the local area and influences cloud formation and rainfall – which has ramifications far away.
https://www.theguardian.com/environment/2022/mar/23/forests-climate-crisis-carbon-cooling-effect