Using forests to fight climate change

Forests give us shade, quiet and a difficult challenge in the fight against climate change. Even as forests soak up a good share of the carbon dioxide we humans produce, we are threatening their ability to do so. The climate change we are hastening could one day leave us with forests that emit more carbon than they absorb.

There is a way out of this trap, by striking a subtle balance. Helping forests flourish as valuable “carbon sinks” into the future may require reducing their capacity to sequester carbon now. California is leading theway, as it so often does.

The state’s Forest Carbon Plan would double efforts to thin out trees and clear brush, including by controlled burning. This temporarily lowers carbon-carrying capacity. But the remaining trees draw a greater share of available moisture, so they thrive, restoring the forest’s capacity to pull carbon from the air. Healthy trees are also better able to fend off bark beetles. The landscape is rendered less combustible. Even in the event of fire, fewer trees are consumed.

The need for such planning is urgent. Since 2010, drought and beetles have killed more than 100 million trees in California, and wildfires have scorched hundreds of thousands of acres. California’s plan envisions treating 60,000 acres of forest a year by 2030 — financed by the state’s emissions-permit auctions.

The strategy also aims to ensure that carbon in wood removed from forests is locked away in the form of solid lumber, burned as biofuel in vehicles that would otherwise run on fossil fuels or used in compost or animal feed. New research on transportation biofuels is underway, and the state plans to encourage lumber production close to forest lands. The state also plans to inventory its forests’ carbon-storing capacity every five years.

State governments are accustomed to managing forests but have focused on wildlife, watersheds and recreation. Only recently have they appreciated the vital part forests have to play in storing carbon. California’s plan, which is expected to be finalized by the governor early next year, should serve as a model.