Though his business card says Director of Forest Carbon Science at The Nature Conservancy, Bronson Griscom introduces himself as an ecological accountant. Griscom radiates an optimism somewhat rare in seasoned environmentalists, especially when he discusses the “carbon economy” of nature: the everyday role that trees, grasslands and coastal habitats play in the carbon cycle. Griscom can measure the carbon impact of logging in old growth forests, or how well different forest ecosystems work as sinks for absorbing and storing carbon from the atmosphere. He helps link our economy with the economy of the biosphere.
Research by The Nature Conservancy and 15 other institutions, published in the Proceedings of the National Academy of Sciences, demonstrates that nature-based solutions provide up to 37 percent of the emission reductions needed by 2030 to keep global temperature increases under 2 degrees celsius-30 percent more than previously estimated.
Additionally, using only cost-effective solutions, nature’s mitigation potential is estimated at 11.3 billion tons in 2030—the equivalent of stopping burning oil globally.
Many natural climate solutions offer additional benefits, such as water filtration, flood buffering, improved soil health, protection of habitat and enhanced climate resilience.
In recent decades, forest use—Griscom’s area of expertise—has been widely studied for its climate impacts. Forest loss accounts for 8 to 10 percent of carbon emissions globally; tropical rainforests like the Amazon have become almost synonymous with land conservation, largely because they work as massive carbon sinks and are home to many of the world’s indigenous people and endangered species.
But other global ecosystems and managed lands—from farmlands and peatlands to seagrass and tidal marshes—have garnered less attention from climate regulators, both as a source of emissions and a potential mitigation solution. In fact, until recently no one had ever integrated the raw data on all the carbon that all ecosystems were already sequestering, and what the potential was for increasing carbon storage among all these habitats together, as Griscom and his team studied.
“I thought we would review a few papers and take an average to answer the question,” he says. “We were shocked to find that important gaps remained in answering the question: how much can lands contribute to solving climate change? So we took it upon ourselves to convene a large group of scientists across 15 research institutions to take a comprehensive look at this question.”
Answering that question became the highest priority for Bronson’s team, and the foundation for what has become the most comprehensive study on the role that nature can play in keeping global temperature increases to 2°C or below. They found that, with the right management, nature can play a bigger role than we realized.