Natural climate solutions aren't enough
Protecting carbon sinks, such as forests and wetlands, is key to slowing climate change, but only part of the puzzle, Stanford researchers say. Reducing emissions is still essential for meeting global climate goals.
In the fight to slow climate change, nature is a powerful weapon. In fact, natural climate solutions, such as reducing deforestation and changing farming practices, can soak up excess carbon in the atmosphere and prevent certain emissions so effectively that it might be tempting to think they can buy us time while we figure out how to reduce the amount of greenhouse gases we produce.
Not so, says a group of scientists who published a related perspective piece today in the journal Science. They point out that some groups promoting natural solutions fail to adequately emphasize the urgency of moving away from fossil fuels if we are going to meet global climate goals and avoid the worst effects of a warming planet. This can sow confusion and misunderstanding in the ongoing public conversation.
Stanford Report spoke with Earth scientists Christa Anderson and Chris Field, co-authors of the perspective. Anderson, now a research fellow at the World Wildlife Fund, recently completed her PhD in the Emmett Interdisciplinary Program in Environment and Resources at Stanford’s School of Earth, Energy & Environmental Sciences.
Is there still time to make a meaningful impact to stabilize the climate and slow temperature increases?
CHRIS FIELD: Yes, definitely. The world has clearly passed the point where we can avoid all of the damages from climate change, but every ton of carbon dioxide not emitted decreases future damages. With each passing week, stabilizing warming at well under 2 degrees Celsius, the goal of the 2015 Paris climate agreement, looks increasingly unlikely. But a path of ambitious mitigation can still keep the world in a zone where adaptation can help us cope effectively with the impacts of climate change. If we continue on the present trajectory, we risk warming so great that we lose all options for effective adaptation.
Can natural climate solutions buy us time in terms of reducing our emissions?
CHRISTA ANDERSON: No. The science has long been consistent that even if we maximize our use of natural climate solutions, there is still an emissions gap that requires decarbonizing energy and industry.
FIELD: I agree with Christa that natural climate solutions can’t be viewed as decreasing the urgency of decarbonizing energy and industry. Natural climate solutions make a substantial contribution to solving the climate challenge. They can accelerate the pace of decarbonization and help move the world more quickly to zero greenhouse gas emissions. But they don’t buy time in the sense that they allow a go-slow approach to decarbonizing energy and industry. Every indication is that we need to increase the pace of decarbonizing energy and industry at the same time we take full advantage of natural climate solutions. The latter can decrease the damages from climate change and increase the scope for effective adaptation. One could legitimately ask if this isn’t the same as buying more time. My response is that trading off increased damages against more time is a bad deal. The focus should be on the mix of solutions that minimizes the damages.
Do natural climate solutions have any upsides that other approaches to decarbonization may not?
FIELD: An especially attractive feature is that natural climate solutions can provide important benefits beyond their contribution to reducing climate forcing. These approaches can improve forest habitat, increase agricultural yields and even help improve air and water quality at the same time they provide climate benefits.
If natural climate solutions offer so many benefits, why aren’t we already making maximum use of them?
ANDERSON: While we technically know how to deploy many natural climate solutions, such as planting and growing trees, there are other nontechnical barriers, such as institutional and political challenges, to address. There are also land constraints to consider, including where natural climate solutions can reasonably deployed amid many possible uses for a piece of land.
How can we maximize the effectiveness of natural climate solutions? Any specific examples?
ANDERSON:There are lot of things we can do now. Stopping deforestation is a good example. Technically, we know how to do it, and we have seen some exemplary models, such as Brazil, where deforestation has decreased dramatically through a combination of interventions including policy incentives and stricter governance. Even though deforestation has increased some in recent years, the overall rate is still much reduced in Brazil.
FIELD: The main things we need to do are providing positive incentives for deploying these approaches and eliminating the negative incentives that discourage people from using them. California has a number of greenhouse gas offset programs that incentivize natural climate solutions. These include offset programs for forests, urban forests, livestock management and rice cultivation. For all of these, the magnitude of the positive incentive is linked to the value of carbon credits under California’s cap-and-trade system. Higher carbon price will provide a stronger incentive to deploy natural climate solutions. Negative incentives, such as land concessions for expansion of oil palm cultivation in areas of primary rain forest, will discourage action.
Field is the Melvin and Joan Lane Professor for Interdisciplinary Environmental Studies, a professor of biology and of Earth system science; the Perry L. McCarty Director of the Stanford Woods Institute for the Environment and a senior fellow at the Precourt Institute for Energy.