This paper is one in a series of issue briefings the Presidential Climate Action Project is preparing for the presidential candidates and the next president’s transition team on issues where there is potential for bipartisan cooperation.
In brief: The global response to climate change should not stop at eliminating greenhouse gas pollution. Our goal should go beyond net-zero carbon emissions to net-negative carbon emissions. In other words, we should not only prevent CO2 from entering the atmosphere; we should also reduce the CO2 that is already there. The first priority should be to restore and protect natural “carbon sinks” — oceans, soils, forests, wetlands and grasslands. Many of them have been destroyed or degraded by human development. In addition to sequestering CO2, these ecosystems provide a wide variety of important services at no cost, from helping to control floods to recharging groundwater and providing wildlife habitat – co-benefits that engineered carbon sequestration cannot claim. The next president should launch a national program to rehabilitate these sinks. Without taking full advantage of bio-sequestration, If we do not do so it is unlikely that the United States will meet its domestic goals and international commitments to reduce greenhouse gas emissions.
The many commitments in the Paris Climate Agreement including those made by the United States have one central objective: to restore balance in the Earth’s carbon cycle. A variety of natural processes put carbon into the atmosphere, from rotting vegetation to volcanic eruptions. At the same time, a variety of ecosystems remove carbon from the air and store it, including the oceans, soils and forests. When the amount of carbon going into the atmosphere is equal to the amount taken out, the carbon cycle is in balance.
The carbon cycle has been thrown out of balance by human activity. The intensive combustion of fossil fuels during the industrial era has put enormous amounts of carbon dioxide into the atmosphere over the last 200 years, while human development has degraded or destroyed the Earth’s natural “carbon sinks”. The result is climate change.
It is important to understand that carbon is essential to life. It is ubiquitous in the biosphere.i Most of it is stored in rock; the rest circulates through the biosphere, where some of it is captured and stored by natural “carbon sinks” – oceans, soils, grasslands, wetlands and forests. When the amount of carbon kept out of the atmosphere is equal to the amount put in, the carbon cycle is in balance.
During the last 200 years, however, carbon dioxide (CO2) pollution from the combustion of fossil fuels has pushed the carbon cycle out of balance. We are removing carbon from deep within the earth in the form of coal, oil and natural gas. When we burn those fuels to produce energy, their carbon combines with oxygen to produce carbon dioxide (CO2), the most common and one of the longest-lasting greenhouse gases.ii The CO2 that carbon sinks cannot capture and store remains in the troposphere, the lowest layer of the Earth’s atmosphere, where it lingers like a blanket and keeps the sun’s radiation from escaping back into space. The result of this “greenhouse effect” is global warming.
In the United States, the performance of natural carbon sinks has improved in recent years. According to the U.S. Environmental Protection Agency (EPA), the amount of CO2 removed from the atmosphere by natural carbon sinks has increased by 14% since 1990, largely as a result of improved forest management. Biological sinks currently store about 16% of anthropogenic carbon emissions in the United States.iii
The U.S. Forest Service, the EPA and other federal agencies warn, however, that the ability of natural sinks to store carbon will begin declining as soon as 2020. The challenge ahead is to prevent and reverse the decline. Restoring, utilizing, and protecting these ecosystems must be a fundamental component of the nation’s climate-action agenda.
America’s Lost Sinks
Natural carbon sinks are always in flux as seasons change, vegetation ages and dies, and forests succumb to natural fires. Now climate change is becoming a major cause of flux as a result of too much or too little precipitation, excessive temperatures that weaken the ability of trees to combat insect infestations, and so on. On the other hand, warming can increase vegetative cover, which adds to storage.
But human activity including land management practices is a major influence on the ability of ecosystems to sustain the carbon balance. More than half of America’s original wetlands have been destroyed or degraded by agriculture, roads, urbanization or pollution. The loss of coastal marshlands has been evident in the severe damages that storm surges have caused on the nation’s coasts. The loss of wetlands in Louisiana alone, some of them vital to the seafood, recreation and agriculture industries, is staggering, according to the U.S. Geological Survey (USGS).iv
The United States is fourth on the world’s list of forest-rich countries,v and the number of acres of U.S. forestland has remained fairly constant during the past century. But our forests are aging, affecting their ability to store carbon.vi They are vulnerable to disease and fire. While 20% of U.S. forests are protected by conservation programs, nearly 8%, about 58 million acres, were at significant risk from insect and disease mortality in 2006. Many millions of acres of forestlands have been destroyed by wildfires. The U.S. Forest Service says that on average, wildfires are occurring on more than 7 million acres of land every year.vii
An analysis published in Yale’s environment 360viii reports that only 3% of North America’s tallgrass prairie remains intact. As for soils, whose carbon storage potential is second only to oceans, U.S. Department of Agriculture (USDA) data show that in 2009, farming practices resulted in the release of 4.4×109 tons of carbon.ix
What can be predicted, however, is that all of the plans the United States has put forward to reduce its greenhouse gas emissions cannot succeed without carbon storage as well as pollution prevention. “CO2 cannot be reduced to safe levels in time to avoid serious, long-term impacts unless the other side of atmospheric CO2 balance is included,” according to biochemist Thomas Goureau, president of the Global Coral Reef Alliance.
Natural vs. Engineered Carbon Storage
Broadly speaking, there are two types of carbon sinks. The first is biological. The second is mechanical. For example, CO2 is being injected into oil wells to enhance oil recovery. Research has been underway for several years on Carbon Capture and Sequestration (CCS), a technology that would capture CO2 at power plants and factories and store it underground in geologic formations. Some engineers and scientists want more research on geo-engineering, the large-scale manipulation of environmental processes to counteract global warming.
The key differences between natural and engineered systems are simple. First, we know that natural systems work because they have evolved through billions of years of trial and error. On the other hand, many of the most prominent geo-engineering schemes involve unknown costs and high risk of unintended consequencesx.
Another difference: Natural systems offer multiple and valuable economic, environmental and social co-benefits. Wetlands reduce flood damages, help recharge groundwater supplies and provide wildlife habitat. Urban forests help clean the air, reduce storm water runoff, and provide shade that reduces energy consumption, pollution, heat-related illnesses and death from the “urban heat island effect”. Rural forestlands provide habitat, recreation, biodiversity and raw materials in addition to carbon storage. When soils contain healthy amounts of carbon, they retain moisture, become more productive, improve the nation’s food security and increase farm profits while also becoming more resilient to climate change. Conservation tillage techniques allow food producers to grow crops without disturbing soils and releasing their stored carbon.
The rehabilitation and protection of natural carbon sinks also increases America’s restoration economyxi; reduces the need to build and maintain flood control structures; decreases federal budget outlays for disaster recovery; creates new opportunities for the forest products industry; and improves the productivity of agriculture.xii
We have the tools
There is much yet to learn about restoring, managing and sustaining natural carbon sinks especially because of the emerging influences of climate change. More research is critical on how carbon sinks are changing in various regions, how to keep them healthy, and how to measure their performance.
However, the legal authorities, government programs and much of the infrastructure to obtain the multiple benefits of these systems already exist. State and federal governments have a wide variety of programs that can contribute to a national effort on bio-sequestration. Most recently in April 2015, for example, USDA announced a “10 Building Blocks” initiative in which it is partnering with farmers and ranchers to improve the carbon storage capacity of croplands, grazing lands and forests. Other federal programs range from the land management activities at the U.S. Department of Interior, research and data collection by the USGS, and NASA’s ability to monitor ecosystem health from space.xiii
People working on terrestrial sequestration in the private and public sectors are learning lessons from large and small restoration efforts underway around the United States, including those along the Gulf Coast, Mississippi River and Great Lakes. At several locations, communities are restoring wetlands; farmers are practicing conservation tillage and rotational grazing to conserve soils and grasses; private organizations are promoting better stewardship of carbon sinks; and universities are researching how bio-sequestration works.
The potential for common ground is indicated by the fact that some of the most interested groups represent traditionally conservative constituencies. In 2014, for example, 325 hunting, fishing and outdoors groups and individuals representing the $90 billion hunting and fishing industry sent a letter to President Obama in support of his plans to reduce carbon emissions.xiv Groups such as Conservation Hawks and Sportsmen for Climate Action in Tennessee have formed to support climate action because of deteriorating conditions in hunting grounds and fishing venues. On Dec. 18, 2015, two dozen conservation and forest-related organizations wrote to the President that “We and the tens of millions of US forest landowners and managers stand ready to be part of the global effort and the American contribution to mobilize our forests to respond to climate change.”xv
In February 2016, a consortium of groups led by the nonprofit organization Forest Trends and the Nicholas Institute at Duke University published the results of a peer-reviewed analysis of research gaps in the field of terrestrial carbon sequestration.xvi They concluded:
The policy actions with the greatest potential impact and the highest level of certainty include payments for forest carbon sequestration, development of low-emissions agricultural support programs, forest management on federal lands, targeted implementation of agricultural practices, and preservation of existing land uses through urban planning and other non-federal mechanisms.
Substantial ecological restoration efforts are already underway along the Great Lakes, on the Gulf Coast and in the Mississippi River valley. A number of regions and communities are at work to restore the natural wetlands and meander of rivers that reduce inland flooding. Scores of universities, non-government organizations and foundations are already at work studying, demonstrating and applying techniques to increase the bio-sequestration capacity of ecosystems. Bio-sequestration efforts, including USDA’s “10 Building Blocks” initiative, are among the commitments the United States and many other nations have made in the Paris Climate Agreement.
Two organizations, the nonprofit organization Forest Trends and the Nicholas Institute at Duke University, are collaborating to develop a policy roadmap on bio-sequestration – in other words, a guide to public policies that will increase the performance of biological sequestration. The hope is that the next Administration will implement the federal portion of the roadmap and the next Congress will provide existing federal bio-sequestration programs with sufficient resources to do their jobs.
But whether the new Congress and President implement the roadmap and empower the many federal agencies with relevant programs will depend on whether there is strong, bipartisan public support. While landowners must do most the work in a successful national bio-sequestration effort, the federal government can assist by demonstrating best practices on public lands, quantifying the contribution of carbon sinks to U.S. goals, providing technical assistance to land and forest owners, and raising public awareness about ecosystems and their services in general.
PCAP encourages the 45th President and 115th Congress to adopt the following recommendations:
- Issue an Executive Order directing federal agencies to maximize the carbon benefits of their decisions and to use robust frameworks for assessing the land-use carbon impacts of their activities, policies, and programs. For example, incorporate bio-sequestration into agricultural support programs.
- In relevant federal financial assistance programs, offer communities incentives for “high-carbon density zoning” – i.e., ordinances and easements that protect natural carbon sinks.
- Propose to Congress, and use the bully pulpit to champion, increased funding for federal programs that have, or could have, a positive impact on the restoration and conservation of natural carbon sinks.
- Propose and use the bully pulpit to advocate that the next Farm Bill expand programs with impacts of natural carbon sinks, including the coverage of the Sodsaver provisions of the 2014 Farm Bill.
- Urge Congress to expand tax credits and other incentives for forest owners, farmers, ranchers and cities to keep land-based carbon sinks from urban and economic development.
- Encourage and provide technical assistance to states and localities to leverage private financing of land-carbon activities. For example, encourage states that participate in carbon-trading programs or that have public benefit funds to allocate some of their revenues to financial incentives for bio-sequestration.
- Direct the EPA to consider the feasibility of making quantifiable carbon benefits from terrestrial sequestration creditable compliance measures under the Clean Power Plan (CPP).
- Appoint and empower a bio-sequestration leader in the White House to coordinate and maximize the effectiveness of relevant federal resources and programs at USDA, the U.S. Geological Service, the Department of Interior, EPA, NASA and other agencies with applicable authorities, skills and programs.
- Host a White House summit for leaders in the bio-sequestration movement, including farmers, ranchers, public and tribal lands management, ecologists, cities engaged in urban forestry, and others who are qualified to make informed recommendations on changes to federal land management policies.
- Involve the Office of Science and Technology Policy, the Global Change Research Program and DOE’s national laboratories in academic and private sector research on how to maximize the contribution of ecosystems to carbon sequestration.
- Develop an exemplary and internationally replicable bio-sequestration agenda to ratchet up the United States’ land use management commitments in its Individual National Determined Contributions (INDC) plan under the Paris Climate Agreement.
- Enter into bilateral and multilateral agreements, including the French initiative “4 per 1000”, to exchange information, provide technical assistance and set goals for bio-sequestration commitments with other nations, beginning with the most rapidly developing and most carbon intensive economies.
i Life on Earth would not be possible without carbon. In fact, about 18% of the human body’s mass is carbon. It is basic to the formation of proteins, fasts and carbohydrates and to regulating the body’s physiology.
ii In 2013, CO2 was responsible for 82% of U.S. greenhouse gas emissions from human activities, according to EPA.
iii Sources of Green House Gas Emissions: Land Use, Land-Use Change and Forestry Sector Emissions, Environmental Protection Agency (EPA), updated May 26, 2016
vi Carbon Accumulation by U.S. Forests May Slow Over the Next 25 Years, Dave Wear and John W. Coulston, Scientific Reports, November 2015. The authors point out that “Forest growth rates peak and then slow as forests mature so forest aging is a significant driver of sequestration.” The only way to prevent aging is a continuous cycle of harvest, use, and reforestation – in other words the sustainable harvesting and management of forests to optimize their carbon capture. Interestingly, wood building materials and products are one way to sequester carbon.
viii Soil as Carbon Storehouse: New Weapon in Climate Fight?, Judith D. Schwartz, Environment 360, March 2014.
x Geo-engineering proposals range from seeding the oceans with iron to deploying thousands of mirrors in space to reflect sunlight back into space. Critics point out that these devices would try to alter natural systems we clearly do not understand with strategies whose consequences we do not understand.
xii These benefits are not inconsequential. While floods are the most common weather-related disaster in the United States, heat is the No. 1 weather-related killer. Federal spending on disaster recovery could grow out of control as extreme weather events increase. The National Flood Insurance Program is already more than $20 billion in the red.
xiv 325 Sporting Groups Back EPA Carbon Pollution Limits, Miles Grant, National Wildlife Federation, October 2014.
xv Letter to the President from American Bird Conservancy, American Forest Foundation, American Forests, California Forestry Association, CarbonVerde, LLC, Forest Stewards Guild, Forest Trends, Green Diamond Resource Company, Hancock Natural Resource Group, Hardwood Federation, L&C Carbon, LLC, Louisiana Forestry Association, Lyme Timber, Michigan Forest Association, Montana Tree Farm System, National Alliance of Forest Owners, National Association of University Forest Resource Programs, New England Forestry Foundation, Oregon Small Woodlands Association, Society of American Foresters, Sonen Capita, Spatial Informatics Group-Natural Assets Laboratory, Sustainable Forestry Initiative, The Trust for Public Land
xvi Building Carbon in America’s Farms, Forests, and Grasslands: Foundations for a Policy Roadmap, McGlynn et.al., February 2016. Most of the recommendations in this report were drawn from this study.