Posted on 25 March 2021 by Guest Author

This is a re-post from Yale Climate Connections by Bruce Lieberman

Among the many goals in President Biden’s climate change agenda, protecting 30 percent of U.S. lands and ocean territories by 2030 is among the most ambitious. And among the most complex.

The administration initiative is likely to face political headwinds in a divided government.

Nevertheless, achieving the “30 by 30” goal could be a critical marker on the road toward a carbon-free future. The reason: Natural landscapes and seascapes are powerful carbon sinks, pulling CO2 from the atmosphere and storing carbon in soil, grasses, shrubs, and trees, coral reefs, sea grasses, and ocean floor sediments.

“It’s impossible to overstate the importance of protecting more of America’s – and the world’s – natural places,” a group of senior staff members at the Natural Resources Defense Council wrote shortly after President Biden’s announcement.

“This life support system … plays a vital role in pulling planet-warming carbon out of the atmosphere and sequestering it away,” the NRDC group wrote. “Protecting 30 percent of America’s natural areas will help stabilize the climate, protect biodiversity, and give plants and wildlife a chance to adapt to the warming already baked into our current climate.”

Plan requires ingenuity, consensus, broad commitment

It’ll take a lot of ingenuity, a lot of consensus, and a lot of sustained commitment across the nation to make the 30 by 30 vision a reality. Today, only about 12 percent of America’s land area is under some type of environmental protection, while about 26 percent of the country’s ocean territories are protected. The nation is well on its way to achieving the 30 by 30 goal offshore, but getting to 30 percent on land has a long way to go. In total, it’ll require environmental protections for a combined land area equal to twice the size of Texas.

The challenges notwithstanding, President Biden’s 30 by 30 goal hasn’t come out of thin air. Scientists, conservationists, environmental organizations, and others have long advocated for protecting natural habitats – primarily to protect biodiversity. Biologist E.O. Wilson, for instance, in his 2017 book, “Half Earth: Our Planet’s Fight for Life,” called for 50 percent of the planet to be preserved in its natural state.

But the role of natural landscapes as powerful carbon sinks also has been widely recognized. Global opposition to clearing rainforests in South America, southeast Asia, and other tropical regions, for instance, not only brings attention to massive losses of biodiversity; it also raises alarm that losing these forests means losing places that store vast amounts of atmospheric carbon.

In their 2019 study, “A Global Deal for Nature,” a group of conservation biologists wrote that protecting natural lands “not only safeguards biodiversity but also is the cheapest and fastest alternative for addressing climate change and is not beholden to developing carbon removal technologies unlikely to be effective or to scale in the time-bound nature of the current twin crises.”

In the U.S., what might 30 by 30 look like? And how will we get there?

President Biden has tasked the Secretary of the Interior, “in consultation with the Secretary of Agriculture, the Secretary of Commerce, the Chair of the Council on Environmental Quality, and the heads of other relevant agencies,” to submit a plan by the end of April. The plan must recommend steps the U.S. should take and include input from state, local, tribal, and territorial governments; agricultural and forest landowners; fishermen; and other key stakeholders.

Immediate tools Biden could use

Biden has some immediate tools at his disposal. He has placed a pause on new leases for oil and gas exploration on federal lands and waters, a move that could signal new environmental protections. Some western state senators and representatives have expressed concerns over that pause.

Biden also had ordered a 60-day review of former President Trump’s move to shrink the size of the Bears Ears and Grand Staircase-Escalante national monuments in Utah by two-million acres; The New York Times in 2017 described that action as “the largest rollback of federal land protection in the nation’s history.”

In addition, President Biden could create national monuments on federal public land through the Antiquities Act of 1906, enacted at that time to stem widespread looting of cultural sites across the American Southwest. Numerous presidents since then have exercised that authority. In 2009, for example, former President Bush established the Rose Atoll National Monument, a vast 13,436 square mile expanse of the Pacific Ocean.

During the January announcement of his plan to combat climate change, Biden called for establishment of a Climate Conservation Corps to mobilize people across the U.S. to participate in conservation projects that support the 30 by 30 goal. Biden ordered that Interior, the Department of Agriculture, and other agencies develop a strategy within 90 days to “to mobilize the next generation of conservation and resilience workers and maximize the creation of accessible training opportunities and good jobs.” The initiative is charged with seeking to “conserve and restore public lands and waters, bolster community resilience, increase reforestation, increase carbon sequestration in the agricultural sector, protect biodiversity, improve access to recreation, and address the changing climate.”

The corps, reminiscent of the Depression-era Civilian Conservation Corps, could help raise awareness of climate change challenges and, the administration says, provide people across the country with good paying jobs.

One key issue to be determined: Which 30 percent of land? In which states?

Achieving 30 by 30 will require action on numerous fronts. “A national program to enact 30 by 30 won’t just be a series of new national parks declared by the President, but will include things like national wildlife refuges, national monuments, state-level protected areas, conservation easements on private land, and co-management with tribal leadership,” wrote marine conservation biologist David Shiffman in Scientific American last October. “Local consultation and support will have to be part of it from the beginning, but it won’t be successful without support and leadership from the federal government.”

And it won’t be enough just to protect any land; it will matter significantly which 30 percent is protected. “Conserving a giant, undeveloped stretch of land where little lives and that no one wanted to develop anyway is not especially helpful to biodiversity conservation or climate resilience,” Shiffman wrote. At least some part of every major ecosystem needs to be protected, he wrote.

Privately held lands not excluded

Protecting lands held privately – for instance by individuals, families, or corporations, Shiffman wrote, also will be a critical part of the effort.

More than half of the country’s forests – critical carbon sinks, places that absorb more carbon dioxide than they release – are privately owned. U.C. Berkeley environmental science professors Arthur Middleton and Justin Brashares in the New York Times in December 2020 wrote that “private lands also connect our public lands, providing seasonal habitat for wide-ranging wildlife and clean drinking water, crop pollination, and flood control.” With about 12 percent of the privately land now meeting the 30 by 30 goals, they wrote, protecting the remaining 18 percent “means protecting an area more than twice the size of Texas.”

Maximizing carbon sequestration

What would it take to maximize the potential of natural lands as carbon sinks? An in-depth study of the challenge by a group of scientists in 2018 offered one perspective.

“Natural Climate Solutions for the United States,” published in Science Advances on November 14, 2018, identified 21 conservation, restoration, and improved land management interventions on natural and agricultural lands. The researchers estimated that these measures could potentially sequester the equivalent of 1.2 billion metric tons of carbon dioxide annually by 2025. That’s equal to 21 percent of current net annual emissions of the United States.

More than half of this potential – 63 percent – would come from increased carbon sequestration in plant biomass. Another 29 percent would come from increased carbon sequestration in soil; and 7 percent from avoided emissions of methane and nitrous oxide. Here are some highlights of the study:

• Reforestation is the largest single measure, with the potential to sequester 307 million metric tons of CO2 equivalent (CO2e) annually. Most of this potential occurs in the northeast (35%) and south central (31%) areas of the U.S. This potential can increase to 381 million metric tons of CO2e annually if all pastureland in historically forested areas is reforested. The authors noted that previous estimates have ranged widely from 208 to 1,290 million metric tons of CO2e annually. But the higher estimates require reforesting and afforesting (converting into forests) productive crop and pasture lands as well as natural grasslands.
• Another 267 million metric tons of CO2e annually can be sequestered by better managing forests on privately held land. Maximum potential can be achieved by extending harvest cycles and adopting other practices that reduce the impact of logging.
• Improved fire management on wildlands could result in sequestering 18 million metric tons of CO2e annually. This result includes restoring frequent, low-intensity, understory fires in fire-prone forest ecosystems to reduce the potential for catastrophic wildfires. “In the absence of improved fire management,” the authors wrote, “climate change is expected to continue to increase the frequency of high-severity fires and compromise the ability of forests to regenerate following these fires.”
• Avoiding conversions of forests for other uses could result in the sequestration of 38 million metric tons of CO2e annually. More than two-thirds of this potential, the authors wrote, is located in the Southern and the Pacific Northwest regions of the U.S. The authors noted that many of the places where forest conversion is occurring most rapidly are near urban areas, and also in agricultural areas such as the Central Valley of California.
• Avoiding conversions of grasslands to cropland can prevent emissions from soils and root biomass, resulting in the sequestration of 107 million metric tons of CO2e annually. Cropland expansion impacts grasslands much more than forests, and the higher rate of emissions from converted grasslands is due to a 28 percent loss of soil carbon from the top meter of soil.
• Growing cover crops on the five primary crops in the U.S. that do not currently use them (corn, soy, wheat, rice, and cotton), which cover more than 217 million acres nationwide, can result in the sequestration of 103 million metric tons of CO2e annually. Cover crops, grown when fields are normally bare, can result in increased carbon added to soils, improving nutrient management and overall soil health.
• Restoring tidal wetlands can also have an important impact on sequestering carbon, and the study estimates that 12 million metric tons of CO2e can be sequestered annually through restoration. About 27 percent of U.S. salt marshes are disconnected from the ocean and vulnerable to freshwater intrusion – which can result in big increases in methane emissions. Reconnecting salt marshes with the ocean, with culverts under roads and other infrastructure, can avoid such methane emissions.
• The study also identifies numerous other lesser measures, such as restoring peatlands, planting windbreaks and legumes in pastures, and better managing manure. Offshore, the authors also pointed to the importance of restoring seagrass. Every year, 1.5 percent of seagrass extent is lost, and about half of the carbon contained in biomass and sediment from disappearing seagrass beds escapes to the atmosphere, the authors estimated.

The potential is great in the U.S. and overseas to sequester carbon through natural solutions. The authors of the “Natural Climate Solutions” study noted that globally, natural climate solutions like the ones discussed above receive only 0.8 percent of public and private climate financing – despite their offering about 37 percent of potential mitigation needed through 2030.

As the Biden Administration pursues its agenda to fight climate change, the 30 by 30 goal will loom large. In their 2019 paper, “A Global Deal for Nature,” the authors argued that the most biologically diverse landscapes – tropical forests, for example – are also some of the most important carbon sinks. “It is no coincidence that some of the most carbon-rich ecosystems on land – natural forests – also harbor high levels of biodiversity,” they wrote. In ocean environments also, “biodiversity is part and parcel to the flux of atmospheric carbon to stored carbonates and deep ocean sediments.”

All of which adds up to the well-reasoned conclusion that striving toward 30 by 30 could benefit life on Earth and also help protect the climate that sustains it. The challenge ahead lies in matching the effort with the opportunity.

More to read:

“Land Management Practices for Carbon Dioxide Removal and Reliable Sequestration: Proceedings of a Workshop in Brief” (National Academies Press, 2018)

“NASA Satellites Help Quantify Forests’ Impacts on the Global Carbon Budget” (Jet Propulsion Laboratory, Feb. 3, 2021)

Numerous environmental groups have advocated for the 30 by 30 initiative, and some have developed detailed plans and other analyses that outline how it could be done. Here are a few:

Defenders of Wildlife: “Getting to 30 by 30: Guidelines for Decision-makers”

Natural Resources Defense Council: “Could Our Farms Become the World’s Great Untapped Carbon Sink?”

Center for American Progress: “The Plan for a 100 Percent Clean Future Must Include Saving Nature” (2020)

Center for American Progress: “Measuring Conservation Progress in North America” (2018)

Center for American Progress: “The Clogged Carbon Sink: U.S. Public Lands Are the Source of 4.5 Times More Carbon Pollution Than They Absorb” (2013)