Coastal vegetated ecosystems have long benefited coastal communities and fisheries, and in recent years have been recognized internationally for their significant capacity to sequester and store carbon (“blue carbon”)—at rates that surpass those of tropical forests. Yet these ecosystems are being converted rapidly. Current annual mangrove deforestation has been estimated to emit 240 million tons of carbon dioxide. For this reason, financing mechanisms to pay those tropical countries that have significant blue carbon resources to reduce greenhouse gas emissions from deforestation have been explored as a means to fund mangrove conservation. This report by the United Nations Environment Programme, the Abidjan Convention Secretariat, and GRID-Arendal explores the potential of international carbon finance mechanisms to help fund mangrove conservation along the coast of West, Central, and Southern Africa that is covered by the Abidjan Convention and examines the scale of economic benefits that this conservation might provide for the region, including benefits not always recognized in traditional assessments or valuations. 

To estimate the social cost of carbon dioxide for use in regulatory impact analyses, the federal government should use a new framework that would strengthen the scientific basis, provide greater transparency, and improve characterization of the uncertainties of the estimates, says a new report by the National Academies of Sciences, Engineering, and Medicine. The report also identifies a number of near- and longer-term improvements that should be made for calculating the social cost of carbon. 

In Nevada’s Diamond Valley, unsustainable groundwater pumping has decreased the aquifer’s water level, raising irrigators’ pumping costs and threatening the viability of existing wells and springs. Continued extraction in excess of natural recharge will trigger a legally required curtailment of water rights in the valley, which was recently declared a critical management area (CMA). The extent of rights curtailment is not mandated, but it could be as high as 64%, the amount required to reach the estimated natural recharge rate. The default policy for curtailment of water rights will occur according to the principle of prior appropriation, whereby rights are revoked in reverse order of their date of issuance. Rights granted most recently will be canceled first, and the revocation will proceed in order of increasing seniority until the government’s desired level of total water extraction is reached. Nevada law requires this intervention to occur within 10 years of the CMA declaration. This report analyzes the economic outcomes of sudden and alternative curtailment policies, using a hydro-economic model tailored to conditions in the region.

What are the most appropriate policies to facilitate regional bioenergy systems in furtherance of environmental, social, and economic objectives? A multi-year research project funded by the U.S. Department of Agriculture’s National Institute of Food and Agriculture has attempted to answer that question for the southeastern United States. Project analyses found few policies targeted to the upstream portions of the supply chain in the region, suggesting that efforts to encourage sustainable bioenergy markets should be cognizant of the dynamics of feedstock production and use. Investigation of bioenergy market participation identified non-production objectives, structural and social constraints, and market-related attributes that could influence market participation decision making. It also suggested that policies specific to individual markets might be more effective than uniform national initiatives in encouraging participation. Modeling of potential policies to facilitate development of regional bioenergy systems suggested that feedstock dynamics play a critical role in outcomes. A region-wide renewable portfolio standard—a policy characterized by few restrictions on the location of feedstock production and use—led to increases in forest carbon and decreases in greenhouse gas emissions at multiple scales. Forcing feedstock production and use to occur in particular locations might have the opposite outcome. The effectiveness of regional bioenergy systems will depend on the responsiveness of policy to social, economic, and resource conditions.

Successful landscape-scale forest conservation and management efforts must engage a wide variety of forestland owners. Owners of large areas of forestland (more than 10,000 acres) have a particularly important role to play in the attainment of landscape-scale goals. Their cooperation increases opportunities for attaining conservation benefits at significant scale. On March 8, 2016, a group of large private landowners was for the first time brought together with federal, NGO, and academic thought leaders to generate ideas for improving engagement on landscape-scale conservation goals. The dialogue was designed to identify barriers to and options for that engagement. These proceedings summarize the dialogue of meeting participants in addressing an “all lands” approach to conservation whereby landowners and stakeholders collaborate on identifying long-term, mutually beneficial goals for the landscapes they share. It includes a profile of large institutional forestland owners and details the results of a survey conducted to measure their current engagement in conservation activities. Participants identified barriers to engaging large forest landowners in conservation. They include the absence of an inclusive vision for the future of forest management, insufficient leadership for building diverse coalitions to address forest threats, lack of alignment of existing federal programs with respect to large ownership structures, limited understanding of the public benefits provided by large privately owned forests, and lack of markets to sustain these benefits. Participants recognized the need to define a shared conservation vision, to build leadership for a broad coalition of stakeholders, and to execute a national strategy recognizing the value of and providing incentives for large private landowners to cooperatively address forest threats. Much discussion centered on building the business case for conservation and on recognizing new values and expanding markets. Participants also considered opportunities for aligning the incentive-based approaches of funding agencies with the needs and interests of forestland owners. A steering committee was formed to consider developing specific strategies to incentivize engagement of large forestland owners and to work toward a collaborative vision for attaining conservation objectives across varied ownerships.

This study in Applied Energy explores whether creation of localized bioenergy markets near existing military installations in the southeastern United States could address military renewable energy generation objectives while reducing urban encroachment. To stimulate creation of these markets, it models the use of public–private partnerships, pairing stable installation demand with stable supply from surrounding landowners. It employs the SubRegional Timber Supply (SRTS) model and the Forest and Agricultural Sector Model with Greenhouse Gases (FASOMGHG) to assess how markets influence forest and agriculture land use, renewable energy production, and greenhouse gas (GHG) mitigation at the regional and national levels. When all selected installations increase bioenergy capacity simultaneously, it finds increased preservation of forest land area, increased forest carbon storage in the region, and increased renewable energy generation at military installations. Nationally, however, carbon stocks are depleted as harvests increase, increasing GHG emissions even after accounting for potential displaced emissions from coal- or natural gas-fired generation. Increasing bioenergy generation on a single installation within the Southeast has very different effects on forest area and composition, yielding greater standing timber volume and higher forest carbon stock. In addition to demonstrating the benefits of linking two partial equilibrium models of varying solution technique, sectoral scope, and resource detail, results suggest that a tailored policy approach may be more effective in meeting local encroachment reduction and renewable energy generation objectives while avoiding negative GHG mitigation consequences.

Anaerobic digesters (ADs) can reduce waste volumes and capture methane emissions from concentrated animal feeding operations (CAFOs), but their adoption rate is low because their cost is high relative to other forms of waste management. Farmers who use ADs can attempt to sell carbon credits and nutrient credits as well as renewable electricity certificates (RECs) generated by on-site electricity production from captured methane. These credits and RECs can be used as marketable “offsets” that buyers can use to help meet their greenhouse gas and nutrient pollution reduction goals. One issue that arises is whether a single operation can sell into multiple credit markets by “stacking” credits—that is, receiving multiple environmental payments to finance the conversion to AD technology. This practice introduces the possibility that some credits might be “non-additional”—i.e., produce no incremental pollution reductions—and thus be suspect pollution offsets. Non-additionality in environmental credit stacking occurs when multiple payment streams do not produce incremental pollution reductions, thus allowing the credit buyer to pollute more than is being offset by the AD project. A possible solution to the stacking problem may be to allow stacking of all credits available at the time of AD installation, but to prohibit any further stacking if new credit streams become available after installation. This is a revised paper that was originally published in 2015.

In the United States, land carbon offsets nearly 15 percent of economy-wide greenhouse gas emissions, equivalent to half of emissions from the transportation sector. However, the future of this sizable "carbon sink" is uncertain. The latest U.S. assessments disagree on whether land will be a sink or a source in the coming decades, which could make all the difference in whether future climate targets are reached. Despite significant research, a complete understanding of policy or market tools capable of bending the trajectory of the carbon sink remains elusive. This report by Forest Trends and the Nicholas Institute for Environmental Policy Solutions—the first product of the Land Carbon Policy Roadmap Initiative—launches a process for understanding the most significant drivers of land carbon change and the policy tools critical for managing land carbon into the future. It offers new analysis to support a long-term roadmap for enhancing the U.S. land carbon sink, ensuring that healthy and productive landscapes contribute to greenhouse gas reduction goals.

This paper reviews annual government spending on Canadian agriculture that attempts to stabilize and enhance farm incomes. Since 2010, two-thirds of the $3 billion spent on agriculture went into stabilization programs to support farm incomes. This level of support raises questions about the environmental consequences of enhanced agricultural production. Canadian government expenditures on environmental initiatives in agriculture, as a share of farm income, are more than 10 times smaller than those in the United States and the European Union. Canadian stabilization programs have modest impacts on production, but chemical and fertilizer input use may be higher than in the programs' absence. One possible course of action is to introduce cross-compliance between program payments and environmental objectives. However, there are no requirements that Canadian producers receiving support comply with environmental standards. Although cross-compliance could be considered in the Canadian context, policies that directly target specific environmental issues in agriculture may have greater impact.

The substitution of biogas, an energy source derived from biological feedstock, for fossil natural gas (NG) can mitigate the build-up of greenhouse gases in the atmosphere, making it an attractive renewable energy source in a carbon-constrained future. Although upgraded, pipeline-quality biogas can augment the NG market supply in the United States, researchers and energy industry experts have little studied its long-term potential. This article estimates (1) levelized costs of energy for biogas production facilities operating with landfill waste, animal manure, wastewater sludge, and biomass residue feedstocks; (2) feedstock and technology pathway-specific biogas supply functions; and (3) the aggregate national biogas supply potential for the United States by 2040. Under a range of specified assumptions, generation of biogas could be expanded to approximately 3–5 percent of the total domestic NG market at projected prices of $5–6/MMBtu; the largest potential source comes from thermal gasification of agriculture and forest residues and biomass. As market signals have not spurred widespread adoption of biogas in the United States, policy incentives similar to those used in the European Union may be necessary to increase its production and use. Bioenergy policy in the European Union and the resulting market penetration achieved there provides important lessons for how biogas markets in the United States can overcome barriers to market expansion and, in doing so, provide substantial climate mitigation benefits.