	Introduction

This report examines the implications for agriculture of the ongoing but inconclusive debate about global climate change. Whatever the current or future Congresses may do regarding climate legislation, interest in existing and prospective governmental and private sector responses will surely continue. Existing governmental climate change activities affecting or potentially affecting agriculture include the Environmental Protection Agency's (EPA) initiative under the Clean Air Act to address emissions of greenhouse gases (GHGs); U.S. Department of Agriculture (USDA) conservation programs that can encourage practices affecting agriculture's emissions or sequestration of GHGs; and provisions of law encouraging the use of biofuels. In the climate change debate, agriculture's role is multifaceted. Agriculture is both a source of several GHGs and a "sink" for absorbing carbon dioxide, the most common GHG, thereby partly offsetting emissions. Overall, agriculture is a comparatively modest source of U.S. GHG emissions: it accounts for approximately 7% of U.S. emissions, while transportation accounts for 27% and electricity generation for 35%. During the 111 th Congress, comprehensive climate change legislation passed the House and was reported by a Senate committee, but no comprehensive bill was enacted. One outcome was that the comprehensive climate change bills largely excluded agriculture from regulatory requirements, and another was that Congress through a funding bill excluded agriculture from certain EPA regulatory requirements concerning reporting of emissions (e.g., from manure management practices). One option would be to regulate agriculture and other sources of GHGs in order to mitigate or abate emissions. EPA Activities

Efforts have been underway in the Administration to develop policies and strategies to address GHGs and climate change. Two sets of actions by the EPA concerning GHG emissions have drawn stakeholders' attention. A number of agriculture stakeholders criticized the proposal. A key feature of H.R. Typically, conservation practices have been used for soil conservation and water quality improvement, not climate change abatement or mitigation. Strategies, technologies, and practices to reduce CH 4 and N 2 O emissions at the farm level are not mandated by federal policies. However, USDA and some states have started to focus additional attention on the potential for emissions reduction and carbon storage under certain existing programs. In general, conservation programs administered by USDA and state agencies encourage farmers to implement certain farming practices and often provide financial incentives and technical assistance to support their adoption. Results of the 2010 congressional elections have altered political dynamics in Congress on many issues, and leaders of both political parties have indicated that they currently do not plan to pursue comprehensive approaches to addressing climate change in the 112 th Congress, although some elements of previous proposals may move through the legislative process—for example, certain energy policy elements. How agriculture fits in these discussions has drawn interest in the past and likely will do so again.
This report examines the implications for agriculture of the ongoing but inconclusive debate about global climate change. In that debate, agriculture's role is multifaceted. Agriculture is both a source of several greenhouse gases (GHGs) and a "sink" for absorbing carbon dioxide, the most common GHG, thereby partly offsetting emissions. Overall, agriculture is a comparatively modest source of U.S. GHG emissions: it accounts for approximately 7% of U.S. emissions, while sectors such as transportation and electricity generation account for much larger shares. Agriculture's GHG emissions are principally in the form of methane and nitrous oxides emissions.
Whatever the current or future Congresses may do regarding climate legislation, interest in existing and prospective responses by government and others will continue. Administration efforts to develop policies and strategies to address GHGs and climate change have been underway for some time. Two actions by the Environmental Protection Agency (EPA) have drawn the attention of the agriculture industry. One is regulating emissions of GHGs under the Clean Air Act (CAA) and subsequent GHG emission standards for new motor vehicles which, in turn, trigger certain CAA permitting requirements. A second, related action is a rule to require reporting of GHG emissions by certain facilities. Regarding both, EPA took steps to focus on the largest emitters and ensure that few agricultural sources would be subject to new GHG requirements. Still, EPA's overall initiatives have been widely criticized, and the 111th Congress intervened through a funding bill to largely exclude agriculture from EPA's regulatory requirements. During the 111th Congress, the House passed a comprehensive climate change bill (H.R. 2454), and a Senate committee reported a companion (S. 1733). Although no legislation was enacted, both bills included provisions excluding agriculture from regulatory requirements and promoting agricultural practices to reduce or offset emissions from regulated sources.
Traditionally, practices such as conservation tillage have been used for soil conservation and water quality improvement, but their value for climate change abatement or mitigation is receiving increased attention. A number of strategies, technologies, and practices exist to reduce methane and nitrous oxides emissions at the farm level, but implementation faces financial and monitoring challenges.
Programs administered by the U.S. Department of Agriculture (USDA) provide financial incentives and technical assistance to encourage implementation of certain farming practices. While the focus of most programs is not on GHG emission reduction, USDA is giving greater attention to GHGs in administering its suite of existing programs.
Results of the 2010 congressional elections have altered political dynamics in Congress on many issues, and leadership of both political parties have indicated that neither currently plans to pursue comprehensive approaches to addressing climate change in the 112th Congress, although some elements of previous proposals may move through the legislative process. How agriculture fits in these discussions—both as a source of GHG emissions and contributions that the sector can make to mitigating climate change—has drawn interest in the past and likely will do so again.