This report explores the potential for U.S. agriculture to achieve greenhouse gas (GHG) neutrality or become GHG-negative by integrating current and emerging practices across crop and livestock systems. The analysis identifies five major opportunity areas: soil carbon management, nitrogen fertilizer management, animal production and manure handling, crop production efficiency, and on-farm energy use. The report emphasizes the need for on-farm demonstrations, technical support, and policy incentives to overcome economic and technological barriers.

This commentary evaluates how agricultural science and technology can support implementation of the federal Climate 21 Project, which positions the U.S. Department of Agriculture as a central actor in national climate mitigation and resilience strategies. Agriculture and forestry are highlighted as the only major sectors capable of becoming net greenhouse gas sinks, offering substantial potential to help the United States reach net‑zero emissions by 2050 through soil carbon sequestration, improved nutrient management, reduced tillage, and strengthened crop and livestock systems.

The need to decrease concentrations of carbon dioxide and other greenhouse gases (GHGs) in Earth's atmosphere is one of the most pressing environmental issues. Agriculture both contributes to and is affected by climate change through its exchanges of GHGs. This report provides current information on carbon sequestration and GHG mitigation for various sectors of U.S. agriculture, including logistical and economic considerations for implementing emissions-reduction practices. It builds on the related 2004 CAST Task Force Report on climate change and greenhouse gas mitigation in agriculture.

Greenhouse gases (GHGs) are of increasing concern because of their potential role in promoting rapid and undesirable change in climate. Agriculture ironically serves as both a source and a sink for this increase in GHGs. This report analyzes agriculture's complex, pivotal role in this vitally important issue by considering policy options, implementation, and future monitoring and verification of GHG mitigation. The report outlines seven potential methods for agricultural mitigation of GHG concentrations.