Policy synergies between nutrient over-enrichment and climate change

Surplus nitrogen from agricultural production is a leading cause of water quality problems in the U.S. It is also a source of nitrous oxide, the largest category of greenhouse gas emissions from agriculture. Any reduction in the amount of nitrogen lost from farming practices would produce significant benefits for both water quality and climate protection. Using a model of the U.S. agricultural sector we adapted to explore water quality and climate issues, we evaluate a variety of policy options for their impact on farm income and the environment. We find that policies to create markets for reductions in nitrogen lost to water or greenhouse gas emissions from agriculture would increase farm income while producing cost-effective environmental benefits.