There is increased interest in a carbon tax in the United States (U.S.) and policy makers, farmers, and other stakeholders need to understand the various economic and environmental aspects of such a policy on agriculture. A global agricultural simulation model assesses changes in production, commodity prices, and trade resulting from a U.S. carbon tax. In addition, greenhouse gas (GHG) emissions from land-use change are quantified to evaluate the possible unintended consequence of increasing emissions in the rest of the world. Three U.S. carbon tax scenarios are evaluated ranging from $15–$144 per metric ton of carbon dioxide equivalent (t⁻¹ CO₂-e) and covering a 10-year projection period. The results show that the production cost for corn and soybeans increase by a maximum of 32.6% and 22.4%, respectively at a carbon tax of $144 t⁻¹ CO₂-e. The production cost increase is compensated in part by an increase in commodity prices. Hence, the decrease in net returns for corn, soybeans, and wheat is 11.4%, 8.7%, and 11.0%, respectively, in the scenario with the highest carbon price. U.S. exports decrease for major commodities such as corn (24.9%), sorghum (20.5%), and wheat (8.7%). Barley, soybeans, and sunflower see an increase in exports of 1.2–8.8%. These changes in trade patterns also result in a re-allocation of land-use in the rest of the world leading to a slight increase in global GHG emissions from land-use change representing 1.8% of total U.S. emissions in 2017. The increase in emissions is small compared to the overall projected reduction from the carbon tax. Policy makers need to be cognizant of leakage in terms of land-use change and that measures must be taken to avoid expansion into carbon rich native vegetation.

美国（美国）对碳税越来越感兴趣，决策者，农民和其他利益相关者需要了解这种农业政策的各种经济和环境方面。全球农业模拟模型评估了美国碳税导致的生产，商品价格和贸易的变化。此外，对土地利用变化产生的温室气体（GHG）排放进行了量化，以评估世界其他地区排放增加可能产生的意外后果。评估了三种美国碳税方案，每公吨二氧化碳当量（t ^-1 CO ₂为15–144美元）-e），涵盖10年的预测期。结果表明，在144 t ^-1 CO ₂的碳税下，玉米和大豆的生产成本分别最多增加了32.6％和22.4％。-e。生产成本的增加部分由商品价格的上涨来弥补。因此，在碳价格最高的情况下，玉米，大豆和小麦的净收益分别下降11.4％，8.7％和11.0％。美国主要商品的出口减少，例如玉米（24.9％），高粱（20.5％）和小麦（8.7％）。大麦，大豆和向日葵的出口增长了1.2％至8.8％。贸易模式的这些变化还导致世界其他地区土地使用的重新分配，导致土地使用变化带来的全球温室气体排放量略有增加，占2017年美国总排放量的1.8％。排放量增加与预计的碳税削减总额相比，这个数字很小。