This review of taxation in agriculture in 35 OECD countries and emerging economies outlines the diversity of tax provisions affecting agriculture, provides an overview of cross-country differences in tax policy, and confirms the widespread use of tax concessions specifically for agriculture, although their importance and modalities differ across tax areas and countries.

The U.S. Congress charged the National Academies with conducting a review of the Internal Revenue Code to identify the types of and specific tax provisions that have the largest effects on carbon and other greenhouse gas emissions and to estimate the magnitude of those effects. To address such a broad charge, the National Academies appointed a committee composed of experts in tax policy, energy and environmental modeling, economics, environmental law, climate science, and related areas. For scientific background to produce Effects of U.S. Tax Policy on Greenhouse Gas Emissions, the committee relied on the earlier findings and studies by the National Academies, the U.S. government, and other research organizations. The committee has relied on earlier reports and studies to set the boundaries of the economic, environmental, and regulatory assumptions for the present study. The major economic and environmental assumptions are those developed by the U.S. Energy Information Administration (EIA) in its annual reports and modeling. Additionally, the committee has relied upon publicly available data provided by the U.S. Environmental Protection Agency, which inventories greenhouse gas (GHG) emissions from different sources in the United States. The tax system affects emissions primarily through changes in the prices of inputs and outputs or goods and services. Most of the tax provisions considered in this report relate directly to the production or consumption of different energy sources. However, there is a substantial set of tax expenditures called "broad-based" that favor certain categories of consumption-among them, employer-provided health care, owner-occupied housing, and purchase of new plants and equipment. Effects of U.S. Tax Policy on Greenhouse Gas Emissions examines both tax expenditures and excise taxes that could have a significant impact on GHG emissions.

vate, operate, or manage a farm for profit, either as owner or tenant. A farm includes livestock, dairy, poultry, fish, fruit, and truck farms. It also includes plantations, ranches, ranges, and orchards and groves. This publication explains how the federal tax laws apply to farming. Use this publication as a guide to figure your taxes and complete your farm tax return. If you need more information on a subject, get the specific IRS tax publication covering that subject. We refer to many of these free publications throughout this publication. See chapter 16 for information on ordering these publications. The explanations and examples in this publication reflect the Internal Revenue Service's interpretation of tax laws enacted by Congress, Treasury regulations, and court decisions. However, the information given does not cover every situation and is not intended to replace the law or change its meaning. This publication covers subjects on which a court may have rendered a decision more favorable to taxpayers than the interpretation by the IRS. Until these differing interpretations are resolved by higher court decisions, or in some other way, this publication will continue to present the interpretation by the IRS.

To understand the impacts of support programs on global emissions, this paper considers the impacts of domestic subsidies, price distortions at the border, and investments in emission-reducing technologies on global greenhouse gas (GHG) emissions from agriculture. In a step towards a full evaluation of the impacts, it uses a counterfactual global model scenario showing how much emissions from agricultural production would change if agricultural support were abolished worldwide. The analysis indicates that, without subsidies paid directly to farmers, output of some emission-intensive activities and agricultural emissions would be smaller. Without agricultural trade protection, however, emissions would be higher. This is partly because protection reduces global demand more than it increases global agricultural supply, and partly because some countries that currently tax agriculture have high emission intensities. Policies that directly reduce emission intensities yield much larger reductions in emissions than those that reduce emission intensities by increasing overall productivity because overall productivity growth creates a rebound effect by reducing product prices and expanding output. A key challenge is designing policy reforms that effectively reduce emissions without jeopardizing other key goals such as improving nutrition and reducing poverty. While the scenario analysis in this paper does not propose any particular policy reform, it does provide an important building block towards a full understanding the impacts of repurposed agricultural support measures on mitigation of greenhouse gas emissions and adaptation to climate change. That full analysis is being undertaken in subsequent work, which will also take account of land-use change and alternative forms of agricultural policy support to align objectives of food security, farmers’ income security, production efficiency and resilience, and environmental protection.