"The greenhouse gases (GHGs) in the atmosphere trap radiant energy, warming earth’s surface
and oceans. Scientific assessments conclude that GHGs very likely have been the main driver of
warming of the earth’s lower atmosphere since 1979. The most recent global assessment
projected that surface temperature would continue to rise until at least mid-century even under
the lowest GHG emission scenarios considered. A range of actions to mitigate GHG emissions
and the risks of climate change (i.e., for adaptation or resilience) are under way or being
developed on the international, national, and subnational levels. U.S. federal policymakers and
stakeholders have different viewpoints regarding what, if anything, to do about future climate
change and related impacts.
Brief History of U.S. Climate Policy
Historically, the United States has demonstrated varying approaches and intent with regard to addressing climate change
generally and to participating in GHG abatement under the 1992 United Nations Framework Convention on Climate Change
(UNFCCC). International negotiations led to, among other agreements, the adoption of the Paris Agreement (PA) in 2015.
President Obama accepted the PA without submitting it to the Senate for advice and consent, and the United States became a
Party to the agreement when the PA entered into force in 2016. President Trump announced U.S. withdrawal from the PA in
June 2017, which became effective in November 2020. President Biden again accepted the PA, and the United States became
a Party on February 19, 2021.
U.S. climate change policy has involved actions implemented under various legal authorities. Prior to 2007, the federal
government implemented voluntary programs to address climate change and regulatory programs that indirectly limited GHG
emission increases from vehicles, appliances and equipment, and buildings. A shift toward direct regulation of GHG
emissions occurred following the 2007 decision in Massachusetts v. EPA, in which the Supreme Court found that the
Environmental Protection Agency (EPA) has authority to regulate GHG emissions from motor vehicles as air pollutants
under the Clean Air Act. EPA subsequently issued rules to limit GHGs from various sources, although not all have been
implemented. State and local governments have also taken a variety of actions, including emission controls on power plants
and vehicles and building codes.
U.S. Legislation
Members of Congress have historically expressed a range of perspectives regarding climate change issues. Legislative
proposals have included carbon pricing frameworks (e.g., carbon taxes or cap-and-trade programs), sectoral approaches such
as a clean energy standard, research funding or tax policies that support GHG-abating technology development and
deployment, efforts to increase adaptation, and international cooperation. On the other hand, introduced resolutions have
expressed that the multisector carbon pricing approaches are not in the economic interests of the United States. Votes on
comprehensive climate change policy have been relatively rare in either chamber of Congress. Examples of enacted
legislation involving climate change issues include tax incentives to promote renewable energy sources and carbon capture
and sequestration efforts.
Executive Branch Approach to Climate Change
President Biden announced a new GHG target for the United States: to reduce net GHG emissions by 50%-52% below 2005
levels by 2030. The Administration has also centralized executive branch organizations to identify and coordinate climate related actions, and issued directives with a view toward decisions that support meeting the Administration’s GHG reduction
targets.
Issues for Congress
Congress may consider issues concerning U.S. GHG targets, policy approaches, and funding. For example, U.S. participation
in the PA raises issues that Congress may consider concerning the ambition, relative level of effort, and performance of other
parties’ GHG mitigation, adaptation, technology, and financing associated with the PA. Differences in parties’ GHG policies
may have implications for trade. For example, several national governments and the EU have discussed imposing border
carbon adjustments(i.e., tariffs) on imported goods from countries that do not make similarly ambitious efforts to reduce
GHG emissions..."
Climate change policy