United States Rejoins the Paris Agreement on Climate Change: Options for Congress
Updated February 25, 2021
United States Rejoins the Paris Agreement on Climate Change:
Options for Congress
On January 20, 2020, President Joe Biden accepted, on
A Party’s NDC must identify how the Party intends to abate
behalf of the United States, the Paris Agreement (PA), an
its GHG emissions, with a current time horizon of 2030.
international accord to address climate change for decades
(See text box.) Each Party decides its own pledge. All PA
to come. The acceptance took effect on February 19,
emissions targets are voluntary and nonbinding, although
2021—77 days after the United States’ withdrawal took
the PA contains provisions to encourage their achievement.
effect under the Trump Administration. The withdrawal
The UNFCCC requires reporting and review of GHG
took effect exactly four years after the United States first
emissions sources and sinks and other information,
became a Party to the PA under the Obama Administration.
differentiated by types of Parties. The PA led to an
enhanced transparency framework applicable to all Parties.
Congress may consider implications of U.S. participation in
The PA contains cooperative compliance mechanisms but
the PA along several dimensions, including foreign policy,
not formal sanctions.
economic, environmental, and legal. Although the President
holds constitutional authority for U.S. foreign policy, the
GHG Pledges in Selected NDCs
Senate may provide advice and consent, should the
(with date of most recent NDC GHG target)
President submit the PA to be a treaty under U.S. law.
Congress, by virtue of its own constitutional authorities, has
United States (2015, prior to withdrawal): Reduce GHG
options for shaping, funding, and conducting oversight of
emissions to 26%-28% below 2005 levels in 2025.
strategies—international and domestic—associated with
China (2015): Inter alia, by 2030, to peak its carbon dioxide
U.S. PA commitments. Congress may seek to consult with
(CO2) emissions; lower its CO2 emissions per unit of gross
the Administration on climate change and foreign policy,
domestic product (GDP) by 60%-65% below 2005 levels; and
among other objectives.
increase the non-fossil-fuel share of energy consumption to
around 20%.
What Is the Paris Agreement?
European Union (2020): A binding net domestic GHG
The PA exists under the United Nations Framework
emission reduction of at least 55% by 2030 compared with 1990.
Convention on Climate Change (UNFCCC). The United
India (2016): Inter alia, reduce GHG emissions per unit of GDP
States ratified the UNFCCC in 1992 with the advice and
by 33%-35% by 2030 from the 2005 level and reach 40% of its
consent of the Senate. In 2016, the United States accepted
the PA without requesting the Senate’s advice and consent;
cumulative installed electric capacity from non-fossil-fuel sources
by 2030.
the Department of State took the view that the PA was an
executive agreement containing no substantive, legal
Mexico (2020): Inter alia, reduce GHG emissions by 22% and
obligations for the United States beyond those already
black carbon emissions by 51% by 2030 below a business-as-
required by the UNFCCC. Under President Trump, the
usual (BAU) scenario or reduce GHG emissions up to 36% and
United States withdrew from the PA, citing concerns about
black carbon emissions up to 70% by 2030 below BAU by 2030,
fairness, costs of participating, and sovereignty. U.S.
conditioned on financial, technical, and other support.
private sector and bipartisan support subsequently has
grown for the PA, though there is not consensus on targets
Countries have long negotiated over what would constitute
or policies to meet them.
a “fair” distribution of effort under the UNFCCC. The
Under the UNFCCC, the United States and industrialized
strength of one Party’s GHG target compared with those of
Parties listed in “Annex I” took on specific commitments
other countries can be viewed from various perspectives of
for greenhouse gas (GHG) mitigation, financial resources,
fairness and level of effort. To illustrate, under existing
reporting, and review. The PA does not contain the
NDCs, China’s GHG emissions could grow to 2030,
bifurcation of commitments in the UNFCCC between
whereas the European Union’s (EU’s) GHG emissions
Annex I and developing country Parties. It established a
would fall. Nonetheless, China’s GHG emissions per
single, common set of obligations for all Parties (with
person would remain well below those of the United States.
flexibilities for the least capable). For example, China
China’s pledge would reduce its emissions per unit of GDP
agreed in the PA to the same binding requirements as the
more than the United States would under its 2015 pledge.
United States.
Foreign Policy and Diplomacy
A key requirement of the PA is that all Parties communicate
U.S. forceful negotiation, acceptance, withdrawal, and
“Nationally Determined Contributions” (NDC) every five
rejoining of the PA leaves legacies that are likely to shape
years, though the content of an NDC is not binding. Once a
future diplomacy. Some observers argue variously that the
Party, the United States must submit a new NDC; President
previous Administration’s withdrawal from the PA (1)
Biden aims to do this before Earth Day 2021 (April 22).
reduced U.S. standing in the world by making the United
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United States Rejoins the Paris Agreement on Climate Change: Options for Congress
States an international outlier on climate change; (2)
climate change would impose on people—costs of adapting
strengthened perceptions that the United States was
to climate change plus residual losses where anticipatory
withdrawing from its traditional position of leadership in
action does not fully avoid adverse impacts.
support of a rules-based international order; (3) created
space for China to increase its world leadership on climate
Trade could be affected by differences in Parties’ policies.
change and influence in international organizations and
China, South Korea, and European and other countries
processes; and (4) made the United States appear less
pursue investment toward low-GHG-emitting technologies
reliable as a negotiating partner.
in advanced energy, materials, electronics, vehicles, and
others they expect to provide future trade advantages.
Some observers argue that any adverse implications of
Several governments and the EU have discussed imposing
withdrawal were offset by benefits they perceive in avoided
border adjustments (i.e., tariffs) on producers that do not
domestic costs, increased energy independence, dominance
make similarly ambitious efforts to reduce GHG emissions.
in global fossil fuel markets, and U.S. sovereignty.
As the United States rejoins the PA, it may benefit from the
Financial Assistance
goodwill of those in the international community who
In the UNFCCC, higher-income Parties committed to
welcome the policy change. President Biden plans to host a
provide financial assistance to lower-income Parties to help
Climate Leaders Summit on Earth Day 2021 to promote
them meet their obligations and GHG targets. The decision
greater GHG reduction pledges before the next Conference
accompanying the PA to implement it extends to 2025 a
of the Parties in early November 2021. He also is pursuing
nonlegal goal from the 2009 Copenhagen Accord to
a host of further diplomatic and security initiatives.
mobilize jointly $100 billion per year to address the climate
finance needs of developing countries. The funds “may
Observers suggest U.S. withdrawal left a legacy that may
come from a wide variety of sources, public and private,
challenge the United States to regain the confidence of
bilateral and multilateral, including alternative sources.”
others and credibility for its commitments. Various
The U.S. federal government has not provided public funds
commenters indicate the Biden Administration may need to
since FY2016 appropriations, though private sources have
significantly increase U.S. ambition to reduce net GHG
contributed billions to climate-related finance. President
emissions; embody steps necessary to achieve U.S. GHG
Biden has charged the Secretaries of State and the Treasury
targets in durable regulations and new law; demonstrate
to lead development of a climate finance plan.
performance in accord with its strategy; and be consistent in
fulfilling unmet commitments on reporting and financing.
Potential Options for Congress
U.S. participation in the PA raises a number of options that
Environmental Considerations
Congress may consider, including
The PA contains a collective commitment to achieve
approximately net zero GHG emissions in the second half
consultation with the Department of State and/or the
of this century. The President has called for “net-zero
White House regarding new U.S. pledges under the
global emissions by mid-century or before.” The purpose in
UNFCCC and PA, and fulfilling currently unmet
the PA is to hold the GHG-induced increase in global
commitments on reporting and finance;
average temperature to well below 2o Celsius and to try to
limit it to 1.5oC. The pledges made in NDCs to 2030 are
oversight of Administration uses of existing statutory
intended as near-term steps in a multi-decadal process to
authorities to meet U.S. pledges, and whether there may
avoid adverse impacts on people, economies, and the
be benefits in a more comprehensive legislated strategy,
environmental systems on which societies depend.
to address efficiency and distributional impacts;
Many actions to reduce GHG emissions bring co-benefits—
provision of public funds, or incentives for private
positive effects beyond the intended climate change
financing, to assist low-income countries or particularly
benefits. An example is reduced health care costs and
impacted populations; and/or
mortality associated with air pollution. In many instances,
adopted GHG policies have been estimated to achieve co-
requests for assessments from the Administration of the
benefits that themselves exceed the costs of the GHG
ambitions, relative levels of effort, and performance of
reductions, without counting direct climate change benefits.
other Parties’ GHG mitigation, adaptation, technology,
The degree of co-benefits depends on policy design and
and financing associated with the PA.
depth of GHG reductions, as well as on the affected sectors.
See also CRS Report R44609, Climate Change: Frequently
Economy and Trade Implications
Asked Questions About the 2015 Paris Agreement, by Jane
Parties intended the PA to lay a path to long-term transition
A. Leggett and Richard K. Lattanzio; CRS In Focus
of the world’s economies toward “deep decarbonization”—
IF10397, International Climate Change Assistance: Budget
sustaining economic growth while delinking it from
Authority, FY2009-FY2019, by Richard K. Lattanzio.
emissions of CO2 and other GHGs. Such a transition is
generally expected to impose near- to medium-term costs,
with the magnitude and distribution (e.g., across sectors or
Jane A. Leggett, Specialist in Energy and Environmental
populations) depending on policy timing and design as well
Policy
as private investment. Some economists estimate the costs
IF11746
of deep decarbonization would be less than the costs
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United States Rejoins the Paris Agreement on Climate Change: Options for Congress
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https://crsreports.congress.gov | IF11746 · VERSION 5 · UPDATED