"Today, the Trump Administration officially left the Paris Climate Change Agreement," tweeted President-elect Joe Biden on November 4, 2020. "And in exactly 77 days, a Biden Administration will rejoin it."
On April 22, 2016—Earth Day—then–President Barack Obama signed the Paris accord, treating it as an executive agreement rather than a treaty requiring Senate approval. Recognizing that unabated man-made climate change would likely become a significant problem for humanity as the century advances, the Paris Agreement aims to limit the increase of global average temperature to less than 2 degrees Celsius above its pre-industrial level. Under the agreement's provisions, signatories submit their plans, called nationally determined contributions (NDC), to the United Nations. The pledges are voluntary and nonbinding.
Back in 2010, the Obama administration promised to reduce U.S. emissions of greenhouse gases to 17 percent below their 2005 levels within a decade. In 2015, the administration submitted its NDC, committing to a cut of 26–28 percent compared to the same baseline by 2025. Over the longer term, the administration pledged to reduce U.S. emissions by 80 percent from their 2005 levels by 2050. Under Obama's 2015 Clean Power Plan, emissions from electric power generation were supposed to fall 30 percent by 2025.
President-elect Biden's $2 trillion plan for a "clean energy revolution and environmental justice" is even more aggressive. By 2035, no electric power would be generated by burning fossil fuels, and the U.S. would commit to zero net emissions of greenhouse gases by 2050.
President Donald Trump issued numerous executive orders to cancel Obama's climate change programs and regulations. Biden no doubt will issue executive orders to re-establish and expand many of the Obama administration's top-down, centralized climate programs. These include raising vehicle fuel economy standards, restoring the Clean Power Plan to make deep cuts in emissions from electricity generation, imposing stricter energy efficiency standards on appliances and buildings, and banning fossil fuel production on federal lands.
Where do U.S. emissions of greenhouse gases stand compared to Obama's pledges? According to a July report by the Rhodium Group consultancy, U.S. emissions have declined by 21 percent from their 2005 baseline. In other words, the U.S. has more than met the Obama administration's promised reduction goal for 2020. But that decline was largely due to a market-driven shift from coal to natural gas for electricity generation and to the economic disruptions caused by the COVID-19 pandemic, rather than to specific policies aimed at reducing greenhouse gas emissions.
What about Obama's NDC pledge to cut emissions by 26–28 percent as of 2025? In a scenario where no new policies are adopted and the economy makes a quick post-pandemic recovery, the Rhodium analysts believe U.S. emissions will remain essentially flat at 20 percent below their 2005 levels. If the recovery is slow, the analysts say, U.S. greenhouse emissions in 2025 would be about 27 percent below their 2005 levels. New policies from the Biden administration are a given, however.
The next U.N. climate change meeting was postponed for a year due to the pandemic. It will convene in November 2021 in Glasgow, Scotland. Paris Agreement signatories are supposed to submit more-ambitious NDCs at that meeting. In his climate change plan, Biden aims to "push the rest of the world to raise their ambitions alongside the United States."
How ambitious will those targets be? The Center for American Progress, a think tank from which the Biden administration probably will draw many staffers, argues that the U.S. should commit to a 2030 goal of cutting its greenhouse gas emissions by 43 percent below their 2005 levels.