President Donald Trump said Wednesday he will announce whether the U.S. will withdraw from the Paris Agreement on climate change on Thursday.
With White House sources indicating he's leaning toward an exit, here's what you need to know about the international effort and what Trump's decision could mean for the environment.
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What is the Paris agreement?
The Paris Agreement is a deal reached between 195 countries to gradually reduce emissions that cause climate change in order to prevent a major increase in the global temperatures that could raise sea levels, spark major droughts, and lead to more dangerous storms.
The agreement, which was negotiated in 2015 and took effect in November 2016, was spurred by the overwhelming global scientific consensus that rising global temperatures over the last several decades are caused by man-made activity. The United Nations Intergovernmental Panel on Climate Change, which pools scientific research from around the world, concluded that emissions caused were "extremely likely to have been the dominant cause of the observed warming since the mid-20th century" with more than 95 percent confidence.
Climate change is already impacting the planet, but the specific goal of the Paris Agreement is to prevent the planet from warming by more than 2 degrees Celsius (3.6 degrees Fahrenheit), which scientists warn could have especially damaging consequences.
What does the U.S. have to do?
The agreement, which is not a binding treaty, calls on countries to make voluntary national pledges to reduce emissions and provide periodic updates on their progress.
President Barack Obama committed America to a goal of lowering emissions by 26 percent to 28 percent below 2005 levels by 2025. These targets aren't fixed forever, though, and the broad aim is to increase them over time.
The agreement also hinges on developed countries like the United States, whose economies have contributed more emissions historically, helping to finance developing countries' transition to cleaner forms of energy. The plan is to raise $100 billion a year through a mix of public and private sources.
On the U.S. side,
Why would Trump want out?
There are a number of aspects of the climate deal that run counter to the president's worldview.
One, Trump does not accept the dominant scientific consensus on climate change and has a penchant for conspiracy theories that cast experts like researchers, doctors, or government agencies in the role of villain. He has repeatedly tweeted and said in campaign speeches
Two, Trump is a skeptic of international agreements and institutions in general, which he often complains tie America down with obligations that don't provide enough concrete benefits in return. In addition to the Paris Agreement, Trump has rattled allies by criticizing trade agreements and military alliances.
Three, Trump is not a fan of the regulations and spending that the previous administration proposed to meet its goals, which he warns will reduce economic growth. He appointed a prominent climate skeptic to run the Environmental Protection Agency, Scott
These objections aren't unique to Trump. Many conservatives opposed the Paris Agreement on similar grounds and have pushed him to withdraw.
What happens if the US withdraws from the agreement?
The agreement won't fall apart overnight. Already, reports suggest China and the European Union are prepared to publicly recommit to the agreement with or without the United States. Some experts say China appears to
Trump also can't technically withdraw from the agreement until November 2019. It's possible he could speed things up by abandoning the underlying Senate-approved climate treaty that the agreement is linked to.
It's an open question whether the United States will hit its Paris emissions target with or without the agreement. The economy is already moving away from carbon-heavy energy sources like coal in favor of cleaner natural gas and increasingly affordable renewable energy. Trump's
It's also notable that some of the largest companies in industries that would be impacted most by climate regulation are supporting the Paris Agreement. For example, ExxonMobil, the oil giant whose former CEO Rex Tillerson is now Secretary of State, has publicly lobbied the White House not to withdraw.
"I actually think we might meet our target," J. Timmons Roberts, an environmental studies professor at Brown University, told NBC News. "The technology is making the choices easier for people more quickly than expected."
But supporters of the agreement warn the United States would, at a minimum, damage its relationship with close allies by bolting and cede more global influence to rivals like China. In a worst-case scenario, the move would discourage developing nations from taking further steps to limit emissions, potentially hampering efforts to reduce emissions before dangerous temperature increases are locked in.
A lot of this depends on expectations. If participating nations and industry leaders assume the United States exit is only a temporary bump and that future presidents will return to the table and pursue similar policies as Obama, that could also make them reluctant to make decisions based on Trump's decision alone.
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