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Throughout President Trump's overseas trip this week, he's been getting an earful about climate and how important the Paris climate agreement is. Many foreign leaders say the U.S. should not abandon it, and President Trump tweeted this morning that he will make a final decision next week. But as NPR's Christopher Joyce reports, staying in or out of that Paris deal may not make that much difference.
CHRISTOPHER JOYCE, BYLINE: Pope Francis told President Trump to stick with the Paris agreement, so did France's newly elected president, Emmanuel Macron. The agreement they're so passionate about sets in motion a global effort to reduce emissions of greenhouse gases that warm the planet. Trump says it's a bad deal for the U.S. economy. Nearly 200 other nations say it's a good deal for the planet. But climate experts point out that emissions in the U.S. are already going down without the Paris deal.
KATE LARSEN: The U.S. has successfully bent its greenhouse gas emissions curve. And we are going to continue to reduce emissions over the next 10 years, likely regardless of Trump policy.
JOYCE: That's Kate Larsen with the Rhodium Group, which does research on climate economics. Emissions in the U.S. have declined by about 12 percent since 2005. A new study by Rhodium says that decline is likely to continue.
LARSEN: With current policy, including everything that states have committed to do and what President Trump has indicated he is likely to roll back, we are on a path to reduce emissions below 2005 levels by about 15 to 17 percent in 2020.
JOYCE: Larsen and other energy economists say a big part of that is due to decisions made by companies, especially those that make electricity.
LARSEN: A lot of that is switching from coal to gas in the power sector and now increasingly from coal to gas to renewables. And that's a trend that we don't see stopping anywhere in the near future.
JOYCE: In effect, Larsen says, what happens over the next few years has already been set in motion. The picture beyond 2020, though, gets cloudy. By then, whatever the Trump administration does to dismantle climate regulations would have kicked in. Economist Marc Hafstead says that if the economy grows faster as well, the downward emissions trend could stall by 2025.
MARC HAFSTEAD: And my analysis was, under the best-case scenario, we'd come in somewhere around 10.
JOYCE: A 10 percent drop in emissions. President Obama promised to cut emissions well over twice that under the Paris agreement. In the end, though, the decision about staying in or leaving the Paris agreement is not just about hitting numerical targets. Hafstead, who's with Resources for the Future, says what the U.S. does sends a message to the rest of the world.
HAFSTEAD: Exiting Paris could potentially have political ramifications to the extent that our pulling out of the agreement is going to cause other countries to do less.
JOYCE: Which could have far greater consequences for global warming than how far off the climate mark the U.S. ends up.
Christopher Joyce, NPR News.
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