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We use science to make change happen.
The Union of Concerned Scientists is a member-supported nonprofit that’s fighting for a safer and healthier world.
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Report
Accelerating Clean Energy Ambition
With concerted action, the US can meet its climate goals—and see huge benefits to the economy and public health.
Explainer
What is Climate Loss and Damage?
Wealthy, polluting nations should pay for climate damages.
Feature
2023 Annual Report
How did UCS perform over the last year?
Podcast
This is Science Thanks
Jess highlights her favorite reasons to be thankful for science in this season of gratitude.
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Accomplishments
Jonathan Schmer/Pexels
Cleaner Air in California as Trucks Rule Passes
UCS analysis and advocacy helped shape, strengthen, and pass a CA rule requiring large fleets of commercial trucks, delivery vans, and buses to transition to zero-emission vehicles by 2036—a huge win for cleaner air and reducing global warming emissions.