- [“Scientists... calculated just what would happen if every American made one dietary change: substituting beans for beef. They found that if everyone were willing and able to do that—hypothetically—the U.S. could still come close to meeting its 2020 greenhouse-gas emission goals](https://www.scientificamerican.com/article/us-may-come-close-to-2020-greenhouse-gas-emission-target/), pledged by President Barack Obama in 2009.”