The Rise of the Climatarian

Determining exactly how to do that when it comes to your diet, however, isn’t easy. While many climatarians aren’t vegetarians, since they believe that chicken or lamb are much better choices than beef, some eschew meat altogether since vegetables overall have a lower carbon footprint.

Mike Tidwell, 59, the director of the Chesapeake Climate Action Network, avoids almonds and pistachios because they require large amounts of water to grow. “The chronic droughts in California, brought on by climate change, have made me eat fewer foods that are very water intensive,” said Mr. Tidwell, who lives in Takoma Park, Md.

Maggie Vlasaty, 22, a marketing associate in Minneapolis, avoids beef, pork, and most other meats and seafood. She also doesn’t eat food from brands that support oil drilling. Before she goes to a restaurant, she looks carefully over the menu to see what she should order.

“If I don’t have time to do that, it becomes a stressful event for me,” Ms. Vlasaty said. “I’ve also adapted to going to friends’ houses or parties by usually eating before heading out.”

Shelbi Storme, 28, a sustainability blogger in San Antonio, Texas, started avoiding red meat when she learned how much water it takes to produce a single hamburger: 150 gallons for a quarter-pounder, according to the United States Geological Survey. But living in the state with bragging rights to the most cattle in America, it’s tricky for her to navigate meal options — especially when she goes out with friends.

Ms. Storme often uses the app Happy Cow to find vegetarian-friendly spots, but her friends aren’t always so accommodating.