Scientists are having a hard time overlooking their own air travel emissions. Kim Cobb, a climate scientist at the Georgia Institute of Technology, has curbed her air travel by 75 percent. “I really started thinking about my carbon footprint after Trump was elected,” she said. “Doing my climate science and donating to the right candidates was never going to be enough, even if you took that to scale.” She created a spreadsheet to track her personal carbon footprint and found that flying formed the dominant share of her emissions. “By the end of 2017, 85 percent of my carbon footprint was related to flying,” she said.