 They once opposed the Environmental Protection Agency in a resolution which came out against enforcing stricter smog and soot limits.The conference members felt that the stricter standards for ozone and fine particles would have hampered the economies of many municipalities, especially those that are steel-, automobile- and fossil fuel-intensive.The U.S. Conference of Mayors also houses the Mayors Climate Protection Center, created in 2007 to provide support mayors in efforts to reduce global warming in American cities.