America’s carbon dioxide emissions rose by 3.4 percent in 2018, the biggest increase in eight years, according to a preliminary estimate published Tuesday. Strikingly, the sharp uptick in emissions occurred even as a near-record number of coal plants around the United States retired last year, illustrating how difficult it could be for the country to make further progress on climate change in the years to come, particularly as the Trump administration pushes to roll back federal regulations that limit greenhouse gas emissions.

Scott Pruitt, the head of the Environmental Protection Agency, rented a residence in Washington in 2017 that was partly owned by the wife of a top energy lobbyist whose firm, according to disclosure forms, conducted business before the E.P.A. that same year.