Global greenhouse-gas emissions have been growing at an alarming rate in 2018, with scientists comparing the pace to a “speeding freight train,” The New York Times reports. Two studies published Wednesday warn that the rapid increase of carbon-dioxide emissions will likely bring about the most severe consequences of global warming sooner than expected. “We’ve seen oil use go up five years in a row,” Rob Jackson, a professor of earth system science at Stanford who authored one of the two studies, told the Times. “That’s really surprising.” The new research, published by the Global Carbon Project, predicts that carbon emissions worldwide will increase by 2.7 percent this year. Scientists also said the unexpected surge in oil consumption—which has offset progress made by the sale of electric vehicles—is partly to blame.