Global heat, greenhouse gases and sea levels all climbed to record highs last year, making 2015 the worst in modern times across a range of key environmental indicators, international scientists said Tuesday. A dire picture of the Earth’s health is painted in the State of the Climate report, a peer-reviewed 300-page tome that comes out once a year and is compiled by 450 scientists from around the world. The record heat that the planet experienced last year was driven partially by global warming, and was exacerbated by the ocean heating trend known as El Nino, it said.