Earth’s surface will almost certainly not warm up four or five degrees Celsius by 2100, according to a study released Wednesday which, if correct, voids worst-case UN climate change predictions. A revised calculation of how greenhouse gases drive up the planet’s temperature reduces the range of possible end-of-century outcomes by more than half, researchers said in the report, published in the journal Nature. “Our study all but rules out very low and very high climate sensitivities,” said lead author Peter Cox, a professor at the University of Exeter. How effectively the world slashes CO2 and methane emissions, improves energy efficiency,...