The renewed upward march of global carbon emissions is worrying and a big step backwards in the fight against climate change, according to BP. Emissions rose 1.6% in 2017 after flatlining for the previous three years, which the British oil firm said was a reminder the world was not on track to hit the goals of the Paris climate deal. Renewable power generation grew by 17% last year, led by wind and followed by what BP called “stunning” growth in solar. But strong economic growth led to above-average energy demand, coal use bounced back in China and efficiency gains slowed down, causing emissions to jump, the company’s annual statistical review of world energy found.