It is just after 8.30am on a snowy February morning when Vidar Helgesen, Norway’s climate and environment minister, steps out of his home in Oslo, dodging frozen puddles to reach his waiting ministerial car. It seems improbable on this glacial day but in less than 24 hours time, Mr Helgesen will have flown across the world to Indonesia’s sweltering capital, Jakarta, on a trip that will take him to a remote patch of Borneo rainforest…