Guardian: “You are choosing the path focused on corporate greed,” climate scientist James Hansen has told carbon traders in a open letter which he and climate activists attempted to deliver to a carbon trading conference in New York today. In below-freezing temperatures, climate change campaigners gathered at midday at the Irish Hunger Memorial in Vesey Park, near the Embassy Suites Hotel where the conference is being held, to hear Hansen read parts of his open letter. Tomorrow there will be …