Associated Press: Climate change has emerged as one of the most urgent threats to polar bears as wildlife officials from the five Arctic countries meet in Norway this week to discuss how to protect the vulnerable species. The three-day conference that opens Tuesday in the northern Norway city of Tromsoe is the first since 1981 to bring together Norway, Danish-held Greenland, the United States, Canada and Russia to review a 36-year-old accord on protecting the world’s estimated 20,000-25,000 polar …