Agence France-Presse: US President Barack Obama’s winning of the Nobel Peace prize should encourage him to commit to an international treaty on global warming, the UN climate chief said Friday. As two weeks of UN climate talks concluded in Bangkok, there were fears of time running out for 192 countries to reach an agreement ahead of a December showdown in Copenhagen, the deadline for a deal to tackle global warming. The UN’s top climate official, Yvo De Boer, said he hoped Obama’s win would be “an …