UN Framework Convention on Climate Change (UNFCCC) Executive Secretary Christiana Figueres, United Nations Secretary General Ban Ki-moon, Polish Prime Minister Donald Tusk and Marcin Korolec, President of COP19/CMP9, Polish Minister of Environment (1st L to 4th L) attend, along with other participants, the opening session of high-level segment of 2013 UN Climate Change Conference in Warsaw, Poland, on Nov. 19, 2013.(Xinhua/Zhang Fan)