Activists demonstrate during a protest against the United Nations Climate Change Conference in Cancun, Mexico, Dec. 5, 2010. According to the UN weather agency, 2010 is "almost certain" to rank among the three hottest years on record, and the 2001-2010 decade is undoubtedly the warmest period since the beginning of weather records in 1850. [Xinhua]

 An activist demonstrates during a protest against the United Nations Climate Change Conference in Cancun, Mexico, Dec. 5, 2010. According to the UN weather agency, 2010 is "almost certain" to rank among the three hottest years on record, and the 2001-2010 decade is undoubtedly the warmest period since the beginning of weather records in 1850. [Xinhua]