FILE - In this Aug. 20, 2013 file photo, Syrian refugees cross into Iraq at the Peshkhabour border point in Dahuk, 260 miles (430 kilometers) northwest of Baghdad, Iraq. In an authoritative report due out Monday, March 31, 2014, a United Nations climate panel for the first time is connecting hotter global temperatures to hotter global tempers. Top scientists are saying that climate change will complicate and worsen existing global security problems, such as civil wars, strife between nations and refugees. (AP Photo/Hadi Mizban, File)