U.N. Secretary General Ban Ki-moon speaks during a conference on climate change in Abu Dhabi May 4, 2014. Ban said on Sunday he was hopeful that a goal of limiting global temperature rises to a ... more 
U.N. Secretary General Ban Ki-moon speaks during a conference on climate change in Abu Dhabi May 4, 2014. Ban said on Sunday he was hopeful that a goal of limiting global temperature rises to a maximum 2 degrees Celsius could be achieved, but urged governments to take practical action before it was too late. REUTERS/Stringer (UNITED ARAB EMIRATES - Tags: ENVIRONMENT POLITICS) less 
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Reuters | Photo By STRINGER / REUTERS
Sun, May 4, 2014 8:59 AM EDT