FILE - In this Sept. 10, 2008 file photo girls hold hands to keep their balance as they walk the rails of flooded train tracks in Thiaroye Sur Mer, on the outskirts of Dakar, Senegal We

 

              FILE - In this Sept. 10, 2008 file photo girls hold hands to keep their balance as they walk the rails of flooded train tracks in Thiaroye Sur Mer, on the outskirts of Dakar, Senegal We
FILE - In this Sept. 10, 2008 file photo girls hold hands to keep their balance as they walk the rails of flooded train tracks in Thiaroye Sur Mer, on the outskirts of Dakar, Senegal Wednesday, Sept. 10, 2008. U.N. climate experts say global warming accelerated since the 1970s, breaking more countries’ temperature records than ever before. The World Meteorological Organization’s analysis Wednesday, July 3, 2013 calls the first decade of the new millennium an unprecedented era of climate extremes ranging from heat waves in Europe and Russia, to droughts in the Amazon Basin, Australia and East Africa, to huge storms like Tropical Cyclone Nargis and Hurricane Katrina.(AP Photo/Rebecca Blackwell, File)