A cycling between warm ocean surface waters and cool ocean surface waters in the Eastern Pacific called El Nino and La Nina, for centuries, has been a primary driver of relative atmospheric warmth and coolness. During the times when the Eastern Pacific disgorged its heat, the Earth’s atmosphere warmed. And during times when the same region cooled, a portion of atmospheric heat was taken back and transferred into the world’s oceans.
http://robinwestenra.blogspot.co.nz/2014/02/january-2014-3rd-hottest-on-record.html