The latest report includes data that indicates the rate of warming from 1998 to 2012 slowed to about half the average rate since 1951, citing natural variability in the climate system, as well as cooling effects from volcanic eruptions and a downward phase in solar activity.
http://www.cbsnews.com/8301-205_162-57603772/controversy-over-u.n-report-on-climate-change-as-warming-appears-to-slow/
http://www.cbsnews.com/8301-205_162-57603772/controversy-over-u.n-report-on-climate-change-as-warming-appears-to-slow/