This graph illustrates the change in global surface temperature relative to 1951-1980 average temperatures. The 10 warmest years in the 134-year record all have occurred since 1998, with 2010 and 2005 ranking as the warmest years on record (Source: NASA/GISS). This research is broadly consistent with similar constructions prepared by the Climatic Research Unit and the National Atmospheric and Oceanic Administration.
The time series below shows the five-year average variation of global surface temperatures from 1884 to 2013. Dark blue indicates areas cooler than average. Dark red indicates areas warmer than average.