World Meteorological Organization recently released a document with the above title. You can nab it here if you wanna.

Among many interesting graphs, this one is pretty much the one to be most impressed by.

Figure 1. Decadal global combined surface-air temperature over land and sea-surface temperature (°C) obtained from the average over the three independent datasets maintained by the UK Met Office Hadley Centre and the Climatic Research Unit, University of East Anglia, in the United Kingdom (HadCRU), NOAA-National Climatic Data Center (NCDC) and the US National Aeronautics and Space Administration-Goddard Institute for Space Studies (NASA-GISS). The horizontal grey line indicates the long-term average value for 1961–1990 (14°C).

That's our work, right there. A round of applause is in order.