Data Centers: Met Office UK, Met Agency Japan, NOAA and NASA/GISS both USA.
The figure shows the combined decadal temperature averages of the four data centers over the period 1880 to 2013. A simulation of the data between 1880-1979 by the NASA/GISS group is shown with the small red triangles. The results of this simulation were then used to make predictions on future temperature behaviour - red curves (1981) and blue triangles (1988). The prediction in red for the decade 2010-2019 is taken from a 2007 publication.
Conclusion: The increase in temperature as predicted by model calculations incorporating the measured increase of the greenhouse gasses in the atmosphere since 1880 is evident. The measurements are clearly in disagreement with the predicted natural variation hypothesis without that inclusion (gray area).
Clicking on the references in the figure leads to the abstract and/or original paper. The text "Combined Decadal Averages", the data points themselves and the references to the "Data Centers" can be clicked and leads to some details of the calculation of the averages and the underlying yearly temperature measurements. The average of the first three years of the present decennium is also shown. For a pdf-file of the figure click here.