The globally averaged combined land and ocean surface temperature data as calculated by a linear trend, show a
warming of 0.85 [0.65 to 1.06] °C3
, over the period 1880 to 2012, when multiple independently produced datasets exist.
The total increase between the average of the 1850–1900 period and the 2003–2012 period is 0.78 [0.72 to 0.85] °C,
based on the single longest dataset available 4
(see Figure SPM.1). {2.4}