Some people are still believing that the global temperature somehow has not increased, or increased less than expected in the last 18 years. Nothing is further from the truth: taking the average of the four most commonly used surface temperature series (GISS, NCEI, Hadcrut, JMA) until mid 2015 we get the following picture:
Yes, the last 18 years the linear increase was less than the increase in the 30 years before, but that does not mean the overall rise in global temperature anomaly was smaller: there is also this jump that needs to be taken into account. If we do that, the total increase is very consistently 0.14 degrees per decade since 1967.
Let’s zoom in on the upper right corner, it contains an extra message:
The median of all anomalies since mid 1997 lays .16 above the chosen reference temperature (the average of 1986 – 2006), but what is astonishing is thathalf of the months in the last 18 years have been warmer than any month before (with two exeptions). .