The general public is under the impression that the world temperature record for the last century is accurate. That assumption is without merit.
A closely guarded secret of the climate gurus is that the temperature record of the Southern Hemisphere is unreliable and basically useless. This assertion was made by none other than James Hansen, global warming doyen, in a 1981 Science article. His pessimism was acknowledged by Phil Jones, another bigwig alarmist, in the 2009 Climategate emails where he suggested that most of the Southern Hemisphere data was made up.
Since the Southern Hemisphere data is worthless, we cannot have a valid global temperature record. We are left with only the Northern Hemisphere data. The raw rural data, unaffected by urban heat island anomalies, on similar latitude to latitude basis, suggests that the temperatures of today are the same as those of 75 years ago. The data for all Northern Hemisphere countries ranging from Greenland to southern Europe show no warming from 1940 to mid-1970, a period of noticeable cooling. (Remember the first Earth Day warned of catastrophic global cooling.) The warming from the mid-1970s to today is comparable to the warming experienced in the 1930s and 1940s.