Ross McKitrick made the same argument over a decade ago: Why Should We Trust A Statistic That Might Not Even Exist?
“Discussions on global warming often refer to ‘global temperature.’ Yet the concept is thermodynamically as well as mathematically an impossibility,” says Science Daily, paraphrasing Bjarne Andresen, a professor at the University of Copenhagen’s Niels Bohr Institute, one of three authors of a paper questioning the “validity of a ‘global temperature.’”
“The temperature obtained by collecting measurements of air temperatures at a large number of measuring stations around the globe, weighing them according to the area they represent, and then calculating the yearly average according to the usual method of adding all values and dividing by the number of points.”
But a “temperature can be defined only for a homogeneous system,” says Andresen. The climate is not regulated by a single temperature. Instead, “differences of temperatures drive the processes and create the storms, sea currents, thunder, etc. which make up the climate”.