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The idea that humans can ever know exactly what the temperature is or was, everywhere on Earth – including the vast oceans – all the time, is amusing but not much else.

Reification is the Fallacy of Misplaced Concreteness. It is a mental process by which someone comes to believe that an abstraction (idea or concept) is a material, physical object in the real world. Mike Hulme observes that many people are obsessing over global temperatures, not realizing they are abstractions and not things to be feared. He provides calm and sensible views regarding global temperature reporting. The post at his blog is Climatism and the Reification of Global Temperature. Excerpts in italics with my bolds.

Over the last 40 years global-mean surface air temperature – ‘global temperature’ for short – has gained an extraordinary role in the science, politics and public discourse of climate change. What was once a number crudely calculated through averaging together a few dozen reasonably well-spaced meteorological time series, has become reified as an objective entity that simultaneously measures Earth System behaviour, reveals the future, regulates…