America and much of the world are baking in record temperatures. 170m Americas are under local heat alerts. The seawater in Florida is hitting 100 degrees or more. Hikers are dropping dead in Arizona, Greece is on fire, and July is set to be the hottest month in living memory. To some right-wingers, though, immersed in climate change denial and conspiracy theories, it isn't even happening. It's a hoax, and the numbers reported are false.
.Mr Oliver's claim that the BBC was using ground temperatures is false
The usual method is to find divergent readings from nearby weather stations and use the lower number to claim the higher number is fake. It depends on general ignorance of how shade, time of day, wind, elevation, proximity to urban centers or water and countless other factors may affect recorded temperature. In one example doing the rounds on social media, for example, the difference in temperature between the interior of Sicily (47C) and a weather station in sea-side Palermo (37C) is taken as proof the BBC is faking its data.