"The Bureau of Meteorology (BoM) initially claimed the adjustments were part of its quality control procedures. But bureau chief executive Andrew Johnson later told Environment Minister Josh Frydenberg that investigations had found a number of cold-weather stations were not “fit for purpose” and would be replaced."
Aussie temperature tampering scandal: “Smart cards” filter out coldest temperatures. Full audit needed ASAP! - 'The story changes: first it was quality control, then equipment failure, now a smart card?'