The Bureau of Meteorology finds Australia is still getting colder a century later

Surprisingly, the World War I era temperatures are still changing. Mornings that seemed nippy at the time are now susceptible to frosts.

Someone should warn the farmers — except they’re all dead.

Thanks to Chris Gillham for independently and laboriously going through the new unannounced changes in another cycle of BOM’s hidden revamp of Australia’s history. ACORN 2.2 is the latest version of the Australian Climate Observation Reference Network of “the best” 112 weather stations across Australia.

Graham Lloyd, The Australian

“The bureau has now remodelled the national temperature ­dataset three times in just nine years,” Dr Jennifer Marohasy said.

In the last five years the ACORN re-revisions by the BOM have discovered another quarter of a degree of warming that we didn’t know about from the last hundred years. It’s not clear why the BOM doesn’t want to tell the world how good they are at correcting thermometer records from 1913. It seems like a remarkable skill.

The minima just keep getting cooler

Chris Gillham plots the longest running stations from the ACORN 2.2 set against the old raw readings:

Who knew all those old [...]