Do you understand that the 'average' can be manipulated by where you put weather stations and how many in a given area as well, together with how many cold stations you close down.
For instance the BOM closed down Australia's coldest mainland weather station.
Just one example.
A bigger example is the paucity of data for the southern hemisphere with the South Pole in particular barely reported upon.....
You can be fed an illusion very easily as a result of this.