Abrupt surface drying and fire weather Part 2: a preliminary synoptic climatology in the forested areas of southern Australia

Dramatic lowering of the humidity at the surface was observed at Canberra Airport and at Port Lincoln Airport AWS respectively during two recent Australian extreme fire weather events, that of the Canberra fires of 18 January 2003, and that of the lower Eyre Peninsula fires of 11 January 2005. These events have been described in more detail in Mills (2005a) and in a companion paper (Mills 2008), and the latter event also in Bureau of Meteorology (2005). As these two events led to the loss of several lives and massive property and infrastructure damage, and because fire activity increases very rapidly as fuel moistures reach extremely low values (Luke and McArthur 1978, p.88), further investigation of the meteorological factors that lead to such surface drying events is warranted. In Mills (2008) it was proposed that the abrupt surface dryings observed at Canberra and Port Lincoln were due to, first, deep upper to mid-tropospheric subsidAbrupt surface drying and fire weather Part 2: a preliminary synoptic climatology in the forested areas of southern Australia