The Changing Nature of Australian Droughts

Abstract

Rainfall over nearly all of Australia during the cooler half of the year (May–October) was well below average in 2002. Mean maximum temperatures were very high during this period, as was evaporation. This would suggest that drought conditions (precipitation minus evaporation) were worse than in previous recent periods with similarly low rainfall (1982, 1994). Mean minimum temperatures were also much higher during the 2002 drought than in the 1982 and 1994 droughts. The relatively warm temperatures in 2002 were partly the result of a continued warming evident in Australia since the middle of the 20th century. The possibility that the enhanced greenhouse effect is increasing the severity of Australian droughts, by raising temperatures and hence increasing evaporation, even if the rainfall does not decrease, needs to be considered.