This post refers to my analysis of recorded annual rainfall trends at 13 stations located throughout Australia. The stations were all with long records (all over 100 years). The analysis used raw data (as recorded, without any adjustments) as published by the Australian Bureau of Meteorology (BOM). The 5-year moving mean annual rainfalls (in red) were added to the plots.
Plots are shown below for the 13 stations. At one station (Alice Springs) separate plots are made for two stations located 12 km apart: Alice Springs Post Office (1873-1987) and Alice Springs Airport (1941-2017).
Cape Leeuwin 1897-2017
Marble Bar 1895-2017
Victoria River Downs 1886-2017
Alice Springs Post Office 1874-1986
Alice Springs Airport 1942-2017
Moruya Heads 1876-2017
The long-term trend in the annual rainfall at most (9/13) of the stations show very little variability over the past century and more. There are very few cases of several consecutive years with rainfalls significantly lower or higher than the long-term average. Marble Bar (1995-2000) is such an example, although there are other examples.
Cape Leeuwin has experienced “abnormally” lower rainfalls, about 20% lower, since about 2000. This confirms widespread media reports of a regional drought in south-western Western Australia over that period.
Marble Bar experienced a wetter period, about 80% higher, during the 6-year period 1995-2000.
Victoria River Downs rainfall has been about 30% higher since about 1970.
Moruya Heads rainfall during the period 1950-1992 was about 25% higher than for other periods.
Please let me know what you think of my analyses. firstname.lastname@example.org
This article was written by Brian Gunter of Narooma, NSW, Australia. In his previous life Brian was an engineering hydrologist involved over many years in the analysis of rainfall and river flow data for the planning of water resources projects in Australia, Asia and Africa. In recent years he has been one of the Marine Rescue NSW (previously Royal Volunteer Coastal Patrol) volunteer weather observers who operate the Narooma station for the Bureau of Meteor