VERIFICATION OF AUSTRALIAN MONTHLY DISTRICT RAINFALL TOTALS USING HIGH-RESOLUTION GRIDDED ANALYSES

The use of district rainfall totals for the description of Australian rainfall on monthly and longer time-scales has been investigated using a gridded rainfall dataset generated using an objective analysis tech nique. It has been verified that the operational district totals, gene rated within the Bureau of Meteorology for rainfall monitoring and pre diction purposes, provide a reasonable indication of rainfall on the w hole, both in the mean and in individual months. Some deficiencies hav e been found in the district totals in certain parts of the country, m ost notably in the subtropical parts of Western Australia, southern ha lf of the Northern Territory, tropical Queensland, and western Tasmani a, In each of these areas districts encompass geographical regions wit h large spatial variation in rainfall, and the distribution of station s available for the calculation of district average rainfall is not su fficient. The appropriateness of the district boundaries and the varia bility of rainfall within districts is also investigated.