About decadal and multi-decadal rainfall maps

How were the maps created?

Decadal and multi-decadal rainfall data is recorded at a network of stations across Australia. The data from these weather stations are stored electronically in the Bureau of Meteorology's database called ADAM (Australian Data Archive for Meteorology).

The 10, 20 and 30-year average rainfall maps are based on daily rainfall data from between 4000 and 7000 weather stations.The daily data were extracted from ADAM and a number of quality control checks were then applied to the data. For example, the data were checked for missing values over the length of the data record.

After the quality checks were applied to the data, monthly totals were calculated for each of the weather stations. An objective analysis technique was then applied to these station averages to produce regular gridded datasets covering Australia. These gridded datasets were analysed to obtain annual averages over each specified period.

Finally, the gridded data were visualised in a geographic information system and the colour maps created through this process.

You can find out more about the format of the gridded datasets and the analysis technique is described in the metadata.

Stations used in the analysis

Daily rainfall data from between 4000 and 7000 weather stations across Australia were used to create the decadal & multi-decadal rainfall maps. These stations are shown in the maps below.

Controls

Station maps

1910 1920 1930 1940 1950 1960 1970 1980 1990 2000

Rainfall metadata

The following metadata summary, and detailed metadata file, provide information on the decadal and multi-decadal rainfall grids. For example, information is provided about the format, spatial extents and analysis techniques used to generate the grids.

The detailed metadata file provides more information about these rainfall gridded datasets, including information about the analysis technique. You can also find out about the other gridded datasets we have available.

Copyright & contact information

Please note that the copyright for any data supplied by the Bureau of Meteorology is held in the Commonwealth of Australia and the purchaser shall give acknowledgement of the source in reference to the data. Apart from dealings under the Copyright Act 1968, the purchaser shall not reproduce (electronically or otherwise), modify or supply (by sale or otherwise) these data without written permission from the supplier.

If you want to know more, please contact us at webclim@bom.gov.au