Individual weather station data from the Australian Bureau of Meteorology (BoM) was relied on to construct the AACI with the aim of ensuring the data:
- had history going back to 1981, which is the start of the reference period; and
- was measured consistently over time (or had been homogenised by BoM as discussed below).
The weather station data from the BoM was reviewed for reasonableness, detailed analysis was not undertaken. Therefore, reliance was placed upon this source to provide accurate and complete data information.
More specifically:
- The temperature measures are based on the 112 ACORN-SAT stations. This data has been homogenised by the BoM to ensure consistency over time.
- The rainfall data is based on all weather stations across Australia that collect rainfall data (around 2,000 stations).
- The wind data is based on 38 stations that are thought to provide the most reliable wind data, noting that wind measurement is inherently more uncertain.
- The sea level data is based on 16 tide gauges around the country and are taken from the BoM’s Baseline Sea Level Monitoring Project.
About the Bureau of Meteorology (BoM)
The BoM has been collecting weather data from all around Australia since its inception in 1906. Some discontinuities and inconsistencies occur due to changes in technology, instruments, location, or environment. However, for certain stations and time series, the BoM has put considerable effort and resources into homogenising the data to ensure consistency through time. This process is widely acknowledged to be state-of-the-art and has been implemented for a subset of the station data. The ACORN-SAT data covers 112 stations across Australia for temperature. The locations of these stations give relatively good coverage across the regions used in the AACI.
For more information on the data and the development of the AACI see Design Documentation.