Abstract

When investigating rainfall trends in the Murray Mallee and the Upper Eyre Peninsula regions, annual rainfall and winter, spring, and autumn rainfall have shown a significant decrease over the last 73 years, from 1950 to 2023, for the selected stations in the regions. However, summer rainfall in most of the region shows an increasing trend. In Kimba, Kyancutta and Cowell, summer rainfall is quite low compared to Brooker, Cleve, Cummins, Lock, Tumby Bay, Yallunda Flat and Yeelanna. From the selected stations in the Murray Mallee, most of the regions show a decreasing trend in the rainfall and few stations show an increasing trend in the annual rainfall. Callington, Murray Bridge, and Mannum regions show more than 500 mm of rain after the 1970s. Monarto Safari Park station had recent rainfall records only; however, it also shows an increasing rainfall trend. The vegetation made in the Monarto area in the 1970s seems to have been, by chance, a great enough area to enhance the rainfall in the surrounding regions in Murray Bridge and Callington. Each station data is analysed using trend analysis with exponential smoothing, and change-point analysis methods are used in annual seasonal rainfall and mean minimum temperature and for the mean maximum temperature in the Murray Mallee and Upper Eyre Peninsula regions. Also, based on the high-quality data available in some stations, long-term data from late 1880 was analysed to find any significant changes that have happened with the historical data. The important change points observed in maximum, minimum, and reduction in rainfall may influence fast-growing industrial activities that occur in land use patterns, which is caused by effective urbanisation damage to water sources. This study will continue investigating the relationship between land use and climate changes that may impact South Australian rainfall patterns.