Dust climatology of Mildura, Victoria, Australia: transport direction

Large‐scale geomorphic drivers that operate at continental scale are often climate driven. Changes in land use can accelerate wind erosion. The range of land management practises within one land use can have dramatic effect on ground cover and wind erosion. This study uses meteorological observations, land use, land management and dust concentration measurements of 129 dust events recorded between 1990 and 2007 to describe a dust chronology of Mildura, in south‐eastern Australia. Frontal and frontal trough weather systems account for 74% of dust events. Furthermore, 88% of dust events come from rangelands in the northwest and the cropping lands to the southwest. The cropping areas to the southwest are the most common source of dust, accounting for 66% of events There is no relationship between rainfall and dust activity in this study, suggesting that land‐management practices, especially on cropping lands, over‐ride the controlling effect of rainfall. When cropping lands received above average rainfall in spring and summer during the 1990s, cultivation for weed control lead to rapid decline in ground cover that predisposed the land to wind erosion in following summer and autumn. In drought years, dust blows into Mildura from all directions suggesting that dust is climate driven rather than controlled by land use. © 2019 John Wiley & Sons, Ltd. Long term dust measurements can provide an insight into the drivers of wind erosion. We examined the meteorological and land use drivers of 129 dust events collected over a 17 year period. Our analysis identified dust activity every year, dominated by cold front induced winds and variable dust source regions. In drought years, dust is also sourced from rangelands, but land management practices on cropping lands over‐ride the controlling effect of rainfall. Even above average rainfall was seen to lead to cultivation induced dust emission.