Identification of dust transport pathways from Lake Eyre, Australia using Hysplit

Abstract

<p>The HYbrid Single-Particle Lagrangian Integrated Trajectory model (HYSPLIT_4) is used to create seasonal climatologies (1980–2000) of air parcel trajectories from the Southern Hemisphere's most active dust source Lake Eyre, Australia. Daily trajectories were computed forward for eight days from an origin centered over Lake Eyre at 500 m above the ground surface. Trajectory density maps were then created within a GIS for five levels; 0–500 m agl., 500–1000 m agl., 1000–1500 m agl., 1500–2000 m agl. and 2000–5000 m agl. These show that air parcel trajectories originating from Lake Eyre can affect regions many thousands of kilometers from the Australian continent in a relatively short period of time. Importantly, under favourable atmospheric conditions these air parcels have the potential to transport dust and other aerosols. During the austral winter, trajectories extended north to the southern Philippines highlighting the potential for dust from central Australia to affect most of Indonesia. This includes the tropical rainforests of Borneo and New Guinea, and the coral reefs of northern Australia and the Indonesian archipelago. We also show the potential for transport of dust from Lake Eyre to the Antarctic and much of the South Pacific and Southern Oceans. Accordingly, dust from Lake Eyre may affect biogeochemical cycles, sediment budgets, atmospheric processes and a wide range of ecosystems over a region much larger than previously thought. This highlights the need for further research to confirm the deposition of dust in the areas mapped by the present study.</p>