Dust Emissions from Kati Thanda-Lake Eyre: a Review

Kati Thanda-Lake Eyre (KT-LE) sits at the heart of Australia's dust transport system. Satellite mapping demonstrates that the lower Channel Country/northern KT-LE represents a global dust hotspot - the largest in the Southern Hemisphere. This dust is transported widely, with two dominant plume pathways; southeast, across the Tasman Sea, South Pacific Ocean and Southern Ocean, and northwest over the Pilbara/Kimberly and Indian Ocean. Marine sedimentary records imply KT-LE has been emitting dust throughout the Quaternary and potentially longer, although dust deposits linked directly to KT-LE exist only for the past similar to 55 kyr. The southern section of KT-LE emits little dust today; however, palaeo-aeolian sediments outcrop in, and mantle, the southern lake margins, pointing to the possibility of major net dust deflation episodes over the last glacial cycle. The spatial extent of net-deflation episodes remains uncertain. Only one event, at 30-15 ka, is evident in both lake sedimentary records and distal dust records. Over the late Pleistocene, it remains difficult to quantity the contribution of KT-LE sediment to Australia's dust load, although estimates suggest KT-LE generated 13% and 22% of Australia's dust load over the last 80 and 40 ka, respectively. Modern-day/Holocene dust emissions are periodic and appear coupled to arid-humid cycles, with sediment recharge a key contributing factor. During the late Pleistocene, controls on emissions are less clear, but likely coincided with large-scale changes in moisture. Despite 80 years of dust research at KT-LE, there remains much to learn about climate-landscape interactions and dust generation in Australia's arid heart.