Rainfall variability in eastern Australia over the last 130 kyr

• Applicant: Dr. Martina Hollstein
• Subject Area: Palaeontology ; Geology
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 554781931

Eastern Australia is recurrently affected by severe droughts and floods that have tremendous effects on the ecological and socioeconomic systems of Australia. The regional rainfall variability is coupled to the Australasian monsoon and the El Ninyo-Southern Oscillation. Today, the sea surface temperature (SST) and vigor of the Pacific western boundary currents, particularly the East Australian Current (EAC), additionally influence rainfall along the east Australian coast with a warmer and stronger EAC promoting rainfall. However, the role of ocean temperatures in regulating the climate in eastern Australia is poorly understood. For instance, climate projections suggest that eastern Australia will experience long-term drying during the 21st century despite a warmer EAC. Reconstructing past changes in rainfall over eastern Australia along with the SST and vigor of the western boundary currents is therefore critical to better understand their long-term connection. The aim of the proposed project is to reconstruct changes in east Australian rainfall and ist relation to SST over the last glacialinterglacial cycle. To this end, records of planktic foraminiferal Mg/Ca (SST proxy) and records of compound-specific isotopes in plant leaf waxes (rainfall proxy) will be generated from marine sediment cores retrieved along a latitudinal transect at the East Australian margin. The proposed reconstructions will also help to better assess the impact of future SST changes on Australian rainfall. The project is supposed to be conducted at MARUM - Center for Marine Environmental Sciences, University of Bremen.

• DFG Programme: Research Grants