A Late Glacial and Holocene 18O paleoclimate record form the afro-alpine Wulf Lake, Bale Mountains, Ethiopia

The Bale Mountains in the Southeastern Ethiopian Highlands are one of the few mountain ranges of Africa that were glaciated during the last glacial maximum. As a result of glacial retreat, numerous depressions started to be filled with lacustrine sediments and thus represent excellent environmental and climate archives for this fragile afro-alpine ecosystem. During a field campaign in 2017, a 4.8 m long sediment core was retrieved from the shorelines of Wulf Lake on the Sanetti Plateau at more than 4000 m altitude. Twelve radiocarbon data allow establishing a robust Late Glacial and Holocene chronostratigraphy covering the last 17,000 years. Apart from classical sedimentological parameters, we investigated and established a δ¹⁸O_sugar biomarker record. As demonstrated in previous studies, an unambiguous aquatic source identification is possible especially for the sugar biomarker fucose in our study area and allows reconstructing lake evaporation histories. We will compare our Late Glacial and Holocene δ¹⁸O_sugar record from Wulf Lake with the Holocene δ¹⁸O_sugar record from Garba Guracha (Bittner et al., 2022), as well as with other paleoclimate records, in order to contribute to the regional and over-regional paleoclimate reconstruction of Eastern Africa.

Reference:

Bittner et al., 2022. The Holocene lake-evaporation history of the afro-alpine Lake Garba Guracha in the Bale Mountains, Ethiopia, based on δ¹⁸O records of sugar biomarker and diatoms. Quaternary Research 105, 23-36.