Late Quaternary climate change in the north-eastern highlands of Ethiopia: A high resolution 15,600 year diatom and pigment record from Lake Hayk

TY - JOUR

T1 - Late Quaternary climate change in the north-eastern highlands of Ethiopia: A high resolution 15,600 year diatom and pigment record from Lake Hayk

AU - Loakes, K.L.

AU - Ryves, D.B.

AU - Lamb, H.F.

AU - Schäbitz, F.

AU - Dee, M.

AU - Tyler, J.J.

AU - Mills, K.

AU - McGowan, S.

N1 - CODEN: QSRED Funding details: Natural Environment Research Council, NERC Funding details: Loughborough University, Lboro Funding details: Queen's University Belfast, QUB Funding details: University College Cork, UCC, 806 Funding details: British Geological Survey, BGS Funding details: Universität zu Köln, UoC Funding text 1: With thanks to the the University of Cologne CRC (Collaborative Research Centre) 806 for funding core collection: http://www.sfb806.uni-koeln.de/index.php/projects/former-projects/a3. Thanks to Oliver Langkamp (student co-worker at Cologne University) for his help preparing and performing the coring. Three AMS 14C dates were awarded to Katie Loakes under the the QRA-14CHRONO Centre Radiocarbon Dating award, supported by supported by Prof Paula Reimer (14CHRONO centre, Queens University Belfast). Katie Loakes was supported by a Loughborough University PhD award. Keely Mills publishes with the approval of the Executive Director, British Geological Survey (NERC). We thank both reviewers for their thoughtful and constructive comments which have helped improve the manuscript. Funding text 2: With thanks to the the University of Cologne CRC (Collaborative Research Centre) 806 for funding core collection: http://www.sfb806.uni-koeln.de/index.php/projects/former-projects/a3 . Thanks to Oliver Langkamp (student co-worker at Cologne University) for his help preparing and performing the coring. Three AMS 14C dates were awarded to Katie Loakes under the the QRA-14CHRONO Centre Radiocarbon Dating award, supported by supported by Prof Paula Reimer (14CHRONO centre, Queens University Belfast). Katie Loakes was supported by a Loughborough University PhD award. Keely Mills publishes with the approval of the Executive Director, British Geological Survey (NERC). We thank both reviewers for their thoughtful and constructive comments which have helped improve the manuscript.

PY - 2018

Y1 - 2018

N2 - Multi-proxy analyses of an 8 m sediment core from Lake Hayk, a closed, freshwater lake in the north-central highlands of Ethiopia, provide a record of changing lake level and inferred regional climatic change for the last 15.6 cal ka years. Between ca. 15.6–15.2 cal ka BP, a lowstand was synchronous with Heinrich Event 1 and an intense drought across Eastern Africa. At ca. 15.2 cal ka BP a lake began to develop at the core site in response to wetter conditions, at the onset of the African Humid Period (AHP). However, in contrast to other lakes in eastern Africa, Hayk lake level fell around ca. 14.8 cal ka BP, indicating a climate shift towards aridity. The lake began filling again at ca. 12.3 cal ka BP and reached maximum water depth between ca. 12.0–10.0 cal ka BP. Lake level declined slowly during the Holocene, culminating in the termination of the AHP at Hayk between ca. 5.2–4.6 cal ka BP. In the late Holocene, ca. 2.2–1.3 cal ka BP, Lake Hayk was again deep and fresh with some evidence of short-term lake level variability. The palaeo-record from Lake Hayk indicates that while it experienced, to a broad degree, the same glacial-interglacial dynamics and sub-millennial shifts in climate found in other palaeolimnological records from eastern Africa, there are offsets in timing and rate of response. These differences reflect chronological discrepancies between records, as well as the varying climate sensitivities and site-specific factors of individual lake basins. This record highlights the different responses by lakes in a climatically vulnerable area of Ethiopia.

AB - Multi-proxy analyses of an 8 m sediment core from Lake Hayk, a closed, freshwater lake in the north-central highlands of Ethiopia, provide a record of changing lake level and inferred regional climatic change for the last 15.6 cal ka years. Between ca. 15.6–15.2 cal ka BP, a lowstand was synchronous with Heinrich Event 1 and an intense drought across Eastern Africa. At ca. 15.2 cal ka BP a lake began to develop at the core site in response to wetter conditions, at the onset of the African Humid Period (AHP). However, in contrast to other lakes in eastern Africa, Hayk lake level fell around ca. 14.8 cal ka BP, indicating a climate shift towards aridity. The lake began filling again at ca. 12.3 cal ka BP and reached maximum water depth between ca. 12.0–10.0 cal ka BP. Lake level declined slowly during the Holocene, culminating in the termination of the AHP at Hayk between ca. 5.2–4.6 cal ka BP. In the late Holocene, ca. 2.2–1.3 cal ka BP, Lake Hayk was again deep and fresh with some evidence of short-term lake level variability. The palaeo-record from Lake Hayk indicates that while it experienced, to a broad degree, the same glacial-interglacial dynamics and sub-millennial shifts in climate found in other palaeolimnological records from eastern Africa, there are offsets in timing and rate of response. These differences reflect chronological discrepancies between records, as well as the varying climate sensitivities and site-specific factors of individual lake basins. This record highlights the different responses by lakes in a climatically vulnerable area of Ethiopia.

KW - African Humid Period

KW - Diatoms

KW - Ethiopia

KW - Heinrich event

KW - Holocene

KW - Lake level

KW - Palaeolimnology

KW - Pigments

U2 - 10.1016/j.quascirev.2018.09.005

DO - 10.1016/j.quascirev.2018.09.005

M3 - Article

SN - 0277-3791

VL - 202

SP - 166

EP - 181

JO - Quaternary Science Reviews

JF - Quaternary Science Reviews

ER -