Summary: | Related paper: Zhou, Y., McManus, J., 2022. Extensive evidence for a last interglacial Laurentide outburst (LILO) event. Geology 50, 934. https://doi.org/10.1130/G49956.1 Abstract: A glacial lake outburst flood or accelerated ice sheet melting some 8,200 years ago (8.2 ka) caused the largest abrupt climate change event during the Holocene. It has been proposed that this 8.2-ka event has an analog during the Last Interglacial. Here, we characterize in detail the provenance, timing, and delivery mechanism of a layer of red sediments deposited across much of the Northwest Atlantic at 125-ka. Our observations provide strong support for the occurrence of a Last Interglacial Laurentide Outburst (LILO) event that was analogous to the 8.2-ka event in all three aspects, and likely surpassed it in magnitude. The freshwater discharge associated with the 125-ka LILO event may explain a series of abrupt global changes, including a reduction of the North Atlantic Deep Water and reinvigoration of the Antarctic Bottom Water. Our findings suggest that the mechanism that triggered the LILO event may be an integral part of the deglacial sequence of events, during which the final collapse of the contiguous Laurentide Ice Sheet (LIS) takes place 3.5 – 4 kyr after full interglacial temperature is reached in the middle and high northern latitudes.
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