In Search of Past Analogs to the Current Interglacial: MIS 11 Climate Record

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This grant supports the development of millennial-scale resolution records from Lake Baikal in continental Eurasia. These sediments are of age Marine Isotope Stage (MIS) 11, an interglacial period considered the closest analog to the elapsed portion of the Holocene and possibly to global climate of the future based on similar orbital configurations of the Earth now and then. Because of this similarity, understanding MIS 11 climate and being able to simulate climatic characteristics of MIS 11 using modern climatic models is essential to improve our ability to predict future climate.This project addresses the first challenge (to advance our understanding of MIS 11 climate in the Northern Hemisphere) by developing a new MIS 11 record using the archived sediments from Lake Baikal drill cores, representing arguably the best continuous multi-proxy records from continental Eurasia. The main focus will be detailed palynological (pollen) and diatom records, supplemented by organic carbon and nitrogen proxies from the latest drill core, which contains an almost 7-meter continuous section of the MIS 11 interval. This remarkably thick section, with a robust age model based on paleomagnetic event/reversal scale, orbital tuning and basin-wide diatom biostratigraphy, makes it perhaps the best MIS 11 archive in continental Eurasia. The project will explore three important aspects of the MIS 11 interglacial:1) Do the new detailed multi-proxy records support existing preliminary evidence for interglacial climate variability during MIS 11?2) Was MIS 11 (or any part of it) warmer and/or more humid than the Holocene?3) Does the climatic trend in continental Asia during the mid-Brunhes reinforce or weaken the MIS 11/Holocene analogy?The project will increase spatial coverage of MIS 11 in the Northern Hemisphere (continental MIS 11 records are sparse) and provide new data on warmth and stability of MIS 11 interglacial climate. The project will also test which of the direct MIS 11/Holocene analogies are reliable in the context of mid-Pleistocene climatic trend. In addition, results will provide new important implications for Pleistocene stratigraphy in Eurasia and for terrestrial productivity, carbon export and storage linked with changing vegetation/biome types. Work will be carried out in collaboration with institutions in Russia and Belarus.