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We cordially invite you to read the report on the implementation of the National Science Centre grant entitled "Mid-Eemian Climatic Oscillations...", which has been published in the latest issue of Wiadomości Uniwersyteckie (University News) (March 2024). We encourage you to delve into the reading.
Pidek I.A., Mroczek P., Żarski M., Jawiarczyk J., 2024. Reconstruction of climatic oscillations from 128,000 years ago as a result of interdisciplinary scientific cooperation. University News, UMCS Lublin, 74-75.
Link to University News (*.pdf, in Polish)
Grant page "Mid-Eemian Climatic Oscillations…" (in Polish)
In 2016, Dr. Marcin Żarski, a geologist from the Polish Geological Institute - PIB in Warsaw, during field mapping as part of the Detailed Geological Map of Poland (scale 1:50,000, Garwolin sheet), discovered over 20 fossil lake basins on the Garwolin Plain, which are fragments of an ancient lake district dated to at least 128,000 years ago. This discovery initiated detailed studies requiring significant financial resources. Lake sediments and peats are invaluable archives of the past, containing information about the history of vegetation, climate changes, and environmental shifts during Pleistocene interglacial warmings and in the Holocene, the current warm period. In 2019, an interdisciplinary research team secured a grant from the National Science Centre for the OPUS 14 project "Mid-Eemian climate oscillations. Reconstruction based on multidisciplinary studies of fossil lake sediments of the Garwolin Plain (Central Poland)". This project, coordinated by the Institute of Earth and Environmental Sciences at UMCS, brings together researchers from various Polish universities, PIG-PIB in Warsaw, the W. Szafer Institute of Botany of the Polish Academy of Sciences in Krakow, Tallinn University of Technology (Estonia), Leibniz Laboratory for Age Determination and Isotope Research (Germany), and Tanta University (Egypt). Reconstructions of the Eemian interglacial climate, dated to approximately 115-128,000 years ago, require the collaboration of geologists, geomorphologists, sedimentologists, palaeobotanists, palaeozoologists, and climate reconstruction specialists, who rely on modern pollen analogues.
The main method for studying biogenic sediments is the analysis of pollen and plant spores counted in several-centimeter-thick core layers extracted from fossil lakes (palynological method). It is a fundamental tool in the set of paleoecological methods. Hundreds of small sediment samples with a volume of 1 cm3 contain a rich spectrum of microscopic pollen grains with characteristic surface sculptures, which usually allow for identification to the species, or at least to the genus level, using a microscope with a magnification of 400-600x. Supplementary analyses include sedimentological studies, stable carbon and oxygen isotopes, macroscopic plant remains, and fossil cladocerans and diatoms, allowing for the reconstruction of conditions in the lakes and the evolution of the basins. Over 1100 modern palynological analogues from Europe and Asia, recorded in the European Pollen Database with detailed climatic parameters, are used for climate condition reconstructions.
So far, the best understood are short-term climate oscillations in the Holocene, which also have counterparts in older warmings. Research has shown that cooling and drying at the end of the thermal optimum of the Eemian interglacial, termed the "hazel phase," were particularly noticeable. This period saw a drop in water levels, leading to the disappearance of some lakes. The mid-Eemian climate oscillation was not recorded in two studied basins, whose geological and geomorphological situation favored constant groundwater supply. A complete record of the hazel phase was refined from the analyzed basins and compared with data from a renowned Eemian site in northern Germany. Based on annually laminated sediments from Bispingen, studied by Stefan Lauterbach and his team, published in 2024, it was determined that the hazel phase lasted 7130 years.
Research on past warm periods helps identify episodes of climate fluctuations related to natural variability, and in the context of the Eemian interglacial, can contribute to a deeper understanding of contemporary climate changes.
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