Palaeo-coastal and vegetation response to warming a high Arctic – using the Paleogene – Eocene in Svalbard, Arctic Norway as a laboratory for future change
Authors: Jensen Maria Ansine , Jelby Mads , Jochmann Malte , Marshall Chris 
Published: February 2023

The polar regions are particularly sensitive to modern climate change. Despite the Arctic being home to isolated societies and vulnerable ecosystems, little is known about landscape and ecosystem response to climate change beyond short historical records. The Paleogene - Eocene near-shore to continental record from the Central Tertary Basin (CTB) of the Svalbard archipelago provides a unique laboratory in which to study surface response to temperature and precipitation change during hyperthermals. At the time Svalbard was located in the high Arctic at c.75 degrees north and had a polar night and no night during summers. This time interval was a period of high atmospheric CO2 levels and a warm greenhouse climate and the best existing analogue for projected near future warming.C-isotopes has been obtained from across the PETM (Cui et al., 2011; 2021), and glendonites (Spielhagen & Tripati 2009) and leaf morphologies (Clifton 2012) has provided evidence of cold- and warm spells after the PETM. Ongoing work by the authors and collaborators have shown the possibility to obtain high resolution paleoclimate records (precipitation, atmospheric dust/wind, forest fires) from coal seams, increasing the resolution of palaeoclimate records from the continental part of the succession significantly.&#160;Exploration drilling and research activity for decades in the CTB has yielded an extensive amount of lithological, geochemical and biostratigraphical data. More than 500 sedimentological drill cores through the lower part of the Paleogene sedimentary record in Svalbard which provides a unique possibility to construct the palaeo terrain surface. This creates a 3D palaeoclimate laboratory that to our knowledge has no counterparts in the Arctic and rarely onshore in general. Age constraints exists from bentonite ash layers preserved in coal seams (Jones et al. 2017) and orbitally tuned isotope records (Charles et al 2011). &#160;We use the possibilities for combination of a high-resolution 3D reconstruction of physical and vegetation elements of a coastal landscape with high-resolution proxies for vegetation cover, temperature, precipitation, atmospheric dust and forest fires to investigate response and feedback mechanisms in a warm Arctic.&#160;ReferencesCharles, A.J. et. al.2011. "Constraints on the numerical age of the Paleocene&#8208;Eocene boundary." Geochemistry, Geophysics, Geosystems 12, no. 6.Clifton, A.J., 2012. The Eocene flora of Svalbard and its climatic significance (Doctoral dissertation, University of Leeds).Cui, Y. et al. 2011. "Slow release of fossil carbon during the Palaeocene&#8211;Eocene Thermal Maximum." Nature Geoscience 4, no. 7 (2011): 481-485.Cui, Y. et al. 2021. "Synchronous Marine and Terrestrial Carbon Cycle Perturbation in the High Arctic During the PETM." Paleoceanography and Paleoclimatology 36, no. 4 (2021): e2020PA003942.al and geochemical signals." Palaeogeography, Palaeoclimatology, Palaeoecology 302, no. 3-4: 156-169.Spielhagen, R., & Tripati, A.. "Evidence from Svalbard for near-freezing temperatures and climate oscillations in the Arctic during the Paleocene and Eocene." Palaeogeography, Palaeoclimatology, Palaeoecology 278, no. 1-4 (2009): 48-56.Jones, M. Et al., 2017. "Constraining shifts in North Atlantic plate motions during the Palaeocene by U-Pb dating of Svalbard tephra layers." Scientific reports 7, no. 1: 1-9.