The destruction of the framework of “Notre-Dame de Paris” cathedral in the fire of April 15th 2019 is a unique and exceptional opportunity to investigate the woods that composed it. Indeed, the timber constituting part of the framework grew during the 12th-13th centuries, a period marked by a global warming, the MWP (∼900 -1350 AD). The objective of this project is to initiate a climate reconstruction of MWP with a high temporal resolution by studying the δ13C isotopic composition at the scale of individual charred oak ring from Notre-Dame de Paris. To this end, the project is composed of two parts. The first part will aim to understand how the heterogeneity of carbonization impacts the initial chemical properties of wood, in particular its δ13C isotopic composition. Oak wood will then be charred experimentally at different temperatures. Combination of Raman spectroscopy, infrared spectroscopy and gas chromatography coupled with an isotope ratio mass spectrometer (GC-irMS) will be used to determine the effect of temperature on the chemical and δ13C isotopic compositions of wood. Finally, in the second part, the aim will be to apply previous key insights on charred woods from Notre-Dame (following the availability of samples, the candidates would be able to work on archaeological samples from the same temporal window) to provide an annual-scale resolution climate reconstruction detailing in particular the frequency of extreme events during the MWP.
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