Coarsely crystalline cryogenic cave carbonate – a new archive to estimate the Last Glacial minimum permafrost depth in Central Europe

Researchers have identified coarsely crystalline cryogenic cave carbonate (CCC) as a novel paleoclimate proxy, revealing that permafrost during the Last Glacial period penetrated to depths of at least 65 meters in Central European lowlands and uplands, with an isolated finding suggesting depths of up to 285 meters in the High Tatra mountains. This discovery contrasts with typical speleothem formation, which ceased during glacial periods, while CCC precipitation was restricted to them. By analyzing stable isotope values, U-series ages, and depth data from 20 caves across Germany, the Czech Republic, Slovakia, and Poland, the study estimates permafrost depths and demonstrates that permafrost thawing phases occurred repeatedly during marine isotope stages 4, 3, and 2, with significant CCC formation between 40–21 ka BP and 17–12 ka BP. This provides critical insights into the extent and variability of permafrost in glacier-free regions.

Žák, K., Richter, D. K., Filippi, M., Živor, R., Deininger, M., Mangini, A., & Scholz, D. (2012). Coarsely crystalline cryogenic cave carbonate – a new archive to estimate the Last Glacial minimum permafrost depth in Central Europe. Climate of the Past, 8(6), 1821–1837. https://doi.org/10.5194/cp-8-1821-2012