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Subglacial carbonate deposits have been exposed on the lee sides of small protuberances on a bare polished and striated limestone bedrock surface in the immediate vicinity of the disappearing small glaciers in the south-eastern Alps (N Slovenia and NE Italy). The uranium-thorium dating of these carbonates indicates that they were deposited during the Last Glacial Maximum (LGM) and Younger Dryas (YD). The small glaciers in the Slovenian Alps (i.e., the Triglav and Skuta glaciers) are generally considered relicts of the Little Ice Age that were not continuously present due to the warm Holocene Climatic Optimum (HCO). If these glaciers had completely melted during the HCO, the the subglacial carbonates of the LGM and YD would have been exposed to frost weathering and would have had little chance of being preserved to the present day. While it has been postulated that subglacial carbonates are not very resistant to such weathering, no direct data have been available to date. Therefore, the objective of our study was to determine the rate of freeze-thaw weathering of subglacial carbonate deposits. Freeze-thaw analysis was performed in a controlled freeze-thaw chamber under dry and wet conditions. Preliminary results after 56 freeze-thaw cycles indicate an average mass loss of 2.13%. According to the high-altitude meteorological station adjacent to the Triglav Glacier, there is an average of 19 freeze and thaw cycles per year when there is no snow cover, indicating an average mass loss of 0.73% per year and a total mass loss in about 2000 years. These laboratory results suggest that the subglacial carbonates would likely have weathered in the absence of glaciers during the HCO and thus can be considered indicative of the recently exposed ice- or glacier-free surface for the first time since their deposition.

The accuracy and uncertainty of paleoclimate interpretations of geochemical and isotopic proxies from stalagmites depend critically on how accurately isotopic signals are transmitted through the vadose zone of the aquifer and how the elemental composition of the groundwater feeding the stalagmite changes as it passes through the aquifer.Results of the first year (2021) of drip-water monitoring at 15 drip sites in the Jama v Dovčku Cave in SE Slovenia are presented. Cumulative monthly samples were analysed for δ18O of water, δ13C of dissolved inorganic carbon (DIC), elemental composition of drip-water and concentration and δ13C of CO2 in the cave atmosphere. While the seasonal variability of δ18O of precipitation in 2021 at the nearest meteorological station exceeded 10 ‰ (from –15.42 ‰ in January to –5.28 in June), the intra-annual variability of δ18O of drip-water was reduced to 0.18–1.28 ‰ and showed no correlation with the thickness of the roof, which varied between >1 and 49 m. A discernible annual cyclicity was observed at some drip sites, with the highest δ18O values determined in winter and the lowest in late summer. Dissolved inorganic carbon (DIC) δ13C values exhibited a wide range (between –15.5 and –5.0 ‰), and drip sites could be divided into two groups: some drip sites exhibited large seasonal variability (up to 9.9 %) with low values in the warmer season, while the others varied within 2 concentration in the cave atmosphere was significantly higher from May to October, about 4000 to 8000 ppm, while it fluctuated between 700 and 1500 ppm in the colder part of the year. The δ13C values of CO2 varied between –23.8 and –15.2 ‰ and decreased exponentially with CO2 concentration. Similar to CO2, the δ13C values of DIC also decreased exponentially with increasing DIC concentration. The δ13C value of “added” CO2 in the atmosphere obtained from the δ13C x (C/C0-1) vs. (C/C0-1) plot (Sayles &% Curry, 1988) was –23.4 ± 2.6 ‰, which is almost identical to the CO2 added to the drip-water estimated from DIC concentration and δ13C values of DIC (–23.9 ± 3.4 ‰, considering the isotopic fractionation factor between CO2(g) and HCO3- from Mook et al. 1974). Chemical analysis showed that drip sites with a large seasonality of δ13C values have significantly lower saturation indices with respect to calcite in the warmer part of the year and that earlier calcite precipitation is most likely to occur at drip sites with lower drip rates. Reference:Mook et al., 1974, Earth Planet. Sci. Lett. 22,169–186.Sayles & Curry, 1988, Geochim. Cosmochim. Acta 52, 2963–2978. ACKNOWLEDGEMENT: We acknowledge the financial support of Slovenian Research Agency (J1-2478).

The retreat of ice shelves and glaciers over the last century provides unequivocal evidence of recent global warming. Glacierets (miniature glaciers) are an important component that highlights the global retreat of glaciers, but knowledge of their behaviour prior to the Little Ice Age is lacking. Here, we present subglacial carbonate deposits from a recently exposed surface previously occupied by the disappearing Triglav Glacier (southeastern European Alps) that may elucidate the glacier’s existence throughout the entire Holocene since their maximum uranium-thorium (U-Th) ages suggest their possible preservation since the Last Glacial Maximum and Younger Dryas. These thin deposits, formed by regelation, are easily eroded if exposed during previous Holocene climatic optima. The age data indicate the glacier’s present unprecedented level of retreat since the Last Glacial Maximum, and the potential of subglacial carbonates as additional proxies to highlight the extraordinary nature of the current global climatic changes.

Present is the role of formal education on natural disasters in Europe. To ensure a uniform overview, the study used secondary-school geography textbooks from the collection of textbooks at the Georg Eckert Institute for International Textbook Research in Braunschweig, Germany. Altogether, more than 160 textbooks from 36 European countries were examined in order to investigate how much their content (pages, text, figures) is related to natural-disasters topics, and to find out which types of hazards are presented more often. In the research it was also analyzed which disaster events are frequently used as an example.