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Research in Antarctica is of great importance for understanding the Earth's climate system and the processes that drive it. This study evaluated the spatial distribution of glacial sediment properties on the Bellingshausen Dome or Collins Ice Cap (King George Island, Antarctica). The particle-size distribution, pH H2O, total organic carbon (TOC), mobile forms of ammonium nitrogen (N–NH4), potassium (K2O), and phosphorus (P2O5) were measured and then spatially modelled using regression kriging (RK) and ordinary kriging (OK) approaches. The terrain attributes (elevation, aspect, slope) derived from a digital elevation model with 10-m spatial resolution and distance from a coast were used as explanatory variables. Multiple linear regression models were fitted to describe the relationships between the covariates and properties. The performance of the models was evaluated by the mean absolute error (MAE), root mean square error (RMSE), coefficient of determination (R2), and Nash–Sutcliffe efficiency coefficient (NSE) indices. Overall, model performance statistics showed that RK models performed better than OK and the spatial patterns of some properties were closely related to the character of the glacier topography. Thus, the application of the RK method in combination with auxiliary environmental covariates improved the accuracy of spatial prediction. [ABSTRACT FROM AUTHOR]

The surface of mountain glaciers is a place of accumulation of various biogenic organomineral and mineral compounds. As a result of intensive mass deglaciation of glaciers due to climate change and anthropogenic activity, this material can significantly affect the transformation of the landscape in the periglacial zone. Thus, this work considers the contamination of the surface of the Arctic, Antarctic, and Caucasian glaciers by priority pollutants. Atomic absorption spectroscopy was used to analyze trace elements (Cu, Zn, Ni, Cd, Pb) from cryoconite deposits. It was revealed that the cryoconite dust on the Ray-Iz glacier (Polar Urals) has a high level of nickel contamination, which comes to the glacier from local rock materials as a result of their weathering. The lowest concentrations of trace elements are found in one of the Arctic plots located at Mushketov and Aldegonda glaciers, the Caucasus, and the Antarctic, which is due to their relatively low content in the composition of rocks and the relatively low contribution of long-range transport of matter to the polar regions. Contamination of moraine sediments in the periglacial zone can make a significant contribution to the formation of the soil cover of these territories, the pollution of water bodies near the glacier, as well as affect the quality of life of the people living in the immediate vicinity of the mountain areas. [ABSTRACT FROM AUTHOR]

The paper discussed the influence of the forms of sediment accumulation on the surface of glaciers on their chemical and physicochemical properties. The materials sampled from the surface of five glaciers of the Svalbard Archipelago was analyzed. We studied such forms of sediment accumulation as dirt cones - the ice core covered with sediments and cryoconite holes - hollows on the glacier surface containing cryoconite material. Parameters such as total organic carbon content, microbiological activity, pH, the content of mobile forms of potassium and phosphorus, and concentrations of heavy and trace metals were studied. Also, mesomorphological studies were carried out and the polydisperse composition of the sediments was determined. According to the results of this work, it was found that the content of organic carbon in the material selected from dirt cones and cryoconite holes can be up to 2.5%, but the content of clay particles in it is mainly at the 10–15% level. Potassium concentrations are up to 250 mg/kg, and phosphorus is up to 800 mg/kg. The content of metals is typical or lower than in the previously published data. The main influence on the chemical composition of materials has a geographical factor of the sampling site, rather than the form of material accumulation. [ABSTRACT FROM AUTHOR]

Using the positive degree days approach and ERA-Interim reanalysis downscaled data, the researchers ran a melt model spatially gridded at 200 m with annual temporal resolution over 32 years and estimated surface melt (SM) and surface runoff (SR) on the Antarctic Peninsula. The model was calibrated and validated independently by field measurements. The maximum surface melt values occurred in 1985 (129 Gt), and the maximum runoff (40 Gt) occurred in 1993; both parameters showed minimum values in 2014 (26 Gt and 0.37 Gt, respectively). No significant trends are present. Two widespread positive anomalies occurred in 1993 and 2006. The results reveal that the floating ice areas produce an average of 68% of runoff and 61% of surface melt, emphasizing their importance to coastal hydrography. During the seven years preceding the Larsen B collapse, surface melt retention was higher than 95% on floating ice areas, and negative runoff anomalies persisted. Excluding the islands, the vicinity of this former ice shelf exhibits the highest specific surface melt and runoff across the studied area. [ABSTRACT FROM AUTHOR]

Glacier mass balance measurements, reconstructions and modeling are the precondition for assessing glacier sensitivity to regional climatic fluctuations. This paper presents new glaciological and geodetic mass balance data of Austre Grønfjordbreen located in the western part of Nordenskiöld Land in Central Spitsbergen. The average annual mass balance from 2014 to 2019 was −1.59 m w.e. The geodetic mass balance from 2008 to 2017 was −1.34 m w.e. The mass balance was also reconstructed by the temperature-index model from 2006 to 2020 and by spatially-distributed energy-balance models for 2011–2015 and 2019. We found a cumulative mass balance of −21.62 m w.e. over 2006–2020. The calculated mass-balance sensitivity to temperature was −1.04 m w.e. °C−1, which corresponds to the highest glacier mass balance sensitivity among Svalbard glaciers. Sensitivity to precipitation change was 0.10 m w.e. for a 10% increase in precipitation throughout the balance year. Comparing the results of the current study with other glacier mass balance assessments in Svalbard, we found that Austre Grønfjordbreen loses mass most rapidly due to its location, which is mostly influenced by the warm West Spitsbergen Current, small area and low elevation range. [ABSTRACT FROM AUTHOR]

Enormous deglaciation in the polar and mountainous regions of the Earth is associated not only with large-scale climatic changes but also with the global transfer of black carbon (BC) microparticles, which accumulate on the surface of glaciers and lead to changes in albedo and the rate of degradation of ice. BC is the product of an incomplete combustion of fossil fuels, volcanic eruptions, and wildfires. The accumulation of organogenic microparticles leads to the formation of cryoconites, which are dust made of a combination of small rock particles and the result of anthropogenic activities (fossil fuel combustion) that play a special role in deglaciation. Here, we describe the content of trace metals and nutrients in accumulation of the BC from glaciers of Fildes Peninsula, King George Island, Western Antarctica. The analysis of trace metals concentrations showed that most of the studied elements (Cr, Pb, Zn, Ni) have a volcanic origin; at the same time, Cd and Cu have been accumulated as a result of anthropogenic activity. The content of nutrients in BC are most similar with Technosols, which forms near the scientific station at King George Island. The particles of BC can be translocated into organisms, which could pose a significant risk for living organisms and humans. [ABSTRACT FROM AUTHOR]