Optical, Geochemical and Mineralogical Characteristics of Light-Absorbing Impurities Deposited on Djankuat Glacier in the Caucasus Mountains
| Autor: | Viktoria Krupskaya, Maria Shahgedanova, Sergey Goryachkin, Stanislav Kutuzov |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
Caucasus
light-absorbing impurities Geography Planning and Development Fluorescence spectrometry Mineralogy Aquatic Science Mineral dust spectral reflectance Biochemistry complex mixtures Cryoconite Organic matter TD201-500 Water Science and Technology chemistry.chemical_classification mineral dust geography geography.geographical_feature_category Water supply for domestic and industrial purposes Glacier Hydraulic engineering Albedo Snow chemistry Environmental science glaciers TC1-978 Ablation zone albedo |
| Zdroj: | Water Volume 13 Issue 21 Water, Vol 13, Iss 2993, p 2993 (2021) |
| ISSN: | 2073-4441 |
| DOI: | 10.3390/w13212993 |
| Popis: | Supra-glacial material, including light-absorbing impurities (LAI) such as mineral dust of crustal and soil origin, black carbon, algae and cryoconite, reduce the reflectance of snow and glacier ice. The reduction depends on the amount of LAI and their physical and chemical properties, which vary spatially and temporally. Spectral reflectance data and snow and ice samples, containing LAI, were collected in the ablation zone of the Djankuat Glacier, Central Caucasus, Russia. The spectra of the samples containing mineral dust transported from deserts were characterized by negative visible near-infrared gradients and were different from the spectra of clean aged snow and exposed glacier ice and from the samples containing mineral dust produced locally. Geochemical and mineralogical analysis using X-ray diffraction and X-ray fluorescence spectrometry showed that samples containing desert dust were characterised by a high proportion of clay materials and such minerals as smectites, illite–smectites and palygorskite and by a smaller size of mineral particles. They were enriched in chromium, zinc and vanadium. The latter served as an indicator of dust transport over or origin from the oil-producing regions of the Middle East. There was a strong negative correlation between the amount of organic matter and mineral dust in the collected samples and the albedo of surfaces from which the samples were collected. The results suggested that organic matter reduced albedo more efficiently than mineral dust. The study highlighted the importance of supra-glacial material in changing the surface reflectivity of snow and glaciers in the Caucasus region. |
| Databáze: | OpenAIRE |
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