Eurasian ice-sheet dynamics and sensitivity to subglacial hydrology
| Autor: | Sebastian Beyer, Karin Andreassen, Angelika Humbert, Eythor Gudlaugsson, Thomas Kleiner, Caroline Clason |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
010506 paleontology
Ice-sheet dynamics 010504 meteorology & atmospheric sciences Water flow Flow (psychology) Fast flow 01 natural sciences Hydrology (agriculture) VDP::Matematikk og Naturvitenskap: 400::Geofag: 450 subglacial lakes Geomorphology glacier hydrology 0105 earth and related environmental sciences Earth-Surface Processes Hydrology geography VDP::Mathematics and natural science: 400::Geosciences: 450 geography.geographical_feature_category Sediment 15. Life on land Subglacial stream 13. Climate action ice-sheet modelling Ice sheet ice dynamics Geology |
| Zdroj: | EPIC3Journal of Glaciology, Cambridge University Press, 63(239), pp. 556-564, ISSN: 0022-1430 |
| ISSN: | 1727-5652 0022-1430 |
| DOI: | 10.1017/jog.2017.21 |
| Popis: | Ice-stream dynamics are strongly controlled by processes taking place at the ice/bed interface where subglacial water both lubricates the base and saturates any existing, underlying sediment. Large parts of the former Eurasian ice sheet were underlain by thick sequences of soft, marine sediments and many areas are imprinted with geomorphological features indicative of fast flow and wet basal conditions. Here, we study the effect of subglacial water on past Eurasian ice-sheet dynamics by incorporating a thin-film model of basal water flow into the ice-sheet model SICOPOLIS and use it to better represent flow in temperate areas. The adjunction of subglacial hydrology results in a smaller ice-sheet building up over time and generally faster ice velocities, which consequently reduces the total area fraction of temperate basal ice and ice streaming areas. Minima in the hydraulic pressure potential, governing water flow, are used as indicators for potential locations of past subglacial lakes and a probability distribution of lake existence is presented based on estimated lake depth and longevity. |
| Databáze: | OpenAIRE |
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