Modeling the Influence of Moulin Shape on Subglacial Hydrology

التفاصيل البيبلوغرافية
العنوان: Modeling the Influence of Moulin Shape on Subglacial Hydrology
المؤلفون: Celia Trunz, Matthew D. Covington, Kristin Poinar, Lauren Andrews, Jessica Mejia, Jason Gulley
المصدر: Journal of Geophysical Research - Earth Surface. 127(8)
بيانات النشر: United States: NASA Center for Aerospace Information (CASI), 2022.
سنة النشر: 2022
مصطلحات موضوعية: Earth Resources And Remote Sensing, Geophysics
الوصف: Subglacial models represent moulins as cylinders or cones, but field observations suggest that the upper part of moulins in the Greenland Ice Sheet has more complex shapes. These more complex shapes should cause englacial water storage within moulins to vary as a function of depth, a relationship not currently accounted for in models. Here, we use a coupled englacial-subglacial channel model to explore how moulin shape affects depth-dependent moulin water storage and water pressure dynamics within a subglacial channel. We simulate seven different moulin shapes across a range of moulin sizes. We find that the englacial storage capacity at the water level is the main control over the daily water level oscillation range and that depth-varying changes in englacial water storage control the temporal shape of this oscillation. Further, the cross-sectional area of the moulin within the daily oscillation range, but not above or below this range, controls pressures within the connected subglacial channel. Specifically, large cross-sectional areas can dampen daily to weekly oscillations that occur in the surface meltwater supply. Our findings suggest that further knowledge of the shape of moulins around the equilibrium water level would improve englacial storage parameterization in subglacial hydrological models and aid predictions of hydrodynamic coupling.
نوع الوثيقة: Report
اللغة: English
تدمد: 2169-9011
DOI: 10.1029/2022JF006674
URL الوصول: https://ntrs.nasa.gov/citations/20220012637
ملاحظات: 281945.02.53.04.24

NSF 1604022

NASA Cryosphere 80NSSC19K0054
رقم الأكسشن: edsnas.20220012637
قاعدة البيانات: NASA Technical Reports
الوصف
تدمد:21699011
DOI:10.1029/2022JF006674