Over-winter persistence of supraglacial lakes on the Greenland Ice Sheet: Results and insights from a new model
<jats:title>Abstract</jats:title><jats:p>We present a newly developed 1-D numerical energy-balance and phase transition supraglacial lake model: GlacierLake. GlacierLake incorporates snowfall, in situ snow and ice melt, incoming water from the surrounding catchment, ice lid formati...
Main Authors: | , , , , , |
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Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Cambridge University Press (CUP)
2020
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Subjects: | |
Online Access: | https://www.repository.cam.ac.uk/handle/1810/300845 https://doi.org/10.17863/CAM.47922 |
Summary: | <jats:title>Abstract</jats:title><jats:p>We present a newly developed 1-D numerical energy-balance and phase transition supraglacial lake model: GlacierLake. GlacierLake incorporates snowfall, in situ snow and ice melt, incoming water from the surrounding catchment, ice lid formation, basal freeze-up and thermal stratification. Snow cover and temperature are varied to test lake development through winter and the maximum lid thickness is recorded. Average wintertime temperatures of −2 to<jats:inline-formula><jats:alternatives><jats:tex-math>$-30^{\circ }{\rm C}$</jats:tex-math><jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" mime-subtype="png" mimetype="image" xlink:href="S0022143020000076_inline2.png" /></jats:alternatives></jats:inline-formula>and total snowfall of 0 to 3.45 m lead to a range of the maximum lid thickness from 1.2 to 2.8 m after<jats:inline-formula><jats:alternatives><jats:tex-math>${\sim }250$</jats:tex-math><jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" mime-subtype="png" mimetype="image" xlink:href="S0022143020000076_inline3.png" /></jats:alternatives></jats:inline-formula>days, with snow cover exerting the dominant control. An initial ice temperature of<jats:inline-formula><jats:alternatives><jats:tex-math>$-15^{\circ }{\rm C}$</jats:tex-math><jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" mime-subtype="png" mimetype="image" xlink:href="S0022143020000076_inline4.png" /></jats:alternatives></jats:inline-formula>with simulated advection of cold ice from upstream results in 0.6 m of basal freeze-up. This suggests that lakes with water depths above 1.3 to 3.4 m (dependent on winter snowfall and temperature) upon lid formation will persist through winter. These buried lakes can provide a sizeable water store at the start of the melt season, expedite future lake formation and warm underlying ice even in ... |
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