Over-winter persistence of supraglacial lakes on the Greenland Ice Sheet: Results and insights from a new model ...

• Main Authors: Law, R, Arnold, N, Benedek, C, Tedesco, M, Banwell, A, Willis, I
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 2020
• Subjects: glacier hydrology; melt-surface; glacier modelling; Greenland; glacier; Ice Sheet
• Online Access: https://dx.doi.org/10.17863/cam.47922; https://www.repository.cam.ac.uk/handle/1810/300845

AbstractWe 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$-30^{\circ }{\rm C}$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${\sim }250$days, with snow cover exerting the dominant control. An initial ice temperature of$-15^{\circ }{\rm C}$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 ...