Up to 30% of the current tidewater mass loss in Svalbard corresponds to frontal ablation through submarine melting and calving. We developed two-dimensional (2-D) glacier–line–plume and glacier–fjord circulation coupled models, both including subglacial discharge, submarine melting and iceberg calving, to simulate Hansbreen–Hansbukta system, SW Svalbard. We ran both models for 20 weeks, throughout April–August 2010, using different scenarios of subglacial discharge and crevasse water depth. Both models showed large seasonal variations of submarine melting in response to transient fjord temperatures and subglacial discharges. Subglacial discharge intensity and crevasse water depth influenced calving rates. Using the best-fit configuration for both parameters our two coupled models predicted observed front positions reasonably well (±10 m). Although the two models showed different melt-undercutting front shapes, which affected the net-stress fields near the glacier front, no significant effects on the simulated glacier front positions were found. Cumulative calving (91 and 94 m) and submarine melting (108 and 118 m) along the simulated period showed in both models (glacier–plume and glacier–fjord) a 1:1.2 ratio of linear frontal ablation between the two mechanisms. Overall, both models performed well on predicting observed front positions when best-fit subglacial discharges were imposed, the glacier–plume model being 50 times computationally faster.

中文翻译：

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冰川-地幔柱还是冰川-峡湾环流模型？Hansbreen-Hansbukta 系统的二维比较，斯瓦尔巴群岛

斯瓦尔巴群岛目前高达 30% 的潮水质量损失对应于海底融化和崩解造成的正面消融。我们开发了二维 (2-D) 冰川-线-羽流和冰川-峡湾环流耦合模型，包括冰下排放、海底融化和冰山崩解，以模拟斯瓦尔巴群岛西南部的 Hansbreen-Hansbukta 系统。我们在 2010 年 4 月至 8 月期间运行这两个模型 20 周，使用不同的冰下排放和裂缝水深情景。两种模型都显示了海底融化响应瞬态峡湾温度和冰下排放的巨大季节性变化。冰下排放强度和裂缝水深影响产犊率。使用两个参数的最佳拟合配置，我们的两个耦合模型可以很好地预测观察到的前沿位置（±10 m）。虽然两个模型显示出不同的熔体底切锋面形状，影响了冰川锋面附近的净应力场，但没有发现对模拟的冰川锋面位置有显着影响。模拟期间的累积崩解（91 和 94 m）和海底融化（108 和 118 m）在两个模型（冰川-羽流和冰川-峡湾）中显示，两种机制之间的线性正面消融比率为 1:1.2。总体而言，当施加最佳拟合冰下放电时，两种模型在预测观察到的前沿位置方面表现良好，冰川-羽流模型的计算速度提高了 50 倍。模拟期间的累积崩解（91 和 94 m）和海底融化（108 和 118 m）在两个模型（冰川-羽流和冰川-峡湾）中显示，两种机制之间的线性正面消融比率为 1:1.2。总体而言，当施加最佳拟合冰下放电时，两种模型在预测观察到的前沿位置方面表现良好，冰川-羽流模型的计算速度提高了 50 倍。模拟期间的累积崩解（91 和 94 m）和海底融化（108 和 118 m）在两个模型（冰川-羽流和冰川-峡湾）中显示，两种机制之间的线性正面消融比率为 1:1.2。总体而言，当施加最佳拟合冰下放电时，两种模型在预测观察到的前沿位置方面表现良好，冰川-羽流模型的计算速度提高了 50 倍。