冰盖反馈对冰川和冰下水文的影响
Groundwater feedbacks on ice sheets and subglacial hydrology
AI总结：
本文研究了沉积盆地对冰川滑动和退缩的影响，发现地下水排泄促进滑动，而补给抑制滑动，并揭示了沉积盆地在冰川动力学中的重要性。
摘要：
南极许多冰川的动力学受到冰层底部的水文系统调节。冰下沉积盆地通过排泄或吸收水来贡献该水文系统的水预算。然而，这些沉积盆地目前大多数冰动力学模型中并未包含，对其影响了解甚少。本文开发了一个简化的冰川模型，其滑动与冰下水文系统耦合，该系统包括沉积盆地。我们发现地下水排泄（出渗）和补给（入渗）受冰盖和沉积盆地形状控制，出渗促进滑动而入渗抑制滑动。总体而言，沉积盆地的存在导致稳态下冰层更厚且流动更缓慢。我们还发现，当冰盖退缩时，地下水出渗可能产生正反馈，加速退缩过程。我们的结果揭示了南极沉积盆地的潜在作用和重要性，以及如何将这些纳入现有冰和冰下水文模型中。
英文摘要：
The dynamics of many of Antarctica's glaciers are modulated by a hydrological system at the base of the ice. Sedimentary basins beneath the ice bed contribute to the water budget in this hydrological system by discharging or taking up water. However, sedimentary basins are not included in most current models of ice dynamics, and little is known about their effect. In this paper we develop an idealised model of a glacier whose sliding is coupled to a subglacial hydrological system, which includes a sedimentary basin. We find that groundwater discharge (exfiltration) and recharge (infiltration) are controlled by the shape of the ice sheet and of the sedimentary basin, and that exfiltration promotes sliding whereas infiltration hinders it. Overall, the presence of a sedimentary basin leads to thicker and slower-flowing ice in the steady state. We also find that, when the ice sheet is undergoing retreating, groundwater exfiltration can lead to a positive feedback which accelerates this retreat. Our results shed light on the potential role and importance of Antarctic sedimentary basins, and how these might be incorporated into existing models of ice and subglacial hydrology.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
