Global sea level change since the Mid Holocene: Background trends and climate-ice sheet feedbacks

在过去的几十年里，格陵兰岛和南极洲的冰盖对海平面上升的贡献有所增加。然而，目前尚不清楚最近陆地冰量的减少在多大程度上与全球气候变暖有关。我们的目标是评估与工业时期变化有关的冰盖质量平衡的自然变化和长期趋势。为此目的，我们把我们的注意力转向过去6000年，从全新世中期到现在，因为这一时期的特点是类似于目前的冰盖几何形状，以及温和和渐进的气候变化开始之前，温室气体浓度上升。该项目的基础是格陵兰岛和南极洲在过去6000年的冰盖变化，结合冰盖模拟和气候模拟在不同的空间和时间尺度上运行。此外，我们将重点关注气候系统和冰盖之间的相互作用，这通常是在千年尺度的模拟解决。特别是，我们将分析--过去6000年来两个冰盖对气候变化的响应--小尺度海洋-冰架相互作用对南极洲周围冰架空腔中基底融化速率的影响--与格陵兰融化水径流相关的冰盖-气候反馈--不同基底融化情景对南极洲物质平衡的影响--基底熔融的潜在参数化技术，这是可行的地球系统模拟的长时间尺度。

Over the last few decades the contribution of the ice sheets of Greenland and Antarctica to sea-level rise has grown. It is however not clear to what extent the recent reduction in land ice mass is related to the globally warming climate. We aim to assess natural variability and long-term trends in the ice sheet´s mass balance in relation to changes during the industrial period. For this purpose we turn our attention to the last 6000 years, from Mid Holocene to present, as this period is characterized by similar to present ice sheet geometries as well as moderate and gradual climate change before the onset of rising greenhouse gas concentration. The base of this project focuses on ice sheet variations of Greenland and Antarctica over the last 6000 years, combining ice sheet simulation and climate simulations operating on different spatial and temporal scales. Additionally we will focus on interactions between the climate system and the ice sheets, which are usually unresolved in millennial scale simulations. In particular, we will analyze - the response of the two ice sheets to climate variations over the last 6000 years - the small scale ocean-ice shelf interaction on the basal melt rates in ice shelf cavities around Antarctica - the ice sheet-climate feedbacks associated with Greenland melt water runoff - the impact of different basal melt scenarios on the mass balance of Antarctica - the skill of potential parameterizations of basal melting, which are feasible for Earth system modeling on long time scales.