THINNING HISTORY OF THE FOUNDATION-THIEL TROUGH ICE STREAM: A KEY CONTROL ON DEGLACIATION OF THE WEST ANTARCTIC ICE SHEET, WEDDELL SEA EMBAYMENT

南极冰盖是地球上最大的冰盖，任何不稳定都可能主导全球海平面变化。因此，我们需要冰盖模型来对未来的变化做出更可靠和更有力的预测。在迎接这一挑战的一个问题是缺乏过去的冰川消退数据，初始化和校准模型。这一问题在威德尔海海湾尤其是其东部尤为严重，在那里，基金会-蒂尔海槽一直是西南极冰盖的主要排水路线，其南部延伸部分可能是未来不稳定的潜在地点。我们在这里提出了一个综合的领域和建模研究，将利用来自一系列不同学科的几个新兴领域数据集的机会，从一个关键位置收集新的数据，并使用复杂的冰盖模型调查过去和未来的冰川消退。为了了解冰变薄的历史和沿着海槽后退，我们将采用量油尺方法来调查基金会冰流，这是上一个冰河时代占据海槽的冰流的上游延伸。我们将从地貌学和暴露年龄测定确定这一基础-蒂尔槽冰流的变薄历史：这些技术已被有效地用于深入了解南极洲其他地区的冰盖历史。我们将应用一个3D模型-结合最近的重大理论进展-整个WAIS，以了解我们测量的冰流历史的强迫机制。我们将继续使用这个模型来预测WAIS在长期轨迹和对气候变化情景的任何响应方面可能的未来稳定性，特别是它是否会沿着基础-蒂尔槽进一步沿着。

The Antarctic ice sheet is the largest on earth and any instability is likely to dominate global sea level change. We therefore require models of the ice sheet to make more reliable and robust predictions of future change. One problem in meeting this challenge is the lack of past data on deglaciation with which to initialize and calibrate the models. This problem has been particularly acute in the Weddell Sea embayment and in particular its eastern part where the Foundation - Thiel Trough has been a principal drainage route for the West Antarctic Ice Sheet (WAIS), and its southern extension may be a potential location for future instability. We propose here an integrated field and modelling study that will exploit the opportunity of several emerging field datasets from a range of different disciplines, collect fresh data from a crucial location, and investigate past and future deglaciation using sophisticated ice sheet models. To understand the history of ice thinning and retreat along the trough we will adopt a dipstick approach to survey the Foundation Ice Stream, an upstream extension of the ice stream that occupied the trough during the last ice age. We will determine the thinning history of this Foundation-Thiel Trough Ice Stream from geomorphology and exposure age dating: techniques that have been used effectively to provide insight into ice sheet history in other regions of Antarctica. We will apply a 3D model - incorporating significant recent theoretical advances - to the whole of the WAIS in order to understand the forcing mechanisms for the ice stream history we measure. We will go on to use this model to predict the likely future stability of the WAIS in terms of both long-term trajectory and any response to climate change scenarios, and in particular whether it will retreat further along the Foundation-Thiel Trough.