UK SWAIS 2C

英国SWAI 2C

• 批准号: NE/X00936X/1
• 负责人: Edward Gasson
• 金额: $ 51.21万
• 依托单位: UNIVERSITY OF EXETER
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2024
• 资助国家: 英国
• 起止时间: 2024 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FX00936X%2F1
• 关键词: UK; SWAIS; 2C

As our planet is warming, global mean sea level is rising. Since the year 1900 this rise in sea level has been ~ 20 cm, initially due to the expansion of water under warmer temperatures and melting of mountain glaciers. However, over recent years the melting of the large ice sheets on Greenland and Antarctica has increased significantly, and loss of land ice (glaciers and ice sheets) is now the largest contributor to global mean sea level. The polar ice sheets hold many tens of metres of sea level equivalent, but are slow to respond to enhanced greenhouse gas emissions (i.e. slower than global temperatures). With every degree of warming, society is hence facing a long-term commitment in sea level rise for centuries and millennia into the future. This is true, even if global emissions would be halted tomorrow, and future warming would be kept below 2 degrees C, the target set by the Paris agreement in 2015. The West Antarctic Ice Sheet (WAIS) holds 4.3 m of sea level equivalent and is the part of Antarctica where most mass loss is observed today. This motivated the formation of an international consortium to recover sediments from two drill sites in the Ross Sea (Antarctica) to answer the following question: 'What is the sensitivity of the WAIS to 2C warming'. This proposal presents the case how the UK community could best contribute and lead in answering this critical question by combining our unique expertise in generating combined data and modelling approaches to address three objectives: (1) What was the configuration of the WAIS during past warm periods? (2) How did the WAIS retreat and readvance in the geological past? (3) How do changes in the Antarctic landscape through time affect ice dynamics? We will use advanced laboratory methodologies to determine the chemical fingerprint of sediments and how this relates to where on the continent the sediment came from, when it was last exposed, how close to the ice sheet margin it was deposited and under what environmental conditions. By using this information in numerical models, we will overcome a longstanding limitation that the models used to predict the future are often providing contrasting results on past ice sheet configurations. We will use a hierarchy of models, from simple ice sheet models to advanced coupled ice sheet and climate models to develop a more accurate picture of past WAIS dynamics and mechanisms in relation to ocean warming, atmospheric warming, and changing topography on land, consistent with observations from ice cores and marine sediment cores.

随着地球变暖，全球平均海平面正在上升。自 1900 年以来，海平面上升了约 20 厘米，最初是由于气温升高和山区冰川融化导致水膨胀。然而，近年来，格陵兰岛和南极洲大冰盖的融化显着增加，陆地冰（冰川和冰盖）的损失现在是全球平均海平面的最大贡献者。极地冰盖相当于海平面数十米，但对温室气体排放增加的反应缓慢（即慢于全球气温）。随着每一次变暖，社会都面临着未来几个世纪和几千年海平面上升的长期承诺。即使全球明天停止排放，未来气温升高将保持在 2 摄氏度以下（这是 2015 年《巴黎协定》设定的目标），情况也是如此。南极西部冰盖 (WAIS) 的海平面高度相当于 4.3 m，并且是今天观测到的南极洲质量损失最多的部分。这促使成立一个国际财团，从罗斯海（南极洲）的两个钻探地点回收沉积物，以回答以下问题：“WAIS 对 2 摄氏度变暖的敏感性是什么”。该提案展示了英国社区如何通过结合我们在生成组合数据和建模方法方面的独特专业知识来最好地贡献和引领回答这一关键问题，以实现三个目标：(1) 过去温暖时期 WAIS 的配置是什么？ (2) WAIS在地质历史上是如何后退和再前进的？ (3) 南极地貌随时间的变化如何影响冰动态？我们将使用先进的实验室方法来确定沉积物的化学指纹，以及这与沉积物来自大陆的位置、最后一次暴露的时间、沉积物距离冰盖边缘有多近以及在什么环境条件下沉积的关系。通过在数值模型中使用这些信息，我们将克服一个长期存在的限制，即用于预测未来的模型通常会提供与过去冰盖配置相反的结果。我们将使用一系列模型，从简单的冰盖模型到先进的冰盖和气候耦合模型，更准确地了解过去的 WAIS 动态和与海洋变暖、大气变暖和陆地地形变化相关的机制，与来自冰芯和海洋沉积物岩心的观测。