Abrupt climate and sea level change

这个博士项目将使用数值模拟来研究快速气候和海平面变化的原因和后果。过去冰川消融的案例研究将被用来对冰盖融化与海平面上升、快速冷却、突然变暖和大西洋环流完全重组之间的联系达到一个新的认识水平。在末次冰盛期（21000年前），巨大的冰盖覆盖了北半球的大部分地区。随着气候变暖，冰开始融化，引发了一系列有趣而灾难性的事件：大规模的海洋环流减缓，气候变冷，冰山舰队被释放，海平面以前所未有的速度上升，海洋环流迅速加强，气温在几十年内突然上升了几度……几个世纪后，这一切又发生了。尽管有详细的文献记载，但我们仍然不知道这些事件是如何联系的，甚至不知道这些事件是否有联系。也许更有趣的是，我们知道许多事件在地球过去反复发生，这表明地球系统中有一致但目前未知的触发气候突变的机制。科学界对这些事件的起因仍存在分歧，但一致认为，为了预测它们何时发生，了解这些机制是很重要的。随着未来几年大气中二氧化碳含量的上升，格陵兰岛和南极冰盖继续融化，这些灾难性事件会再次引发吗？这个令人兴奋的项目将直接解决这一挑战，测试冰川消融期间发生的冰-海洋-大气相互作用，以产生有关气候的开创性新知识。你将成为两个国际项目的核心，为过去的突变气候变化提供新的模式模拟和观测记录：古气候模式比较项目（PMIP）冰川消融工作组和国际第四纪研究联盟冰川消融焦点小组，这两个项目都由Ruza Ivanovic博士协调。因此，您将获得世界领先科学家的最新成果和思想，并且处于国际研究过去变暖气候的前沿，您将有机会参与全球研究议程。你将运行和分析复杂的数值地球系统模型，以研究气候、冰盖、冰山和海洋环流之间的相互作用。你将把这些模拟的结果与观测记录进行比较，以评估模型的性能，验证/反驳对事件的现有解释，并建立和测试新的假设。总体目标是建立连接地球系统中冰、大气和海洋的机制，然后探索我们所知道的过去发生过的这种快速和灾难性事件在未来再次发生的可能性。

This PhD project will use numerical modelling to examine the causes and consequences of rapid climate and sea level change. Case studies from past deglaciations will be utilised to reach a new level of understanding for the link between ice sheet melting and sea level rise, rapid cooling, abrupt warming and the complete reorganisation of Atlantic Ocean circulation.At the Last Glacial Maximum (21,000 years ago), vast ice sheets stretched across much of the Northern Hemisphere. As climate warmed and the ice began melting, an intriguing and catastrophic chain of events was triggered: Largescale ocean circulation slowed, climate cooled, armadas of icebergs were released, sea level rose at an unprecedented rate, ocean circulation rapidly strengthened, temperatures suddenly increased by several degrees in a few decades...and then it all happened again just a few centuries later. Although well documented individually, we still do not know precisely how and even if these events are linked. Perhaps even more intriguingly, we know that many of the events have occurred repeatedly in Earth's past, suggesting there are consistent but currently unknown mechanisms in the Earth System for triggering abrupt climate change.The scientific community remains divided on the cause of the events, but there is consensus that the mechanisms are important to understand in order to predict when they will occur. As atmospheric CO2 rises in the coming years, and the Greenland and Antarctic ice sheets continue to melt, could these catastrophic events be triggered again?This exciting project will tackle this challenge directly, testing ice-ocean-atmosphere interactions that take place during deglaciations in order to produce seminal new knowledge on our climate. You will be at the heart of two international projects producing new model simulations and observational records of past abrupt climate change: The Paleoclimate Model Intercomparison Project (PMIP) Deglaciations Working Group and The International Union for Quaternary Research Focus Group on Deglaciations, both coordinated by Dr. Ruza Ivanovic. Thus, you will be granted access to the latest results and thinking from world-leading scientists, and, positioned at the forefront of international research into past warming climates, you will have the opportunity to feed into the global research agenda.PROJECT AIMYou will run and analyse complex numerical earth system models to examine the interplay between climate, ice sheets, icebergs and ocean circulation. You will compare the results from these simulations to observational records to evaluate model performance, verify/refute existing explanations for the events, and build and test new hypotheses. The overall aim is to establish the mechanisms that link ice, atmosphere and ocean in the Earth System, then explore the possibility that such rapid and catastrophic events as we know have occurred in the past will occur again in the future.