Theory of the atmospheric general circulation: coupling to polar climate and cryospheric change.

高纬度地区气候变化的复杂性给对大气环流感兴趣的研究人员提出了许多挑战。例如，过去两年包括最极端的北极海冰最少和北半球有记录以来从春季到夏季最快的积雪消退。这几年还出现了极端中纬度天气事件，一些研究人员推测这与最近北极的变化有关。高纬度地区的快速气候变化是在长期人为全球变化的背景下发生的，受到气候反馈的强烈影响，并与全球范围大气和海洋环流的变化有关。但是，气候模型并不能很好地预测高纬度气候变化的关键方面，气候反馈以及与大气和海洋的行星尺度环流的动力耦合仍然知之甚少。PI领导着一个原创的基础研究计划，其长期目标是更好地了解热带以外的大气环流，它在十年时间尺度上的变异性，它对气候变化的敏感性，以及它与环境的耦合。此外，在过去六年中，他开发并领导了一个北极和冰冻圈建模方面的合作应用研究计划，重点是预测季节性到十年时间尺度上的积雪和海冰。PI的基础研究计划集中在气候模型的层次结构上，从简化的大气表示的新颖配置到致力于包括控制地球气候的物理、生物和化学过程的最先进的地球系统模型(ESM)。这一基础研究计划是PI能够利用他的应用工作来改进气候预测和促进我们对气候的理解所必需的。从长远来看，国际大气研究所的研究目标是推进大气环流理论。它的主要应用是应对高纬度地区的气候变化和可变性。这项探索奖助金计划旨在支持国际和平研究所未来六年的基础研究计划。未来六年的研究目标是1)了解高纬度气候如何与与大气行星波有关的可变性联系在一起，重点是PI的小组在开创性研究中探索的所谓的“线性干扰效应”。2)使用不同复杂程度的气候模式体系来了解中纬度和极地可变性之间的双向联系，这一直是PI成功的理论研究的标志。3)确定耦合海洋大气系统中控制中纬度气候信号的持续性和可预测性的机制，4)通过合作研究，在湖泊动力学研究的背景下，有针对性地分析北极多变对北极环境的影响。湖泊工作将结合气象分析和数十年的北冰洋湖泊记录，以及对当今状况和全球变暖预测条件的区域模式表示。Pi拥有一批优秀的本科生、研究生、博士后研究员和研究人员来支持他的研究计划，他们受到严格的培训，因此在专业上取得了良好的进步。建议中要求的资源将主要用于支持学生，并旨在继续申请人的高水平培训和后续安置的记录。

The complexity of climate change at high latitudes presents many challenges to researchers interested in the atmospheric general circulation. For example, the last two years included the most extreme Artic sea ice minimum and the most rapid spring-to-summer retreat of Northern Hemisphere snow cover ever recorded. These years also featured extreme midlatitude weather events which some researchers have speculated are linked to recent Arctic change. Rapid climate change at high latitudes is taking place in the context of long term anthropogenic global change, is strongly influenced by climate feedbacks, and is connected to changes in the planetary scale general circulation of the atmosphere and oceans. But key aspects of high latitude climate change are not robustly predicted by climate models, and the climate feedbacks and dynamical coupling to the planetary-scale circulation of the atmosphere and oceans remain poorly understood. The PI leads an original basic research program whose long term objective is to better understand the atmospheric circulation outside the tropics, its variability on decadal timescales, its sensitivity to climate change, and its coupling to the environment. Alongside, in the last six years, he has developed and now leads a collaborative applied research program in Arctic and cryospheric modelling, focusing on prediction of snow cover and sea ice on seasonal to decadal timescales. The PI's basic research program centres on a hierarchy of climate models that ranges from novel configurations of simplified representations of the atmosphere to state of the art Earth System Models (ESMs) that endeavour to include the physical, biological, and chemical processes controlling Earth's climate. This basic research program is needed for the PI to be able to leverage his applied work to improve climate prediction and advance our understanding of climate. The PI's research aims, over the long term, to advance the theory of the atmospheric general circulation. Its primary application is towards climate change and variability at high latitudes. This Discovery Grant proposal is intended to support the PI’s basic research program for the next six years. The research's objectives over the next six years are1) To learn how high latitude climate is linked to variability associated with atmospheric planetary waves, with a focus on a so-called "linear interference effect" that the PI's group has explored in groundbreaking research.2) To understand the two-way connections between midlatitude and polar variability using a hierarchy of climate models of varying degrees of complexity, which has been a hallmark of the PI's successful theoretical research.3) To identify mechanisms in the coupled ocean atmosphere system controlling persistence and predictability of decadal climate signals in the midlatitudes, with a suite of comprehensive ESM simulations being generated using Canadian and international computing resources.4) To carry out targeted analysis on the impact of Arctic variability on the Arctic environment in the setting of lake dynamics studies, through collaborative research. The lake work will combine meteorological analysis with multiple-decade long Arctic lake records, as well as regional model representations of present day conditions and under conditions of projected global warming.The PI maintains a group of excellent undergraduate students, graduate students, postdoctoral fellows, and research associates to support his research program; they receive rigorous training and as a result advance well professionally. Resources requested in the proposal will go mainly to support students, and are intended to continue the applicant’s track record of high level training and follow on placement.