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

高纬度气候变化的复杂性给对大气环流感兴趣的研究人员带来了许多挑战。例如，过去两年包括有史以来最极端的北极海冰最小值和北方半球积雪从春季到夏季最快的消退。这些年也出现了极端的中纬度天气事件，一些研究人员推测这与最近的北极变化有关。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，并与大气和海洋的行星尺度环流的变化有关。但是，气候模式并没有有力地预测高纬度气候变化的关键方面，气候反馈和与大气和海洋行星尺度环流的动力耦合仍然知之甚少。 PI领导了一个原始的基础研究计划，其长期目标是更好地了解热带以外的大气环流，其在十年时间尺度上的变化，对气候变化的敏感性以及与环境的耦合。此外，在过去的六年里，他开发并领导了一个北极和冰冻圈建模的合作应用研究项目，重点是季节性到十年时间尺度上的积雪和海冰预测。PI的基础研究计划集中在气候模型的层次结构上，从大气简化表示的新配置到最先进的地球系统模型（ESM），这些模型努力包括控制地球气候的物理，生物和化学过程。这个基础研究计划是需要的PI能够利用他的应用工作，以改善气候预测和推进我们对气候的理解。 PI的研究目标是长期推进大气环流理论。它的主要应用是针对高纬度地区的气候变化和可变性。这项发现补助金计划旨在支持PI未来六年的基础研究计划。 该研究在未来六年的目标是 *1）了解高纬度气候如何与大气行星波相关的变化联系在一起，重点是PI小组在开创性研究中探索的所谓“线性干扰效应”。2)使用复杂程度不同的气候模型层次来理解中纬度和极地变化之间的双向联系，这是PI成功的理论研究的标志。3)利用加拿大和国际计算资源生成一套全面的ESM模拟，确定控制中纬度十年期气候信号持续性和可预测性的耦合海洋大气系统中的机制。4)通过合作研究，在湖泊动态研究的背景下，有针对性地分析北极变化对北极环境的影响。湖泊工作将把联合收割机气象分析与数十年的北极湖泊记录结合起来，并将区域模型描述当今条件和预计全球变暖的条件。PI拥有一批优秀的本科生，研究生，博士后研究员和研究助理，以支持他的研究计划;他们接受严格的培训，并因此在专业上取得了很好的进步。提案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记录和后续安置。

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 are*1) 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.