A Theoretical Study of Climate Dynamics

王0072612 研究者研究了大尺度地球物理流体流的结构、其鲁棒性和稳定性以及转换，以更好地理解与气候低频变率的典型来源相关的这些流体流的预测和可预测性。 本工作研究了两个领域的具体问题：1）连续方程的理论问题，2）年际变率特征对模型参数在底层物理空间中变化的存在、敏感性和鲁棒性。 在第一区，研究者研究了大尺度海洋/大气流动的原始方程。 具体问题包括原始方程和相关的简单模式的稳定性和分叉问题，特别是在气候低频变率方面。 区域2的主要目标是对与边界层现象有关的典型大尺度大气/海洋环流流型进行分类，并研究它们的结构分叉。 这一领域的部分工作是基于最近由牛顿和T. MA. 研究人员使用物理模型，渐近方法，严格的数学理论和大规模计算的组合，以产生对物理现象的新见解。 这项工作涉及与大气/海洋科学家的具体合作。 本项目的主要目标是通过细致的理论研究，记录北美大陆附近海洋盆地中存在的有规律的年际和年代际变化，验证这种变化特征对模式参数变化的鲁棒性，并帮助解释其物理机制。 对这种变率的透彻理解对于确定气候系统的可预报性和在次大陆和更小的空间尺度上的预测是至关重要的，因为时间尺度等于或超过几年。 相关的现象包括由风驱动的双环流海洋环流和厄尔尼诺-南方涛动现象，这些现象主导着太平洋大部分地区乃至全世界的年际气候变率。 这些研究可能会改善天气、气候和环境现象的预测。

Wang0072612 The investigator studies the structure, its robustness andstability, and the transitions of large scale geophysical fluidflows, to arrive at a better understanding of the prediction andpredictability of these flows relevant to the typical sources oflow frequency variabilities in climate. The work studies specifictopics in two areas: 1) theoretical issues of the primitiveequations, and 2) the presence, sensitivity and robustness ofinterannual variability characteristics to changes in modelparameters in the underlying physical space. In Area 1, theinvestigator studies the primitive equations of large scaleocean/atmosphere flows. Specific problems include stability andbifurcation issues of the primitive equations and related simplermodels, especially in connection to climate low frequencyvariabilities. The main objectives in Area 2 are to classifytypical large scale atmosphere/ocean circulation flow patternsassociated with boundary layer phenomena, and to study theirstructural bifurcations. Part of the work in this area is basedon a new geometric theory developed recently by the investigatorand T. Ma. The investigator uses a combination of physicalmodelling, asymptotic methods, rigorous mathematical theory, andlarge scale computing to yield new insights into physicalphenomena. The work involves specific collaborations withatmosphere/ocean scientists. The primary goal of this project is to document, throughcareful theoretical studies, the presence of regular interannualand interdecadal variability in the ocean basins adjacent to theNorth American continent, to verify the robustness of thisvariability's characteristics to changes in model parameters, andto help explain its physical mechanisms. The thoroughunderstanding of this variability is of the essence indetermining the climate system's predictability and prediction onsubcontinental and smaller spatial scales, for time scales thatequal and exceed a few years. The associated phenomena includethe double-gyre wind-driven ocean circulation and the ElNino-Southern Oscillation (ENSO) phenomenon, which dominatesinter-annual climate variability over much of the Pacific Ocean,and hence the world. The studies could lead to improvedpredictions of weather, climate, and environmental phenomena.