NSFGEO-NERC: Large-Scale Atmospheric Circulation Response to Oyashio Extension Frontal Variability

NSFGEO-NERC：大规模大气环流对 Oyashio 扩展锋面变化的响应

• 批准号: 2040073
• 负责人: Young-Oh Kwon
• 金额: $ 86.03万
• 依托单位: Woods Hole Oceanographic Institution
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-02-01 至 2025-01-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2040073&HistoricalAwards=false
• 关键词: NSFGEO; NERC; Large; Scale; Atmospheric

Winter over the North Pacific features an endless parade of frontal storms, forming near Japan and building as they cross the ocean to reach North America. Model simulations can produce realistic North Pacific storms even if the sea surface temperatures (SSTs) are held fixed, indicating that the storms owe their existence to the strong upper-level jet stream and accompanying north-south atmopsheric temperature contrast rather than air-sea interactions. Nevertheless there are intriguing hints that storm behavior can be influenced by variations in the underlying SSTs, and some indications that slowly varying SSTs may change storm paths and behavior in ways that could prove useful for making long-range weather predictions. The SST variations of interest occur as a result of the meandering of the Kuroshio-Oyashio Extension (KOE), a narrow ocean current that extends into the Pacific from the coast of Japan. The KOE is a warm current and the sharp temperature contrast between the current and the cold water north of it produces relatively strong SST variations when the KOE shifts to the north or south.Attempts to identify and analyze the influence of KOE-related SST variations on storms and atmospheric circulation have had mixed results. But recent work by the Principal Investigators (PIs) and others suggests that the key to capturing the atmospheric response is to dramatically increase the resolution of atmospheric models used for this purpose. In particular the PIs have developed a variable resolution version of the Community Atmosphere Model version 6 (VR-CAM6) which takes advantage of the spectral element dynamical core to increase resolution over the North Pacific (a box from 20N to 60N and 130E to 110W). The lower resolution outside the North Pacific allows the model to be run cheaply enough to allow large ensembles of simulations, with 60 or more separate simulations for each imposed SST anomaly pattern, so that even weak atmospheric responses can be captured and analyzed.A further asset in identifying the atmospheric response to KOE-related SST variations is a simplified ocean model which allows the near-surface ocean to respond to changes in surface winds and other atmospheric forcing. The model is referred to as a "pencil" ocean model, or PenOM, because it represents the up and down transfer of heat in a column of the ocean below each grid box of the surface atmosphere. PenOM does not simulate the lateral movement of water in ocean currents, but work under this award adds the capability to represent changes in SST due to Ekman transport, meaning the sideways drift caused by the Coriolis force acting on water pushed along by the surface wind.The work is of societal as well as scientific interest due to its relevance to long-term weather prediction as noted above. Also, the PenOM configuration with Ekman transport will be made available to the worldwide research community through the Community Earth System Model as part of its suite of simpler model configurations. The work promotes international collaboration in atmospheric research through its collaboration with Dr. Arnaud Czaja at Imperial College London, through the arrangement noted below. Also, the project supports several outreach activities including the production of a short educational video featuring model simulations and research results. The project also provides support and training to a postdoctoral research associate.This project is jointly funded by the National Science Foundation’s Directorate of Geosciences (NSF/GEO) and the National Environment Research Council (NERC) of the United Kingdom (UK) via the NSF/GEO-NERC Lead Agency Agreement. The Agreement allows a single joint US/UK proposal to be submitted and peer-reviewed by the Agency whose investigator has the largest proportion of the budget. Upon successful joint determination of an award, each Agency funds the proportion of the budget and the investigators associated with its own country.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

北太平洋地区的冬季有无休止的额叶风暴游行，在日本附近形成，并在越过海洋到达北美时建造。即使固定海面温度（SST），模型模拟也可以产生逼真的北太平洋风暴，这表明风暴的存在归功于强大的上层喷气流并进行南北式大凹陷温度对比，而不是空中海上相互作用。然而，有一个有趣的暗示，即风暴行为可能会受到基础SST的变化的影响，并且有些迹象表明，缓慢变化的SST可能会以证明对做出长期天气预测有用的方式改变风暴路径和行为。由于蜿蜒曲折（KOE），这是一种狭窄的海洋电流，从日本海岸延伸到太平洋，因此发生了感兴趣的SST变化。 KOE是温暖的电流，当KOE向北或南方移动时，其电流和冷水之间的急剧对比会产生相对较强的SST变化。进行识别和分析与KOE相关的SST对暴风雨和大气循环的影响的影响。但是，首席研究人员（PIS）和其他人最近的工作表明，捕获大气反应的关键是要大幅度提高用于此目的的大气模型的分辨率。特别是，PI开发了社区大气模型6（VR-CAM6）的可变分辨率版本，该版本利用光谱元件动态核心来增加北太平洋的分辨率（从20N到60n到60n和130E到110W）。北太平洋以外的较低分辨率使该模型的运行水平足够便宜，可以允许大量的模拟组合，每种施加的SST异常模式具有60个或更多单独的模拟，以便甚至可以捕获和分析较弱的大气响应。在识别SST型号的大气响应中，可以使海洋模型的大气层变化，从而使大气响应逐渐变化。该模型被称为“铅笔”海洋模型，或者是阴茎，因为它代表了在表面大气的每个网格盒下方的海洋柱中的向上和向下传递。 Penom不会模拟洋流中水的横向移动，但是在该奖项下工作的工作增加了由于Ekman运输而代表SST的功能，这意味着由Coriolis力量沿着表面风推到水上的Coriolis力量引起的侧向驾驶。该工作具有社会和科学兴趣，因为它与上述长期天气预测相关。此外，作为其更简单的模型配置套件的一部分，将通过社区地球系统模型向全球研究社区提供带有Ekman Transport的PENOM配置。这项工作通过以下安排与伦敦帝国学院的Arnaud Czaja博士的合作来促进大气研究的国际合作。此外，该项目还支持几项外展活动，包括制作一个简短的教育视频，其中包含模型模拟和研究结果。该项目还为博士后研究助理提供了支持和培训。该项目由国家科学基金会的地球科学局（NSF/GEO）和英国国家环境研究委员会（NERC）共同资助，并通过NSF/GEO-GEO-NERC-NERC LEAD CREAD AGENAT。该协议允许该机构提交和同行评审的一项联合提案，其调查员的预算比例最大。成功确定裁决后，每个机构都资助了预算的比例和与其国家相关的调查人员的比例。该奖项反映了NSF的法定任务，并使用基金会的知识分子优点和更广泛的影响审查标准，被视为通过评估而被视为珍贵的支持。

项目成果

On the Statistical Estimation of Asymmetrical Relationship Between Two Climate Variables

• DOI: 10.1029/2022gl100777
• 发表时间: 2022-10-28
• 期刊: GEOPHYSICAL RESEARCH LETTERS
• 影响因子: 5.2
• 作者: Frankignoul, Claude;Kwon, Young-Oh
• 通讯作者: Kwon, Young-Oh

Multidecadal Regime Shifts in North Pacific Subtropical Mode Water Formation in a Coupled Atmosphere‐Ocean‐Sea Ice Model

耦合大气-海洋-海冰模型中北太平洋副热带模式水形成的多年代际变化

• DOI: 10.1029/2022gl099406
• 发表时间: 2022
• 期刊: Geophysical Research Letters
• 影响因子: 5.2
• 作者: Kim, Sang‐Yeob;Kwon, Young‐Oh;Park, Wonsun;Lee, Ho Jin
• 通讯作者: Lee, Ho Jin