SODA4: ocean climate variability at mesoscale resolution

SODA4：中尺度分辨率的海洋气候变化

基本信息

批准号：
1948952
负责人：
James Carton
金额：
$ 96.05万
依托单位：
University of Maryland, College Park
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2020
资助国家：
美国
起止时间：
2020-03-15 至 2024-02-29
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1948952&HistoricalAwards=false
关键词：
SODA4 ocean climate variability mesoscale

项目摘要

Oceanographic observations are sparse and not uniformly distributed over space or time. Since many analyses benefit from complete fields available over a regular grid, reanalysis products have been developed to fill this gap by constraining a numerical model with available observations. One of the most widely used ocean reanalysis products is the Simple Ocean Data Assimilation. Its current version (SODA3) does not have sufficient resolution to capture most of the eddies, especially in the high latitude regions. This may cause biases in regions where strong eddy activity or wind forcing and mixing are present. This project exploits the growth of computational power to make improved use of the limited historical observational record using a model that resolves the dominant smaller scales of motion in order to produce a mesoscale resolving global ocean/sea ice reanalysis called SODA4. The project also includes a focused examination of the role of mesoscale processes in the Arctic and in subpolar/Arctic exchanges. This work is directed toward understanding the role the ocean and sea ice systems play in regulating and modifying Earth’s weather and climate partly as a guide to improve forecasts of future changes. Improved understanding of historical ocean variability benefits the scientific enterprise by playing a crucial role as a guide to improve forecasts of coupled climate variability and by adding additional value to the historical observational record by reconstructing their basin-scale context. By supporting development and distribution of more realistic historical climate reanalysis spanning the past four decades this project can serve to integrate research activities across multiple areas and disciplines. The improved representation of smaller scales of motion and of regions of high human impact such as the nearshore environment should also help inform a broad community (coastal planners and engineers, wind farms, the fisheries community, etc.) regarding historical ocean variability and change. This research project also serves educational mission of University of Maryland College Park in several ways. Most directly it will support the dissertation research of a graduate student at the Department of Atmospheric and Oceanic Science. It will also involve a number of undergraduate research projects.Examination of SODA3 results shows that its resolution is insufficient where mesoscale variability and near-surface diapycnic processes play dominant roles. This project explores the additional improvements to representation of the state of the ocean/sea ice system that can be gained by more completely representing oceanic mesoscale processes even during decades when mesoscale-resolving observing systems were not available. One region which will benefit from enhanced resolution is the Arctic Ocean and its connection to the subpolar gyres. The subpolar North Atlantic is the major route by which water is exchanged with the Arctic Ocean and this connection is of particular interest for many reasons. First, the surface water of the Nordic Seas is warming rapidly and the winter ice is retreating. Second, strong decadal temperature variability is present with unknown consequences for the central Arctic. Third it is a key region of deepwater formation. This project thus includes a focused effort to improve representation and diagnosis of the dynamics of subpolar/Arctic exchanges and their connection to variable Arctic Ocean water masses.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.

海洋学观察稀疏，在空间或时间上不均匀分布。由于与常规网格相比，许多分析从可用的完整字段中受益，因此已经开发了重新分析产品来填补这一空白，并以可用的观测值来限制数值模型。使用最广泛的海洋重新分析产品之一是简单的海洋数据同化。其当前版本（SODA3）没有足够的分辨率来捕获大多数涡流，尤其是在高纬度地区。这可能会导致呈现强大的涡流或风力强迫和混合的区域。该项目利用了计算能力的增长，以改善使用有限的历史观察记录的使用，该模型可以解决主要的较小运动尺度，以产生中尺度，以解决称为SODA4的全球海洋/海冰重新分析。该项目还包括对中尺度过程在北极和亚极/北极交换中的作用的重点检查。这项工作旨在了解海洋和海冰系统在调节中的作用，并改变地球的天气和气候，部分是改善未来变化森林的指南。对历史海洋可变性的了解得以提高，通过在改善耦合气候变异性森林的指南中发挥关键作用，并通过重建其盆地规模的环境来为历史观察记录增添更多价值，从而使科学企业受益匪浅。通过支持过去四十年的更现实的历史气候重新分析的开发和分布，该项目可以将研究活动整合到多个领域和学科之间。较小的运动规模和高度人类影响区域（例如近岸环境）的改善也应有助于告知广泛的社区（沿海规划师和工程师，风电场，渔业社区等），涉及历史的海洋变异性和变化。该研究项目还以多种方式服务于马里兰大学公园的教育任务。最直接的是，它将支持大气与海洋科学系研究生的论文研究。它还将涉及许多本科研究项目。苏打研究结果表明，其分辨率不足，而中尺度的可变性和近乎表面的Diapycnic过程起着主要作用。该项目探讨了代表海洋/海冰系统状态的其他改进，即使在几十年中，在中尺度上分析的观察系统也无法完全代表海洋中的中尺度过程。一个将从增强分辨率中受益的区域是北极海洋及其与亚极分子的联系。北大西洋次极是通过北极海洋变化的主要途径，由于许多原因，这种联系特别令人感兴趣。首先，北欧海洋的地表水正在迅速变暖，冬季冰正在撤退。其次，强烈的衰老温度变异性呈现出对中央北极的不明后果。第三是深水形成的关键区域。因此，该项目包括一项重点努力，以改善亚极/北极交易所动态的表示和诊断，以及它们与可变的北极海水质量的联系。这项奖项反映了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来通过评估来诚实地支持。