Modelling the ocean circulation with random numbers

用随机数模拟海洋环流

• 批准号: NE/K013548/1
• 负责人: Laure Zanna
• 金额: $ 40.3万
• 依托单位: University of Oxford
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2014
• 资助国家: 英国
• 起止时间: 2014 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FK013548%2F1
• 关键词: Modelling; ocean; circulation; random; numbers

The ocean contains a vigorous geostrophic mesoscale eddy field with spatial scales of approximately 100km at mid-latitudes, evolving over time scales from weeks to months. These eddies are important in establishing the ocean's circulation and tracer distributions in the ocean' interior. In the vicinity of the Gulf Stream and the Kuroshio's extensions and in the Antarctic Circumpolar Current (ACC), eddies are the primary means by which heat is transported poleward. However, to adequately simulate the mesoscale eddy field and associated turbulent cascades of tracers in numerical models, horizontal resolution of at least 10 km is necessary. It is therefore unlikely that climate models will systematically resolve ocean eddies and their effect needs to be parametrized. Large improvements have been made in the implementation of deterministic parameterizations of mesoscale eddies. Despite such improvements, the major source of model error remains the imperfect or missing closure of these subgrid scale processes.In the current proposal, we aim to improve our knowledge of how ocean eddy variability influences the large-scale climate. We also aim to develop a novel stochastic closure as an alternative approach to the current deterministic parameterization. Such stochastic closure offers the advantage of an explicit representation of the inherent uncertainty associated the parametrized processes. The new stochastic parameterization of eddies will be tested on a state-of-the-art climate model and the impact on the mean climate, its variability and predictability will be investigated.

海洋包含一个强烈的地转中尺度涡旋场，其空间尺度在中纬度地区约为100公里，随时间尺度从几周到几个月不等。这些涡流对建立海洋环流和海洋内部示踪剂分布具有重要意义。在墨西哥湾流和黑潮延伸区附近以及南极环极流（ACC）中，涡旋是热量向极地输送的主要途径。然而，为了在数值模式中充分模拟中尺度涡旋场和相关的示踪剂湍流级联，至少需要10公里的水平分辨率。因此，气候模式不太可能系统地解决海洋涡旋，它们的影响需要参数化。在实现中尺度涡旋的确定性参数化方面已经有了很大的改进。尽管有这些改进，模型误差的主要来源仍然是这些子网格尺度过程的不完善或缺失闭合。在目前的建议中，我们的目标是提高我们对海洋涡旋变率如何影响大尺度气候的认识。我们还旨在开发一种新的随机闭包作为当前确定性参数化的替代方法。这种随机闭合提供了一个明确表示与参数化过程相关的固有不确定性的优势。新的涡旋随机参数化方法将在一个最先进的气候模式上进行测试，并将研究其对平均气候、其变率和可预测性的影响。

项目成果

The relationship between a deformation-based eddy parameterization and the LANS-a turbulence model

基于变形的涡流参数化与LANS-湍流模型之间的关系

• DOI: 10.1016/j.ocemod.2018.04.007
• 发表时间: 2018
• 期刊: Ocean Modelling
• 影响因子: 3.2
• 作者: Bachman S

Seasonal and decadal forecasts of Atlantic Sea surface temperatures using a linear inverse model

• DOI: 10.1007/s00382-016-3375-1
• 发表时间: 2017-09-01
• 期刊: CLIMATE DYNAMICS
• 影响因子: 4.6
• 作者: Huddart, Benjamin;Subramanian, Aneesh;Palmer, Tim
• 通讯作者: Palmer, Tim

Oceanic Stochastic Parameterizations in a Seasonal Forecast System

• DOI: 10.1175/mwr-d-15-0245.1
• 发表时间: 2015-06
• 期刊: Monthly Weather Review
• 影响因子: 3.2
• 作者: M. Andrejczuk;F. Cooper;S. Juricke;T. Palmer;A. Weisheimer;L. Zanna

The Impact of Horizontal Resolution on Energy Transfers in Global Ocean Models

水平分辨率对全球海洋模型中能量转移的影响

• DOI: 10.3390/fluids2030045
• 发表时间: 2017
• 期刊: Fluids
• 影响因子: 1.9
• 作者: Kjellsson J

A note on 'Toward a stochastic parameterization of ocean mesoscale eddies'

关于“海洋中尺度涡旋的随机参数化”的注释

• DOI: 10.1016/j.ocemod.2017.03.007
• 发表时间: 2017
• 期刊: Ocean Modelling
• 影响因子: 3.2
• 作者: Grooms I