The South Georgia Wave Experiment (SG-WEX)

南乔治亚波浪实验（SG-WEX）

• 批准号: NE/K012584/1
• 负责人: Andrew Ross
• 金额: $ 37.37万
• 依托单位: University of Leeds
• 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%2FK012584%2F1
• 关键词: South; Georgia; Wave; Experiment; SG

Gravity waves are an important type of atmospheric wave. They play a key role in many atmospheric processes, ranging from convection to the mixing of chemical species to influencing the global-scale circulation of the stratosphere and mesosphere. Because of this, it is essential to represent their effects in numerical weather prediction and climate models.Gravity waves are generated by sources including winds blowing over mountains, jet-stream instabilities and strong convection. The waves can transport energy and momentum away from these sources and deposit them at greater heights, thus exerting a significant "drag" on the circulation and so coupling together different layers of the atmosphere. Recent studies have shown that isolated mountainous islands in regions of strong winds can be intense sources of gravity waves that can have climatologically-significant effects on atmospheric circulation. However, most climate and numerical weather prediction models cannot accurately model waves from such small, intense island sources because the islands are too small compared to the resolution of the models - this is the "small island problem". Here, we propose a major coordinated observational and modelling experiment to determine the nature and impacts of gravity waves generated by the most important of all these islands, South Georgia in the Southern Atlantic. Our experiment will answer the following questions:1. What is the nature of gravity waves generated by South Georgia and what is their variability?2. What is the contribution of these gravity waves to the total field of gravity waves over the South Atlantic?3. What is the influence of gravity waves from South Georgia on the mesosphere?4. How can these observations be used to improve gravity-wave parametrizations in models?5. How important is South Georgia in comparison to other gravity-wave sources and how does it impact local winds and the development of synoptic systems?To answer these questions we will make measurements of gravity waves over and around South Georgia in two radiosondes campaigns in which meteorological balloons will be launched from South Georgia. We will place these observations in context with measurements made by satellite across the whole South Atlantic. Significantly, we will also deploy the first atmospheric radar on South Georgia. This is a meteor radar that will make the first ever measurements of gravity waves (and winds, tides and large-scale planetary waves) in the mesosphere over South Georgia at heights of 80 - 100 km.These experimental results will be complemented by a programme of modelling work that will explore the propagation of gravity waves away from their sources. The observations will be used to help guide the development of new, improved, mathematical representations of gravity waves (so-called "parametrizations") allowing such islands to be better represented in the Met Office's Unified Model used for numerical weather prediction and climate studies. Finally, modelling studies will integrate these studies and determine the relative importance of South Georgia compared to other waves sources and investigate the impact ofGravity waves from South Georgia on local winds and the development of synoptic (weather) systems.

重力波是大气波的重要类型。它们在许多大气过程中起着关键作用，从对流到化学物种的混合，再到影响平流层和中层的全球尺度循环。因此，必须在数值天气预测和气候模型中代表它们的影响。重力波是由吹山，喷气流不稳定性和强烈对流的风的来源产生的。波浪可以将能量和动量从这些来源传递出来，并将其沉积在更大的高度上，从而在循环上施加了重要的“阻力”，从而将不同的大气层耦合在一起。最近的研究表明，在强风中，孤立的山区岛可以是强烈的重力波来源，这些引力波可能对气候对大气循环产生重要影响。但是，大多数气候和数值天气预测模型无法准确地对如此小的，强烈的岛屿来源的波浪进行建模，因为这些岛屿与模型的分辨率相比太小 - 这是“小岛问题”。在这里，我们提出了一个主要的协调观察和建模实验，以确定由所有这些岛屿，南乔治亚州南部大西洋南部最重要的重力波的性质和影响。我们的实验将回答以下问题：1。南佐治亚州产生的重力波的性质是什么，它们的变异性是什么？2。这些重力波对南大西洋上的重力波总场的贡献是什么？3。来自佐治亚州南部的重力波对中层的影响是什么？4。如何使用这些观察结果来改善模型中的重力波参数化？5。与其他重力波源相比，南佐治亚州有多重要，它如何影响当地风和天气系统的发展？回答这些问题，我们将在佐治亚州南部及其周围的重力波中进行两次辐射运动，其中将在两次辐射运动中发动气象气球，从而从南乔治亚乔治亚开始发射气象气球。我们将通过卫星在整个南大西洋进行的卫星进行测量，将这些观察结果放在上下文中。值得注意的是，我们还将在乔治亚州南部部署第一个大气雷达。这是一个流星雷达，它将在乔治亚州南部的Mesophere中以80-100 k的高度进行重力波（以及风，潮汐和大规模行星波）的第一个测量。这些实验结果将由建模工作的计划进行补充，这些计划将探索远离坟墓波的传播。该观察结果将用于帮助指导重力波的新，改进，数学表示的发展（所谓的“参数化”），从而使此类岛屿可以更好地在MET办公室用于数值天气预测和气候研究的统一模型中得到更好的代表。最后，与其他波源相比，建模研究将整合这些研究，并确定佐治亚州南部的相对重要性，并研究佐治亚州南部地区对当地风和概要（天气）系统发展的严重波的影响。

项目成果

Stratospheric gravity waves over the mountainous island of South Georgia: testing a high-resolution dynamical model with 3-D satellite observations and radiosondes

• DOI: 10.5194/acp-21-7695-2021
• 发表时间: 2021-05
• 期刊: Atmospheric Chemistry and Physics
• 影响因子: 6.3
• 作者: N. Hindley;C. Wright;A. Gadian;L. Hoffmann;J. Hughes;D. Jackson;J. King;N. Mitchell;T. Moffat‐Griffin;A. Moss;S. Vosper;A. Ross

Sampling Errors in Observed Gravity Wave Momentum Fluxes from Vertical and Tilted Profiles

垂直和倾斜剖面观测到的重力波动量通量的采样误差

• DOI: 10.3390/atmos11010057
• 发表时间: 2020
• 期刊: Atmosphere
• 影响因子: 2.9
• 作者: Vosper S

The South Georgia Wave Experiment ( SG-WEX ): radiosonde observations of gravity waves in the lower stratosphere. Part I: Energy density, momentum flux and wave propagation direction

南乔治亚波实验（SG-WEX）：无线电探空仪观测平流层下部的重力波。

• DOI: 10.1002/qj.3181
• 发表时间: 2017
• 期刊: Quarterly Journal of the Royal Meteorological Society
• 影响因子: 8.9
• 作者: Moffat-Griffin T

The South Georgia Wave Experiment: A Means for Improved Analysis of Gravity Waves and Low-Level Wind Impacts Generated from Mountainous Islands

南乔治亚波浪实验：改进对山区岛屿产生的重力波和低层风影响的分析方法

• DOI: 10.1175/bams-d-16-0151.1
• 发表时间: 2018
• 期刊: Bulletin of the American Meteorological Society
• 影响因子: 8
• 作者: Jackson D

Radar observations of winds, waves and tides in the mesosphere and lower thermosphere over South Georgia island (54° S, 36° W) and comparison with WACCM simulations

南乔治亚岛（南纬 54°，西经 36°）上空中层和低热层风、波浪和潮汐的雷达观测并与 WACCM 模拟进行比较

• DOI: 10.5194/acp-22-9435-2022
• 发表时间: 2022
• 期刊: Atmospheric Chemistry and Physics
• 影响因子: 6.3
• 作者: Hindley N