Collaborative Research: Tropical waves and their effects on circulation from 3D GPS radio occultation sampling from stratospheric balloons in Strateole-2

合作研究：热带波及其对 Strateole-2 平流层气球 3D GPS 无线电掩星采样的环流影响

• 批准号: 1642650
• 负责人: Jennifer Haase
• 金额: $ 110.34万
• 依托单位: University of California-San Diego Scripps Inst of Oceanography
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-02-01 至 2025-01-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1642650&HistoricalAwards=false
• 关键词: Collaborative; Research; Tropical; waves; their

The tropical upper troposphere and lower stratosphere are home to a variety of wave motions which play key roles in weather, climate, and atmospheric circulation. Waves which are broad (horizontal wavelengths spanning several degrees latitude) but shallow (vertical wavelengths of about one to four kilometers), generated by large areas of tropical convection, are the subject of this investigation. These waves are of interest for three reasons: first, the waves can induce the formation of cirrus clouds in the tropical tropopause layer (TTL), the transition zone between the troposphere and stratosphere that extends from about 14km to 18.5km. TTL cirrus can form as rising air motions associated with the waves depress air temperatures and cause water vapor to freeze out as cirrus ice crystals. The resulting clouds may be too thin to see from the ground or from satellites, yet they have an important climatic effect as they trap outgoing infrared radiation and thus warm the atmosphere. The prevalence of such clouds is difficult to quantify, and the relative importance of wave motions as a source of TTL cirrus, in comparison to cirrus formation due to outflow of ice particles from deep cumulus clouds, is not known.Second, the freezing out of water vapor by wave-induced temperature depression could be an important constraint on the amount of water vapor entering the stratosphere. The TTL is sometimes referred to as the "gateway to the stratosphere", as most of the water vapor in the stratosphere over the entire globe enters through the TTL. The stratosphere is extremely dry compared to the troposphere, but stratospheric water vapor is nevertheless important as it has a relatively strong greenhouse effect and can lead to the formation of the polar stratospheric clouds which are key to the formation of the ozone hole.Third, waves can transport momentum from the troposphere to the stratosphere, and wave momentum transport is the primary driver of the stratospheric Quasi-Biennial Oscillation (QBO), an alternation between easterly and westerly winds occurring over the global tropics with a cycling time in excess of two years. While the QBO is narrowly confined to the low-latitude stratosphere, it can influence weather and climate worldwide through its effects on prominent modes of climate variability such as the North Atlantic Oscillation. While the theory of wave momentum transport is well established, uncertainties remain as to the relative importance of different wave types in driving the QBO, and current weather and climate models have difficulty in simulating it.This project seeks to improve understanding of waves in the TTL by building and launching a balloon-borne instrument which receives positioning signals from satellites of the Global Navigation Satellite System (GNSS, which includes the GPS satellites launched by the US). The GNSS signals are refracted as they pass through the atmosphere, and the amount of refraction can be used to infer air temperature in the upper troposphere. Because the profiles are retrieved from the rising and setting, or occultation, of the GNSS satellites relative to the receiver, the balloon-borne instrument has the acronym ROC, for Radio OCcultation.ROC is developed for use on balloons flow as part of the Strateole-2 field campaign organized by the Centre National d'Etudes Spatiales (CNES), the French Space Agency, and the Laboratoire de Meteorologie Dynamic (LMD) of the University of Paris-Saclay. Strateole-2 is a five-year campaign, with a small validation deployment in 2018 and full science deployments in 2020-2021 and 2022-2023. Balloons are launched from the Seychelles (about 5S in the Indian Ocean), with the expectation that each balloon will circle the earth for up to 90 days and observe the TTL between 20S and 15N. This award supports US participation in the validation campaign and the first full science deployment, along with post-campaign analysis. It is one of three awards made to US PIs for participation in Strateole-2, the full set being AGS-1643022, AGS-1642277/1642246, and AGS-1642650/1653644. ROC is oriented to retrieve signals from GNSS satellites on either side of the balloon flight path, with observations taken between 8km and the flight level of about 20km and a vertical resolution between 200m and 250m. The observing geometry is such that observations at lower levels are farther away from the balloon, so that observations at 18, 15, and 12km altitude correspond to distances of roughly 100, 200, and 300km on either side of the balloon. The waves of interest have periods from hours to days and ROC can record two to three occultations per hour. Thus the three-dimensional structure of the waves is captured by the ROC measurements as the balloon advances along its trajectory.ROC is accompanied by two other instruments which provide complementary observations. One is the Balloonborne Cloud Overshoot Observation Lidar (BeCOOL), provided by the Laboratoire Atmospheres, Milieux, Observations Spatiales (LATMOS, a laboratory of the Institut Pierre Simon Laplace) in collaboration with CNES. The lidar provides measurements of cirrus clouds which can be combined with ROC observations to examine the role of wave motions in generating cirrus clouds. The other is the Temperature SENsor (TSEN), an instrument from LMD which records atmospheric temperature and pressure at the gondola. Gondola displacements are precisely determined by ROC, and TSEN observations are used to factor out gondola movement relative to the ambient wave motion (these are super-pressure balloons which fly at a level of constant density). The displacement data are then used to estimate the wave momentum flux at flight level associated with the large-scale waves observed by ROC.The work has scientific broader impacts due to the value of the observations for addressing a variety of questions regarding the effect of wave motions on TTL clouds, stratospheric humidity, and the QBO. Observations collected in this project will be made available to the research community from servers at the Laboratory for Atmospheric and Space Physics at the University of Colorado so that they can be freely examined by the research community. The project also engages undergraduate students through a research class, offered simultaneously at the University of California San Diego, the University of Arizona (UA), and the Autonomous University of Mexico (UNAM), in which students design a research project based on a test flight of ROC. The class is followed by undergraduate research internships at UCSD, UA, the Research Experiences in Solid Earth Sciences for Students (RESESS) program at UNAVCO (the University NAVSTAR Consortium, dedicated to applying GNSS technology to earth science), and the Significant Opportunities in Atmospheric Research and Science (SOARS) program of the University Corporation for Atmospheric Research. Beyond these broader impacts, the project supports two graduate students.

热带对流层和下层平流层是各种波动运动的家园，这些波动在天气，气候和大气循环中起着关键作用。 这项研究的主题是宽阔的波（水平波长，横跨纬度几个度），但浅（由大面积的热带对流面积产生的垂直波长约为一到四公里）是这项研究的主题。 这些波是有三个原因而引起的：首先，这些波可以诱导热带对流层层层（TTL）中的卷云的形成，这是对流层和平流层之间从约14公里至18.5公里延伸的过渡区。 TTL卷轴可以形成与波浪降低空气温度相关的空气运动的上升，并导致水蒸气冻结为卷心冰晶体。 所产生的云可能太薄，无法从地面或卫星上看到，但是当它们捕获向外发出的红外辐射并因此温暖大气时，它们具有重要的气候效应。 这种云的流行率很难量化，并且波动作为TTL卷轴的来源的相对重要性与卷轴形成相比，由于冰颗粒从深云云中流出而导致的卷心cirrus形成，尚不清楚，尚不清楚，冻结在波浪诱发的温度下，冻结了水蒸气的冻结可能是对水vapor的重要约束。 TTL有时被称为“通往平流层的门户”，因为整个世界上平流层中的大多数水蒸气都通过TTL进入。 The stratosphere is extremely dry compared to the troposphere, but stratospheric water vapor is nevertheless important as it has a relatively strong greenhouse effect and can lead to the formation of the polar stratospheric clouds which are key to the formation of the ozone hole.Third, waves can transport momentum from the troposphere to the stratosphere, and wave momentum transport is the primary driver of the stratospheric Quasi-Biennial Oscillation (QBO),在全球热带地区发生的东风和西风之间的交替，骑自行车时间超过两年。尽管QBO狭窄地局限于低纬度平流层，但它可以通过其对北大西洋振荡等气候变化的突出模式的影响来影响全世界的天气和气候。 尽管波动动量传输的理论已经良好，但不确定性仍然存在着不同波动类型在驱动QBO中的相对重要性，当前的天气和气候模型在模拟它方面都很困难。该项目旨在通过构建和启动启动的气球仪器（包括从全球导航卫星中的卫星上定位信号）来提高对TTL的了解的理解（ 我们）。 GNSS信号在通过大气时会折射，并且折射率可用于推断对流层上部的空气温度。 Because the profiles are retrieved from the rising and setting, or occultation, of the GNSS satellites relative to the receiver, the balloon-borne instrument has the acronym ROC, for Radio OCcultation.ROC is developed for use on balloons flow as part of the Strateole-2 field campaign organized by the Centre National d'Etudes Spatiales (CNES), the French Space Agency, and the Laboratoire de Meteorologie Dynamic (LMD) of巴黎 - 萨克莱大学。 Strateo-2是一项为期五年的运动，在2018年进行了少量验证部署，并在2020 - 2021年和2022 - 2023年进行了全面的科学部署。气球是从塞舌尔（Sehehelles）发射的（印度洋约5秒），期望每个气球会绕地球旋转长达90天，并观察到20年代至15N之间的TTL。该奖项支持我们参与验证活动和第一个完整的科学部署以及挑战后分析。它是为美国PIS颁发的三个奖项之一，全套为AGS-1643022，AGS-1642277/1642246和AGS-1642650/1653644。将ROC定向以从气球飞行路径两侧的GNSS卫星中检索信号，观测值在8公里至20公里的飞行水平之间，并且在200m至250m之间的垂直分辨率。观察几何形状使得较低水平的观测值离气球较远，因此在气球两侧的18、15和12公里高度的观测值对应于大约100、200和300公里的距离。 感兴趣的浪潮从几个小时到几天都有时间，而ROC可以每小时记录两到三个掩体。 因此，随着气球沿其轨迹的前进，ROC测量值捕获了波浪的三维结构。ROC伴随着另外两种提供互补观测的仪器。 一个是由Laboratoire氛围，Milieux，Pieratiales（Latmos，Latmos，Pierre Pierre Simon Laplace的实验室）与CNES合作提供的Balloonborn云过冲观测LIDAR（BECOOL）。 LIDAR提供了卷云的测量值，可以将其与ROC观测值结合使用，以检查波运动在产生卷云中的作用。 另一个是温度传感器（TSEN），一种来自LMD的仪器，记录了缆车的大气温度和压力。 缆车位移是通过ROC精确确定的，TSEN观察值用于将相对于环境波运动的缆车移动（这些是超压气球，它们以恒定密度的水平飞行）。 然后，将位移数据用于估计与ROC观察到的大规模波相关的飞行水平的波动动量通量。由于观测值的价值解决了有关波动对TTL云的影响的各种问题的价值，这项工作具有更广泛的影响。 该项目中收集的观察结果将从科罗拉多大学大气与太空物理实验室的服务器提供给研究社区，以便研究界可以自由检查。该项目还通过研究课程与本科生互动，并在加利福尼亚大学圣地亚哥分校，亚利桑那大学（UA）和墨西哥自主大学（UNAM）提供了同时提供的研究课程，该大学的学生在其中根据ROC的测试飞行设计了研究项目。 该课程之后是UA，UA的本科研究实习，在UNAVCO（大学NAVSTAR财团，专门用于地球科学上的GNSS技术）的学生（Resess）计划的固体地球科学（Resess）计划以及大气研究和科学的大气研究计划中的重要机会。除了这些更广泛的影响之外，该项目还支持两名研究生。

项目成果

Equatorial waves resolved by balloon-borne Global Navigation Satellite System radio occultation in the Strateole-2 campaign

• DOI: 10.5194/acp-22-15379-2022
• 发表时间: 2022-12
• 期刊: Atmospheric Chemistry and Physics
• 影响因子: 6.3
• 作者: B. Cao;J. Haase;M. Murphy;M. Alexander;M. Bramberger;A. Hertzog

Around the World in 84 Days

• DOI: 10.1029/2018eo091907
• 发表时间: 2018-03
• 期刊: Eos
• 作者: J. Haase;M. Alexander;A. Hertzog;L. Kalnajs;T. Deshler;S. Davis;R. Plougonven;P. Cocquerez;Stéphanie Venel

Optimizing Simultaneous Water Level and Wave Measurements From Multi‐GNSS Interferometric Reflectometry Over 1 Year at an Exposed Coastal Site

在暴露的沿海地点优化多GNSS干涉反射仪的同步水位和波浪测量一年多

• DOI: 10.1029/2022ea002767
• 发表时间: 2023
• 期刊: Earth and Space Science
• 影响因子: 3.1
• 作者: Sepúlveda, Ignacio;Cao, Bing;Haase, Jennifer S.;Murphy, Michael J.
• 通讯作者: Murphy, Michael J.