Studies of the Maritime Atmospheric Boundary Layer during DYNAMO

DYNAMO 期间海洋大气边界层的研究

• 批准号: 1853633
• 负责人: Richard Johnson
• 金额: $ 62.66万
• 依托单位: Colorado State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2023-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1853633&HistoricalAwards=false
• 关键词: Studies; Maritime; Atmospheric; Boundary; Layer

The atmospheric boundary layer (ABL), typically the lowest kilometer or two of the atmosphere, has an outsized influence on the development of deep convective clouds over the tropical oceans. The role of the ABL in the development of the Madden-Julian Oscillation (MJO), a large eastward moving region of convection that forms over the Indian Ocean, was a primary focus of the 2011 Dynamics of the MJO (DYNAMO) field campaign (see for example awards 1022899 and 1059899). The campaign collected observations from four island stations and two ship stations in the Central Indian Ocean. Work under this award uses the DYNAMO observations to characterize the behavior of the tropical marine ABL and its interactions with the underlying ocean. It also seeks to determine the extent to which observations taken from the island stations are influenced by island effects which do not represent the conditions over the surrounding ocean that matter for the development of widespread convection.ABL properties to be examined include temperature, moisture, stability, winds, and cloudiness, with a particular focus on the diurnal cycle of ABL depth. The diurnal cycle is assessed from weather balloons launches that took place every three hours during the intensive observing period of the campaign. The PI has developed a method to determine the height of the ABL from the signal-to-noise ratio of continuous observations from the wind profiler and Radio Acoustic Sounding System (RASS) deployed on the islands and ships. The technique could prove useful for filling in the gaps between balloon launches and verifying that the balloon observations capture the full diurnal cycle of ABL depth. Profiler and RASS data collected on the island of Diego Garcia and the research vessel Revelle, at the same latitude and separated by 10 degrees longitude, are compared to detect island effects. Two of the islands used for the campaign are atolls (the second is Gan Island in the Maldives), which have minimal land area but surround lagoons with a relatively strong diurnal temperature cycle which might influence ABL observations. Observations taken from the Revelle and moorings deployed from the ship are used to characterize air-sea interactions relevant to ABL development and subsequent convection.The work has societal value due to the many ways in which the MJO affects weather and climate worldwide, including the development of hurricanes in the Gulf of Mexico and extreme rainfall events in California. The MJO presents a challenge to current weather prediction models, and work performed here may lead to improved forecasts of the MJO and its impacts. More specifically, the project generates forcing datasets that can be used for model development. Products generated under this award are made openly available to the research and operational communities through a website at the National Center for Atmospheric Research.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.

大气边界层（ABL），通常是最低公里或两个大气的大气层，对热带海洋上深云的发展产生了巨大影响。 ABL在Madden-julian振荡（MJO）的发展中的作用是印度洋上形成的大型向对流区域，是2011年MJO（Dynamo）现场运动动态的主要重点（例如，请参阅奖项10222899和1059899）。 该运动从印度洋中部的四个岛屿站和两个船舶站收集了观察结果。 该奖项下的工作利用发电机观察来表征热带海洋ABL的行为及其与基础海洋的相互作用。 它还试图确定从岛屿站的观察结果受岛影响的影响程度，而岛屿效应并不代表周围海洋的条件，这对于开发广泛的对流而言至关重要。要检查的ABL属性的特性包括温度，水分，水分，稳定性，风能和云彩，特别关注ABL深度的局限性周期。 昼夜周期是根据在竞选活动的密集观察期间每三个小时进行一次的气候气球发射的评估。 PI开发了一种方法来确定ABL的高度，从岛屿和船只上部署的风剖面和无线电声音系统（RASS）的连续观测值的信噪比。 该技术可能对填补气球发射之间的空白并验证气球观测结果捕获ABL深度的完整昼夜周期很有用。 比较了在迭戈·加西亚岛（Diego Garcia）和研究容器狂欢的纬度，并在同一纬度上收集的剖面数据和经度分开，以检测岛屿效应。 用于活动的两个岛屿是Atolls（第二个是马尔代夫的Gan Island），它们的土地面积最小，但围绕着具有相对较强的昼夜温度周期的泻湖，这可能会影响ABL的观察。 从雷维勒（Revelle）和从船上部署的系泊开始的观察结果用于表征与ABL开发和随后的对流相关的空气相互作用。由于MJO在全球范围内影响天气和气候的多种方式，这项工作具有社会价值，包括墨西哥湾和墨西哥湾的飓风发展，包括墨西哥湾和加利福尼亚州的极端降雨事件。 MJO对当前天气预测模型提出了挑战，此处执行的工作可能会改善对MJO的预测及其影响。 更具体地说，该项目会生成可用于模型开发的强迫数据集。 根据该奖项生成的产品通过国家大气研究中心的网站公开向研究和运营社区公开提供。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，认为值得通过评估值得支持。

项目成果

Comparison of Conventional and Constrained Variational Methods for Computing Large‐Scale Budgets and Forcing Fields

计算大规模预算和强制场的传统方法和约束变分方法的比较

• DOI: 10.1029/2021jd035183
• 发表时间: 2021
• 期刊: Journal of Geophysical Research: Atmospheres
• 作者: Ciesielski, Paul E.;Johnson, Richard H.;Tang, Shuaiqi;Zhang, Yunyan;Xie, Shaocheng
• 通讯作者: Xie, Shaocheng

The Atmospheric Boundary Layer and the Initiation of the MJO

大气边界层和 MJO 的启动

• DOI: 10.1175/jcli-d-23-0210.1
• 发表时间: 2023
• 期刊: Journal of Climate
• 影响因子: 4.9
• 作者: Johnson, Richard H.;de Szoeke, Simon P.;Ciesielski, Paul E.;Brewer, W. Alan
• 通讯作者: Brewer, W. Alan

Potential Vorticity Generation by West African Squall Lines

西非飑线产生的潜在涡量

• DOI: 10.1175/mwr-d-19-0342.1
• 发表时间: 2020
• 期刊: Monthly Weather Review
• 影响因子: 3.2
• 作者: Johnson, Richard H.;Ciesielski, Paul E.
• 通讯作者: Ciesielski, Paul E.

Hydrometeor Storage and Advection Effects in DYNAMO Budget Analyses

DYNAMO 预算分析中的水凝物储存和平流效应

• DOI: 10.1175/jas-d-21-0266.1
• 发表时间: 2022
• 期刊: Journal of the Atmospheric Sciences
• 影响因子: 3.1
• 作者: Johnson, Richard H.;Ciesielski, Paul E.;Schubert, Wayne H.
• 通讯作者: Schubert, Wayne H.

Small Island Effects in DYNAMO and Their Impact on Large-Scale Budget Analyses

DYNAMO 中的小岛效应及其对大规模预算分析的影响

• DOI: 10.1175/jamc-d-20-0238.1
• 发表时间: 2021
• 期刊: Journal of Applied Meteorology and Climatology
• 影响因子: 3
• 作者: Ciesielski, Paul E.;Johnson, Richard H.
• 通讯作者: Johnson, Richard H.