Atmospheric Sounding Network in the Dynamics of the Madden-Julian Oscillation Project (DYNAMO)

马登-朱利安振荡项目 (DYNAMO) 动力学中的大气探测网络

• 批准号: 1059899
• 负责人: Richard Johnson
• 金额: $ 65.54万
• 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: 2011
• 资助国家: 美国
• 起止时间: 2011-04-01 至 2015-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1059899&HistoricalAwards=false
• 关键词: Atmospheric; Sounding; Network; Dynamics; Madden

The Dynamics of the Madden-Julian Oscillation (DYNAMO) field campaign is the US component of an international experiment in late 2011/early 2012 in the Indian Ocean, the Cooperative Indian Ocean Experiment on Intraseasonal Variability (CINDY2011). The overarching goal of DYNAMO is to expedite understanding of processes key to MJO initiation over the Indian Ocean and to improve simulation and prediction of the MJO. The field campaign will include multiple radars, atmospheric sounding sites, a research aircraft, multiple research vessels, and oceanic measurements. The three main hypotheses of DYNAMO are: 1) Deep convection can be organized into an MJO convective envelope only when the moist layer has become sufficiently deep over a region of the MJO scale; the pace at which this moistening occurs determines the duration of the pre-onset state, 2) Specific convective populations at different stages are essential to MJO initiation, and 3) The barrier layer, wind- and shear-driven mixing, shallow thermocline, and mixing-layer entrainment all play essential roles in MJO initiation in the Indian Ocean by controlling the upper-ocean heat content and SST, and thereby surface flux feedbackThis award is for planning and implementation of the sounding network for DYNAMO, as well as follow up quality control and analysis. The DYNAMO sounding network will consist of four locations: Gan, Diego Garcia, and two research vessels. The researchers will plan the sounding network for DYNAMO and establish a sounding data monitoring system which will be used for field quality control of the data and preparation of quick-look products. After the campaign, the team will prepare large-scale forcing fields for the DYNAMO modeling community, as well as conduct diagnostic studies involving the divergence and diabatic heating profiles and the boundary layer evolution through the life cycle of the MJO. These tasks will help to address Hypotheses 1 and 2 of the DYNAMO campaign. In addition to the overarching DYNAMO hypotheses, the researchers have identified two others that they plan to test: 1) The pre-onset (moistening or pre-conditioning) phase of the MJO over the Indian Ocean, rather than exhibiting a gradual, steady build-up of moisture in the lower troposphere, is characterized by a stepwise evolution of the moisture field, which is related to the development of distinct cloud populations, and 2) The mixed-layer depth and its properties over the central Indian Ocean vary on the timescale of the MJO and these variations have corresponding relationships to the evolving cloud and precipitation fields observed during DYNAMO.The broader impacts of the research include the involvement of multiple graduate students in the field campaign and data analysis. A successful DYNAMO campaign would lead to improved understanding of tropical convection, the predictability of the MJO, and downstream effects of the MJO on weather in the United States and other areas.

Madden-Julian Oscillation（MSTO）现场活动的动力学是2011年底/2012年初在印度洋进行的国际实验的美国组成部分，该实验是印度洋季节内变率合作实验（CINDY 2011）。 该项目的总体目标是加快对印度洋MJO启动的关键过程的理解，并改进MJO的模拟和预测。 实地活动将包括多个雷达、大气探测站、一架研究飞机、多艘研究船和海洋测量。 MJO的三个主要假设是：（1）只有当湿层在MJO尺度上变得足够深时，深对流才能组织成MJO对流包层;这种润湿发生的速度决定了预开始状态的持续时间，2）不同阶段的特定对流群体对于MJO的开始是必要的，和3）阻挡层，风和剪切驱动的混合、浅温跃层和混合层卷吸都通过控制上层海洋热含量和SST，从而控制表面通量反馈，在印度洋MJO的启动中发挥重要作用。该奖项用于规划和实施MJO探测网络，以及后续质量控制和分析。 该海洋探测网将由四个地点组成：甘、迭戈·加西亚和两艘研究船。 研究人员将为南极海洋观测组织规划探测网络，并建立一个探测数据监测系统，用于数据的现场质量控制和快速查看产品的准备。 活动结束后，该团队将为MJO建模社区准备大规模强迫场，并进行诊断研究，包括发散和非绝热加热剖面以及MJO生命周期中的边界层演变。 这些任务将有助于解决反腐败运动的假设1和假设2。 除了首要的假设之外，研究人员还确定了他们计划测试的另外两个假设：（1）发病前印度洋上空MJO的增湿或预调节阶段，而不是在对流层低层中表现出逐渐稳定的水分积累，其特征在于水分场的逐步演变，这与不同云群的发展有关，和2）混合层的深度和它的属性在印度洋中部的时间尺度上的MJO和这些变化有相应的关系，不断变化的云和降水场观测到的MJO。更广泛的影响的研究包括多个研究生参与的现场活动和数据分析。 一个成功的MJO活动将导致更好地了解热带对流，MJO的可预测性，以及MJO对美国和其他地区天气的下游影响。