Convective Precipitation and Heating Structures Observed by the SMART-Radar During the Dynamics of the Madden-Julian Oscillation Project (DYNAMO)

马登-朱利安振荡动力学(发电机)实地活动是2011年底/2012年初在印度洋进行的一项国际实验--印度洋季节内变化合作实验(CINDY2011)--的美国组成部分。迪纳摩的首要目标是加快对印度洋上启动MJO的关键过程的了解，并改进对MJO的模拟和预测。现场活动将包括多个雷达、大气探测点、一架研究机、多艘研究船和海洋测量。迪纳摩的三个主要假设是：1)只有当湿层在MJO尺度的区域变得足够深时，才能将深层对流组织成MJO对流包层；这种增湿发生的速度决定了预增湿状态的持续时间，2)不同阶段的特定对流种群对MJO的启动至关重要，3)障碍层、风和切变驱动的混合、浅层温跃层和混合层夹带都通过控制上层海洋热含量和海温，从而对表层通量反馈在印度洋MJO启动中发挥关键作用。该雷达将提供对降水对流的反射率和径向速度的连续测量，并作为迪纳摩的“主力”雷达，使其他雷达在扫描策略上有更大的灵活性。研究小组还将开发基线产品，以评估降水云的特性及其组织，包括：反射率PDF高度、回波顶部高度、对流-层状分类、雨图和雨/雪水分估计。还将编制根据径向速度和反射率测量计算的散度和潜热分布，并用于确定降水对流中低层和高层加热之间的平衡。这项工作的更广泛影响包括大量学生参与实地观察和数据分析，可能在阿杜环礁上开展的外联活动，以及加强国际合作。一个成功的迪纳摩运动将导致对热带对流、MJO的可预测性以及MJO对美国和其他地区天气的下游影响的了解。

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 feedbackIn this award, the investigator will deploy a SMART-R C-band radar on Addu Atoll for the duration of the 6-month Extended Operations Period of DYNAMO. The radar will provide continuous measurements of reflectivity and radial velocity of precipitating convection, and serve as the "workhorse" radar of DYNAMO, allowing other radars to have more flexibility in scanning strategies. The research team will also develop baseline products to assess properties of the precipitating clouds and their organization, including: reflectivity PDFs with height, echo-top heights, convective-stratiform classification, rain maps, and rain/snow water content estimates. Divergence and latent heating profiles calculated from radial velocity and reflectivity measurements will also be developed and used to determine the balance between low-level and upper level heating in precipitating convection.The broader impacts of the work include the involvement of a large number of students in field observations and data analysis, possible outreach activities on Addu Atoll, and enhanced international collaborations. 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.