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

马登-朱利安涛动（DYNAMO）场运动的动力学是2011年底/ 2012年初在印度洋进行的一项国际实验——印度洋季节内变率合作实验（CINDY2011）的美国组成部分。DYNAMO的总体目标是加快对印度洋MJO形成的关键过程的理解，并改进对MJO的模拟和预测。实地考察活动将包括多部雷达、大气探测站点、一架研究飞机、多艘研究船和海洋测量。DYNAMO的三个主要假设是：1)只有当湿层在MJO尺度上足够深时，深层对流才能组织成MJO对流包络；2)不同阶段的特定对流种群对MJO的形成至关重要；3)屏障层、风和剪切驱动的混合、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表温度，从而控制表面通量反馈，对印度洋MJO的形成起着重要作用。在为期6个月的DYNAMO扩展操作期间，调查人员将在Addu Atoll部署SMART-R c波段雷达。该雷达将提供降水对流反射率和径向速度的连续测量，并作为DYNAMO的“主力”雷达，使其他雷达在扫描策略上具有更大的灵活性。研究小组还将开发基线产品，以评估降水云及其组织的特性，包括：带高度的反射率pdf文件、回波顶高度、对流层状分类、雨量图和雨/雪水含量估算。根据径向速度和反射率测量计算的散度和潜热剖面也将得到发展，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批学生参与实地观察和数据分析，可能在阿杜环礁开展外联活动，以及加强国际合作。一个成功的DYNAMO活动将提高对热带对流、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认识。

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.