Collaborative Research: DYNAmics of the Madden Julian Oscillation/DYNAMO Mooring

目前对Madden-Julian振荡(MJO)的预测能力有限，尤其是对于印度洋上空的初始阶段。最先进的全球模式无法再现MJO，这降低了它们的季节性到年际预测，并降低了人们对它们预测未来气候的能力的信心。迪纳摩的总体目标是加速我们对印度洋上启动MJO的关键过程的理解，并帮助改进对MJO的模拟和预测。迪纳摩实地行动被提议作为CINDY2011(2011年印度洋内部季节内变化合作试验)的美国组成部分，CINDY2011是计划于2011年10月至2012年3月在赤道中印度洋地区开展的国际实地考察计划。四个国家(澳大利亚、印度、日本和美国)将参加。该野外计划旨在观察MJO启动期间云团的结构和演变、它们与大尺度环境的相互作用以及海-气相互作用过程。三个上层海洋/表面通量系泊装置(迪纳摩系泊装置)将用于研究赤道印度洋表层混合层和层化温跃层中的海洋过程及其对MJO发生和演变的影响。科学目标是量化和了解上层海洋与MJO事件相互作用时的预适应、演化和恢复的动力学，从而为MJO数值模式的参数化方案提供准确的物理依据。与MJO耦合的关键高空过程包括：(1)地面混合层底部的湍流热通量，(2)障碍层，(3)Wyrtki急流，(4)浅层塞舌尔-查戈斯温跃层脊，(5)地面强迫、混合层过程和湍流通量的日变化。确定了这些海洋过程影响的可检验假设，并将利用3.5个月的上层海洋过程和赤道印度洋上的湍流通量的连续观测来处理这些假设。系泊阵列将部署在雷达探测阵列的中心，该阵列由两艘船和两个岛屿站组成，代表着迪纳摩/CINDY2011计划的核心观测组件。每个系泊设备将配备气象传感器、CTD传感器阵列、系泊微结构传感器(Pod)和ADCP。更多的吊舱阵列将部署在附近的三个拉玛系泊平台上。结合迪纳摩其他大气和海洋成分的测量，我们将详细重建表层混合层、障碍层、浅层塞舌尔-查戈斯温跃层脊线、Wyrtki急流和赤道湍流通量对MJO的响应(恢复)。智慧价值：迪纳摩系泊设备将提供对印度洋海洋障碍层、上层海洋混合和夹带、海-气相互作用以及整个表层混合层过程的观测，这些都是MJO启动的关键。这些观测将为模型师、理论家和其他观察组提供，以更好地了解和预测热带气候系统。这些观测将提供对海洋过程与MJO相互作用的物理洞察，并导致基于物理的参数化，这将提高MJO预测技能。更广泛的影响：该项目将向年轻科学家介绍热带气候系统中复杂的多尺度和海-气相互作用问题。发电机观测将被用于校准和验证卫星反演，使其在与MJO有关的问题之外的更广泛的领域得到应用。来自迪纳摩活动的改进的MJO模拟和预测将增强在季节内时间尺度上为社会风险管理和决策提供预测和评估产品的能力，并增强对气候模拟和预测的信心。

Current prediction skill for the Madden-Julian Oscillation (MJO) is limited, and particularly poor for the initiation phase over the Indian Ocean. The inability of state-of-the-art global models to reproduce the MJO degrades their seasonal to inter-annual prediction and lessens confidence in their ability to project future climate. The overarching goal of DYNAMO is to expedite our understanding of processes key to MJO initiation over the Indian Ocean and to help improve simulation and prediction of the MJO.The DYNAMO field campaign is proposed as the US component of CINDY2011 (Cooperative Indian Ocean Experiment on Intraseasonal Variability in 2011), an international field program planned for October 2011 - March 2012 in the equatorial central Indian Ocean region. Four countries (Australia, India, Japan, and the US) will participate. This field program is designed to observe the structure and evolution of cloud populations, their interaction with the large-scale environment, and air-sea interaction processes during MJO initiation. An array of three upper-ocean / surface-flux moorings (DYNAMO moorings) will be used to study oceanic processes in the surface mixed layer and the stratified thermocline in the equatorial Indian Ocean and their effects on the initiation and evolution of MJO. The scientific goals are to quantify and understand the dynamics of the preconditioning, evolution, and recovery of the upper ocean as it interacts with MJO events and, thereby, to provide accurate physics to parameterization schemes in numerical models of the MJO. Key upper oceanic processes crucial to the coupling with the MJO include: (1) turbulence heat flux at the base of the surface mixed layer, (2) barrier layer, (3) Wyrtki jet, (4) shallow Seychelles-Chagos Thermocline Ridge, and (5) diurnal variation of surface forcing, mixed layer processes, and turbulence flux. Testable hypotheses for effects of these oceanic processes are identified and will be tackled using 3.5-month continuous observations of the upper ocean processes and turbulence flux across the equatorial Indian Ocean. The mooring array will be deployed in the center of a radar sounding array consisting of two ships and two island stations, representing the core observational components of the DYNAMO/CINDY2011 program. Each mooring will be equipped with meteorological sensors, arrays of CTD sensors, moored microstructure sensors (pods), and ADCPs. Additional arrays of pods will be deployed on three nearby RAMA moorings. Combined with measurements from other atmospheric and oceanic components of DYNAMO, we will develop a detailed reconstruction of the response (recovery) of the surface mixed layer, barrier layer, shallow Seychelles-Chagos thermocline ridge, Wyrtki jet, and equatorial turbulent flux to (from) the MJO. Intellectual Merit: DYNAMO moorings will provide observations of the ocean barrier layer, upper-ocean mixing and entrainment, air-sea interaction, and overall surface mixed layer processes in the Indian Ocean which are key to the MJO initiation. These observations will be available to modelers, theoreticians, and other observational groups to better understand and predict the tropical climate system. The observations will provide physical insight into the interaction of oceanic processes with the MJO and lead to physics-based parameterizations that will improve MJO prediction skill.Broader impact: The project will introduce young scientists to complex multi-scale and air-sea interaction problems in the tropical climate system. DYNAMO observations will be used to calibrate and validate satellite retrievals, benefiting their application to much broader areas beyond MJO-related problems. Improved MJO simulation and prediction born from DYNAMO activities will enhance the capacity to deliver prediction and assessment products on intra-seasonal timescales for societal risk management and decision making, and to strengthen confidence in climate simulation and projection.