Madden-Julian Oscillation (MJO) Initiation-DYNAMO (DYNAmics of the Madden-julian Oscillation) and Beyond

马登-朱利安振荡（英语：Madden-Julian Oscillation）是热带大气的一种扰动，在赤道附近的广阔区域，云和降水增加，伴随着西部或东部降水减少和云量减少的区域。 MJO事件通常开始时，对流降水爆发在印度洋的大部分地区，增强降水的区域逐渐向东传播，往往远至赤道太平洋中部才消散。 MJO事件影响了地球仪大部分地区的天气和气候，对美国产生了重大影响。2011年10月至2012年2月在印度洋进行了一项研究MJO的实地活动，名为Madden-Julian Oscillation（MJO;见AGS-1022899）。 该项目是MJO的后续项目，因为它试图将MJO运动的结果推广到比运动中观察到的区域更广泛的区域，并推广到部署期间以外发生的MJO事件。 本文提出了一种新的研究思路，即把MJO的发生看作是一个两阶段的过程，第一阶段是大范围对流降水的爆发，第二阶段是MJO向东传播的开始。 以前的工作表明存在非MJO事件，其中降水发生在热带印度洋的大部分地区，但向东传播未能发展。 该奖项下的研究试图了解为什么在某些情况下会发生向东传播，导致完全发展的MJO事件和伴随的全球影响，而不是在其他情况下。 一个假设是，该地区的降水传播是由传播的大气温度和风，这发生独立的MJO的前兆扰动，但可以与降水异常相互作用，形成一个东移MJO事件。除了其科学利益的工作具有社会意义，由于广泛的影响MJO。 例如，当MJO传播到赤道太平洋中部时，墨西哥湾和西加勒比海飓风生成的可能性更大，并且MJO还与给沿海加州带来洪水的“大气河流”事件有关。 这项工作有一个直接的联系，以改善MJO预测，通过其重点提高MJO在全球大气模型的代表性。

The Madden-Julian Oscillation (MJO) is a disturbance of the tropical atmosphere in which clouds and precipitation are enhanced over a broad region near the equator, with an accompanying region of reduced precipitation and cloudiness to the west or east. MJO events typically begin when convective precipitation breaks out over a large portion of the Indian Ocean, and the region of enhanced precipitation gradually propagates eastward, often as far as the central equatorial Pacific before dissipating. MJO events affect weather and climate over much of the globe, with substantial impacts over the US.A field campaign to study the MJO was conducted in the Indian Ocean From October 2011 to February 2012, titled Dynamics of the Madden-julian Oscillation (DYNAMO; see AGS-1022899). This project is a follow-on to DYNAMO in that it seeks to generalize the results from the DYNAMO campaign to a broader region than the area observed in the campaign, and to MJO events occurring outside the deployment period. It also seeks to use results from the campaign to understand why global weather and climate models have difficulty in simulating the initiation of the MJO.A novel approach taken in this research is to consider MJO initiation as a two stage process, in which the outbreak of widespread convective precipitation is the first stage and the onset of eastward propagation is the second. Previous work shows the existence of non-MJO events, in which precipitation occurs over much of the tropical Indian Ocean but eastward propagation fails to develop. Research under this award attempts to understand why eastward propagation occurs in some cases, resulting in a fully developed MJO event and accompanying global impacts, but not in others. One hypothesis is that propagation of the region of precipitation is initiated by propagating precursor disturbances in atmospheric temperature and winds, which occur independently of the MJO but can interact with the precipitation anomalies to form an eastward moving MJO event.Beyond its scientific interest the work has societal relevance due to the widespread impacts of the MJO. For example, the likelihood of hurricane genesis in the Gulf of Mexico and western Caribbean hurricane genesis is much more likely when the MJO propagates into the central equatorial Pacific, and the MJO is also linked to "atmospheric river" events that bring flooding to coastal California. This work has a direct connection to improving MJO predictions through its emphasis on improving the representation of the MJO in global atmospheric models.