The Madden-Julian Oscillation in General Circulation Models: An Analysis of Factors Relevant to Its Initiation, Maintenance, and Suppression

该项目将改进气候模型中季节内变化的建模。马登-朱利安涛动(MJO)是季节内变率的重要组成部分，对全球热带和亚热带地区的环流和降水变率起着重要的调节作用。MJO还影响亚澳夏季风，甚至可能影响ENSO的变异性。目前的气候模型在模拟MJO变化方面明显不足。由于被夹在两个显著的波动时间尺度之间--较短的时间尺度天气和较长时间尺度的季节至年际变化--MJO直到最近才受到重大研究关注。Randall、Demott和Khairoutdinov博士(都来自科罗拉多州立大学)将在一个云被分解(而不是参数化)的气候模型中研究MJO可变性的启动和演变。将在NCAR社区气候系统模式(CCSM)中实施云解析方案。项目任务将包括改进这一方案，并确定MJO模拟对实施的各个方面的敏感性。PIS将开发一个针对MJO变异性的诊断分析包，并通过CCSM网站提供给社区使用。

The project will improve the modeling of intra-seasonal variability in climate models. The Madden-Julian Oscillation (MJO) is a key component of intra-seasonal variability, and plays a significant role in modulating circulation and precipitation variability in the global Tropics and subtropical regions. MJO also influences the Asian-Australian summer monsoons and possibly even ENSO variability. Current climate models are notably deficient in simulating MJO variability. Because of being sandwiched between two notable fluctuation time-scales-the shorter time-scale weather and the longer time-scale seasonal-to-interannual variability-MJO has not received significant research attention until recently. Drs. Randall, Demott and Khairoutdinov (all from Colorado State University) will investigate the initiation and evolution of MJO variability in a climate model in which clouds are resolved (and not parameterized). A cloud-resolving scheme will be implemented in the NCAR Community Climate System Model (CCSM). Project tasks will include refining this scheme, and ascertaining the sensitivity of MJO simulation to various aspects of the implementation. The PIs will develop a diagnostic analysis package targeting MJO variability, and make it available for community use through the CCSM web site.