Studies on the Effects of the Stratosphere on Climate Change and its Dynamical Role

通过对全球观测资料的分析和数值研究，阐明了平流层变化对大气环流主要动力过程的影响及其动力作用，数值研究采用了从动力核心到日本气象厅一个月集合数值天气预报业务模式的一系列数值模式。与平流层突然增暖事件相关的一些具体发现是绕极涡边缘的大尺度锋结构和事件前后环状模态的系统可预报性变化。在上述资料和模式的基础上，还利用了一个化学气候模式，阐明了平流层冷却和太阳活动变化等外部强迫对大气季节内和年际变化的动力学影响。

Effects of the stratospheric change on the main dynamical processes of the general circulation of the atmosphere and their dynamical role were clarified with data analyses of global observations and numerical studies with a hierarchy of numerical models from a dynamical core to the JMA operational model of one-month ensemble numerical weather prediction. Some specific findings associated with a stratospheric sudden warming event are large-scale frontal structure at the edge of circumpolar vortex and systematic predictability variation of the annular mode before and after the event. A chemistry-climate model was also used in addition to the above data and models, and the dynamical influences of external forcings, such as the stratospheric cooling and variations of the solar activity, on the intra-seasonal and inter-annual variations of the atmosphere were elucidated.