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，并对从动力核心到JMA一个月综合数值天气预报业务模式的数值模式进行了分级研究。与平流层突然变暖事件相关的一些具体发现是：环极涡边缘的大尺度锋面结构和事件前后环模的系统可预测性变化。在上述数据和模式的基础上，利用化学-气候模式分析了平流层降温和太阳活动变化等外部强迫对大气季节和年际变化的动力影响。

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.