夏季准定常环流系统及其月内演变特征的数值模拟

NUMERICAL SIMULATION OF RPOPERTIES OF SUMMER QUASI STATIONRY CIRCULATION SYSTEMS WITH THEIR INTRAMONTHLY EVOLUTIONS

用球带范围的耦合模式，研究了夏季准定常环流系统的基本特征及其月内时间演变过程，发现在北半球中高纬，无论在大气高层还是低层，环流形势均具有纬向两波结构，与纬向海陆分布的两波结构完全吻合，从而证明了海陆分布是造成准定常环流系统的根本原因。准定常环流系统的时间变化主要发生在前２０个模式日中，变化最明显的地区通常也是准定常环流系统的中心。

Study is undertaken of basic characteristics of summer quasi-stationary circulationsystems(QSCS)and their intramonthly evolutions by use of a zonal coupled(sea- air and land-air)model.Results show that at Northern Hemisphere extratropics,the high-and low-levelQSCS's are all featured by a zonal bi-wave structure,in complete agreement with the land- seadistribution over the belt,thereby confirming that the geographic pattern is the underlying causeof the QSCS's which show temporal variation largely in the first 20 model days,with the area ofstrongest change generrally being the core of the system.