Using the equatorial balanced model and the low-corder spectral method to consider the effect of the basic flow, the primary and secondary shear flows, the nonlinear equation describing the winter and summer monsoon i...Using the equatorial balanced model and the low-corder spectral method to consider the effect of the basic flow, the primary and secondary shear flows, the nonlinear equation describing the winter and summer monsoon in south Asia is derived. The stress is on the influence of the flows on the formation,transformation and intensity of the monsoon in south Asia. The results show that the influence on the monsoon in south Asia is significantly different among the primary shear flow, the basic flow and the secondary shear flow.展开更多
A case is reported, during which the Subtropical High over the Western Pacific (hereafter, SHWP in abbreviation) shifted northwestward and met-yu at Chaniiang River valley ended. Several numerical experiments onSHWP a...A case is reported, during which the Subtropical High over the Western Pacific (hereafter, SHWP in abbreviation) shifted northwestward and met-yu at Chaniiang River valley ended. Several numerical experiments onSHWP activity influenced by the heating over south Asia monsoon area are carried out, and the statistic significance of the results is checked. The results indicate that the enhancement of positive heating over South Asia willmotivate a wave-like series of anomaly centers, which propagate northeastward from the maximum heating center.so that a strong positive potential height anomaly center will set up from North China to Japan at Day X resultingin the enhancement of SHWP. Comparison of the influence upon SHWP by the heating over south Asia monsoonarea with that over ITCZ area south to SHWP is also carried out. It is pointed out that the heating over South Asiamonsoon area tends to favor SHWP north\vard movement while the heating over ITCZ area tends to thvor SHWPwestward stretching. As for the time to begin to influence on SHWP, the heating over south Asia monsoon areafavors the enhancement of SHWP atter Day 3 while that over ITCZ south to SHWP effects atter Day 5.展开更多
基于1968—1997年美国国家大气研究中心/美国国家环境预报中心(National Center for Atmospheric Research/National Centers for Environmental Prediction,NCAR/NCEP)共30 a平均的全球各标准等压面上经纬网格距为2.5°×2.5&#...基于1968—1997年美国国家大气研究中心/美国国家环境预报中心(National Center for Atmospheric Research/National Centers for Environmental Prediction,NCAR/NCEP)共30 a平均的全球各标准等压面上经纬网格距为2.5°×2.5°的逐日气候风场资料,对南海夏季风和南亚夏季风建立期间气候逐日风场的相似度进行了分析。结果表明:风场相似度能较好地反映亚洲热带夏季风的建立,在南海夏季风和南亚夏季风建立期间的季风区,对流层低层风场相似度等值线的水平梯度较大,可视为"相似度锋区",季风沿其法线方向推进。在南海夏季风和南亚夏季风建立过程中,对流层低层大气环流的变化较中层剧烈。在对流层低层,气候状态的南海夏季风最早在西太平洋暖池洋面建立,数日后则已覆盖整个南海,南海和南亚夏季风建立是低层大气环流的突变过程;相应南亚夏季风则最早在赤道东印度洋和赤道西印度洋建立,进而覆盖整个南亚次大陆,其突变性不及南海夏季风。亚洲热带夏季风建立时除季风区及附近外,在全球个别地区大气环流的调整也相当剧烈,甚至发生突变。展开更多
文摘Using the equatorial balanced model and the low-corder spectral method to consider the effect of the basic flow, the primary and secondary shear flows, the nonlinear equation describing the winter and summer monsoon in south Asia is derived. The stress is on the influence of the flows on the formation,transformation and intensity of the monsoon in south Asia. The results show that the influence on the monsoon in south Asia is significantly different among the primary shear flow, the basic flow and the secondary shear flow.
文摘A case is reported, during which the Subtropical High over the Western Pacific (hereafter, SHWP in abbreviation) shifted northwestward and met-yu at Chaniiang River valley ended. Several numerical experiments onSHWP activity influenced by the heating over south Asia monsoon area are carried out, and the statistic significance of the results is checked. The results indicate that the enhancement of positive heating over South Asia willmotivate a wave-like series of anomaly centers, which propagate northeastward from the maximum heating center.so that a strong positive potential height anomaly center will set up from North China to Japan at Day X resultingin the enhancement of SHWP. Comparison of the influence upon SHWP by the heating over south Asia monsoonarea with that over ITCZ area south to SHWP is also carried out. It is pointed out that the heating over South Asiamonsoon area tends to favor SHWP north\vard movement while the heating over ITCZ area tends to thvor SHWPwestward stretching. As for the time to begin to influence on SHWP, the heating over south Asia monsoon areafavors the enhancement of SHWP atter Day 3 while that over ITCZ south to SHWP effects atter Day 5.
文摘基于1968—1997年美国国家大气研究中心/美国国家环境预报中心(National Center for Atmospheric Research/National Centers for Environmental Prediction,NCAR/NCEP)共30 a平均的全球各标准等压面上经纬网格距为2.5°×2.5°的逐日气候风场资料,对南海夏季风和南亚夏季风建立期间气候逐日风场的相似度进行了分析。结果表明:风场相似度能较好地反映亚洲热带夏季风的建立,在南海夏季风和南亚夏季风建立期间的季风区,对流层低层风场相似度等值线的水平梯度较大,可视为"相似度锋区",季风沿其法线方向推进。在南海夏季风和南亚夏季风建立过程中,对流层低层大气环流的变化较中层剧烈。在对流层低层,气候状态的南海夏季风最早在西太平洋暖池洋面建立,数日后则已覆盖整个南海,南海和南亚夏季风建立是低层大气环流的突变过程;相应南亚夏季风则最早在赤道东印度洋和赤道西印度洋建立,进而覆盖整个南亚次大陆,其突变性不及南海夏季风。亚洲热带夏季风建立时除季风区及附近外,在全球个别地区大气环流的调整也相当剧烈,甚至发生突变。
