Analysis of Contrast between Two Atmospheric Circulations at Plateau Section during the Period of El-Nino

Using the NCEP/NCAR reanalysis data，this paper analyzes the characteristics of different stages of the two El-Nino events in different warmer regions，and the distribution characteristics of the wind field，temperature field and the height field of the South Asia high pressure which is above the plateau are also analyzed．Results show that the different effects of wind circulation are mainly manifested in:easterly wind enhances as a whole from the vertical profile of EP type，but to CP type，westerly wind enhances in the middle and lower classes of troposphere，and easterly wind also enhances in the upper class．On 200hPa wind field，over the plateau of EP type is abnormal wind，but CP type is an abnormal shear line; on the north side displays anomaly northeaster; on the south it shows southeast wind anomaly; On 500 hpa wind field，EP type characterizes by abnormal northeaster，but type CP shows abnormal for southeast wind．The different effects on the temperature field are mainly manifested in:EP type each has a negative anomaly center in the mid and top troposphere over Plateau，but CP type only has a negative anomaly center in the middle troposphere．The different impacts on the South Asia high is mainly manifested in:EP SAH center location tends to Southeast，but CP SAH center location tends to north．