The monthly wind field of NCEP/NCAR reanalysis data is used to define an intensity index of the East Asia subtropical westerly jet, which can reasonably reflect the impact of the East Asia subtropical westerly jet on summer precipitation in North China.

Sensitive experiments were performed by using a regional climate model with p-σ incorporated coordinate to investigate the impacts of the uplift of the Tibetan Plateau on the East Asian subtropical westerly jet(EAWJ).

They are (1) preparation stage of Subtropical westerly jet (from May to September); (2) Development stage of jet from October to March; (3) the jet disappearing and replacing by west pacific subtropical high from May to September.

Utilizing the radiosonde observation data during the 30 years(1961-1991),we calculate the vertical 16 layers distribution of subtropical westerlies jet in winter,and on the basis of the distribution model to regress the main pluvial regions year by year(according to two standards,i.

Using the monthly mean reanalysis datasets from the NCAR/NCEP,relationships of the interannual variation between an eastern Asia[CD*2]Pacific dipole(APD) mode and the East Asian subtropical monsoon are studied.

The European Center for Medium-Range Weather Forecasts reanalysis data sets and the observed data for precipitations and temperatures in China are used to depict the relationships between the eastern China climate and the East Asian jet stream(EAJS).

The background large-scale circulation changes include the intensification of the western Pacific subtropical high(WPSH) and the southwest shift of the East Asian jet stream(EAJS).