ANALYSIS OF THE CHARACTERISTICS OF THE EAST ASIAN SUBTROPICAL WESTERLY JET UNDER DIFFERENT SCALES IN SUMMER
LONG Qingrou
JIN Ronghua
XIAO Tiangui
YANG Ning
LIU Sijia
Abstract：By using the daily reanalysis data provided by National Centers for Environmental Prediction-National Center for Atmospheric Research (NCEP-NCAR) and daily precipitation data at 20:00 BT (Beijing Time) from Chinese meteorological stations during 1960-2015,spatial distribution and activity characteristics of the East Asia subtropical westerly jet (EASWJ) in summer,which are in zonal wind wave with the ultralongwave,long wave and synoptic-scale wave,are analyzed.A preliminary study on the relationship between the EASWJ with different spatial scales and typical Meiyu precipitation is performed.Research shows that ultra long wave is the main component of the disturbance of EASWJ,highly consistent with the position evolution of the jet stream.It also has a nice indication for rain belt change in position during the period of Meiyu.In addition,long wave and synoptic scale waves are sub-low trequency and medium-scale perturbations superimposed on ultra long waves,which has a certain corresponding relationship with the change of Meiyu intensity.The position change of the EASWJ and ultra long wave has a obvious characteristics of weekly and biweekly oscillation.So,full use of ultra long wave cycle may provide valuable reference information for medium-term weather analysis and forecasting.
Keywords：East Asia subtropical westerly jetdifferent scalefeature analysismiddle-range forecasting
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：9( 1000-1008 )