BOREAL SUMMER CLIMATOLOGY AND STANDARD DEVIATION IN GLOBAL LOW-FREQUENCY STREAMFUNCTION FIELDS AT 200 hPa

作者：季悦,李艳杰,吴志伟

摘要：Based on NCEP/NCAR DOE daily reanalysis dataset during 1980-2015, this study investigates the boreal summer climatology and standard deviation of streamfunction in different low frequency periods(including 10-30 days,30-60 days and more than 60 days) at 200 hPa. Distinctions in the characteristics in different periods are emphasized. It is found that the distribution of streamfunction on the timescale longer than 60 days is mainly zonal symmetric,accompanied by strong variability in the Northern Hemisphere subtropical jet streams. For the 10-30-day timescale, it reflects the zonal fluctuating structure in the middle and high latitudes and large variability in the Southern Hemisphere.Tropical quadrupole structure is observed on the 30-60-day timescale in climatology. Besides, a relative weak standard deviation is also found in this period. This work provides basic knowledge on climatology and variability in low-frequency streamfunction, which has not been fully illustrated in previous studies.

发文机构：Key Laboratory of Meteorology Disaster State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Sciences

关键词：LOW-FREQUENCYstreamfunctionBOREALSUMMERCLIMATOLOGYstandarddeviation

分类号： P46[天文地球—大气科学及气象学]