The Investigation of Atmospheric Angular Momentum as a Contributor to Polar Wobble and Length of Day Change with AMIP II GCM Data
全球大气角动量变化的比较分析(英文)作者机构:Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 Institute of Geodesy and GeophysicsChinese Academy of Sciences Wuhan430077
出 版 物:《Advances in Atmospheric Sciences》 (大气科学进展(英文版))
年 卷 期:2002年第19卷第2期
页 面:287-296页
核心收录:
学科分类:07[理学] 070601[理学-气象学] 0706[理学-大气科学]
基 金:the National Natural Science Foundation of China under Grant Nos. 49904002 and 40074004 the National Climbing Project of China
主 题:Atmospheric Model Inter–comparison Project (AMIP) Atmospheric Angular Momentum (AAM) Earth rotation
摘 要:The atmospheric angular momentum (AAM) functions in terms of contribution to polar wobble and length of day change, are calculated from the output data of GSM9603 global circulation model (GCM) of Japan Meteorological Agency (JMA), from the reanalysis data of the National Centers for the Environmental Prediction (NCEP)/National Center for Atmospheric Research (NCAR), and from the operational objective analysis data of JMA, respectively. The comparison shows that during the period from 1985 to 1995, the values of the pressure terms in the equatorial components of AAM functions calculated from three data sets agree with each other better along 90°E longitude than along Greenwich meridian direction. The axial component of relative AAM function estimated from GSM 9603 agrees well with those from the other two data sets in terms of seasonal variations with the moderate amplitudes, but not so well with the composite axial component of relative AAM functions estimated from 23 GCM models anticipating in the first phase of AMIP. In addition, its interannual variation from 1979 to 1996 shows the main characteristics of ENSO evolution, just as does the axial component of relative AAM function estimated from NCEP reanalysis data except for the period of anomalous ENSO from 1991 to 1993.