全球地表水储量再分布对周年极移的激发  

Excitation of Hydrologic Contributions on Annual Wobble

作　　者：钟敏[1,2] 闫昊明[1] 朱耀仲[1] 高布锡[1] 

机构地区：[1]中国科学院测量与地球物理研究所动力大地测量学重点试验室 [2]中国科学院大气科学和地球流体力学数值模拟国家重点实验室 北京 100029

出　　处：《天文学报》2002年第2期212-220,共9页Acta Astronomica Sinica

基　　金：国家自然科学基金(批准号:49904002;40074004);中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室开放基金共同资助

摘　　要：利用全球降水和蒸发观测同化资料以及国际大气模式比较计划和国际大气海洋耦合模式比较计划中的陆面过程数值模式,计算比较了地表水储量角动量变化对周年极移的激发.分析结果表明基于3种资料的地表水储量角动量变化对极移周年正向频率的激发约占大气周年正向激发的10%至25%.研究结果尽管显示大气、海洋和地表水的综合周年正向激发与极移测地周年正向激发十分相近,鉴于海洋角动量数值分析的差异和目前对全球水循环观测的水准以及对水循环平衡问题有限的理解,仍然期待更为客观的全球海洋、陆面动力过程和数值分析方法用于完善全球地表水储量变化对周年极移激发的研究.The excitation of hydrologic contributions to the annual wobble is investigated, based upon monthly reanalysis data of global land process taken from the Comprehensive Ocean-Atmosphere Data Set(COADS), and monthly data simulated by an atmospheric general circulation model (GSM9603) and a coupled ocean-atmospheric general circulation model (GCM-II), respectively. The geodetic excitation functions are inferred from the observed wobble in SPACE97 for the period 1985-1995. These three hydrologic contributions present some difference, but their prograde contributions cover 10% to 25% of the atmospheric prograde contribution calculated from the operational objective analysis data of Japan Meteorological Agency (JMA), which reconfirms the hydrologic contribution as an important source for the annual wobble. The F1and F2 components of hydrologic prograde contributions deduced from GOADS, GCM-II and GSM9603 are (0.30×10-8, -0.84×10-8), (0.74×10-8, 1.68×10-8 ) and ( -0.14×10-8, 1.31×10-8 ), respectively. Despite two prograde combinations of atmospheric, oceanic and hydrologic contributions tend to be much similar to the geodetic excitation function at the same period from 1985 to 1995, it is not confidently concluded which hydrologic contribution represents the relative objective one due to the obvious difference of oceanic contributions calculated from different oceanic general circulation models.

关 键 词：天体测量学 地表水储量 周年极移 降水观测 大气 陆面过程数值模拟 

分 类 号：P127.4[天文地球—天体测量]