利用GRACE数据反演东海沉积物变化  

Inversion for sediment variation in the East China Sea using GRACE data

作　　者：李圳[1,2] 章传银 柯宝贵[1] 乔灵娜[1,3] 李婉秋 刘阳 LI Zhen;ZHANG ChuanYin;KE BaoGui;QIAO LingNa;LI WanQiu;LIU Yang(Chinese Academy of Surveying and Mapping,Beijing 100830,China;GNSS Research Center,Wuhan University,Wuhan 430079,China;College of Geomatics,Shandong University of Science and Technology,Qingdao 266510,China)

机构地区：[1]中国测绘科学研究院,北京100830 [2]武汉大学卫星导航定位技术研究中心,武汉430079 [3]山东科技大学测绘科学与工程学院,青岛266510

出　　处：《地球物理学报》2019年第7期2429-2440,共12页Chinese Journal of Geophysics

基　　金：国家重点研发计划(2016YFB0501702);国家自然科学基金项目(41374081,41574004);山东科技大学研究生创新项目(SDKDYC180312);地理国情专题监测项目(WHJT-CZH-2017-1C104)资助

摘　　要：GRACE卫星的成功发射为海底沉积物的监测提供了新的方法.利用2003-2014年间的GRACERL05数据,采用同期的测高数据对海面高变化进行改正,使用水文模式数据和基于均一假设的尺度因子估计方法处理泄漏误差,反演了东海地区的沉积物变化情况,并对GIA效应进行了改正.结果表明:东海入海口处沉积物的平均变化速率为5.44±0.88mm·a^-1,最大值出现在浙江沿海地区,变化速率为6~7mm·a^-1;在空间分布上,呈现河口处沉积速率大,远离河口的大洋地区沉积速率小的特征.在时空分布上均与实测数据很好的吻合.沉积物变化时间序列的周年项振为6.8cm,周年变化主要与东海泥沙扩散路径相关的海洋环流模式有关;半周年项和两周年项振幅分别为0.6cm和0.7cm,这两项变化主要与长江流域降水引起的土壤侵蚀变化有关.最后,分析讨论了本文沉积物监测方法推广到其他地区的适用性和局限性.The Gravity Recovery and Climate Experiment (GRACE) mission provides a new tool to detect the variation of seabed sediment. We used GRACE GSM products from three data centers to determine sediment mass accumulation rates and variability in the East China Sea. Furthermore,GRACE GAD data was used to restore the atmospheric and oceanic effects in order to avoid model contaminations on gravity signals associated with sediment mass. The improved P3M9 de-correlated filter and fan filter were used to improve the quality of gravity signals from GRACE. What's more,the monthly mean maps of sea level anomaly (MSLA) products from altimeter data were also used to correct the variation of sea level. For the leakage error,we used a hydrological model and estimate scale factor based on uniform assumption to deal with the leakage-in and leakage-out errors,respectively. Finally,we also corrected the GIA (Glacial Isostatic Adjustment) effect. Results indicate that sediment mass accumulation rate at the estuary of the East China Sea was 5.44±0.88 mm·a^-1 ,with maximum about 6~7 mm·a^-1 in the coastal area of Zhejiang Province. And in terms of its spatial distribution,the rate at the estuary is larger compared to the smaller rate in the ocean areas far away from coast. Moreover,the temporal-spatial distribution between calculated results and measured data are in good agreement. As far as is concerned to the time series,the amplitude of semi-annual oscillation is 0.6cm,which is related to the seasonal reversals of East Asian monsoon winds. The annual oscillation can be qualitatively explained by the ocean circulation pattern associated with the sediment dispersal path in the East China Sea,and sediment variation is highly influenced by the ocean circulation pattern,so the amplitude of annual oscillation is 6.8 cm,obviously higher than the semi-annual and quasi-biennial oscillation. And the amplitude of quasi-biennial oscillation is 0.7 cm, such an oscillation may be related to the atmospheric circulation that causes a precipitation

关 键 词：GRACE 卫星测高 东海 沉积物 泄漏误差 

分 类 号：P229[天文地球—大地测量学与测量工程]