基于地表负载一阶变化反演季节性地球形变

Seasonal Earth Deformation from the Change of the Degree-1 Surface Mass Load

基于SNREI地球模型,利用IGS数据反演得到近10a的地表负载力矩变化,探索了季节性地球形变机制,发现地表负载力矩在mx、my、mz三个方向均有明显的周年项变化,进而指明固体地球也存在明显的季节性形变。mz方向的相位表明,每年的2、3月份北半球地表负载最大,而8、9月份南半球地表负载最大;每年的12月份地表负载力矩出现在中国境内,将会导致中国范围的测站在水平和垂直方向分别产生1mm和2mm左右的位移,这个位移量级对我国mm级CGCS2000框架所造成的影响是不容忽视的。

This article is based on SNREI earth model,inverting earth＇s surface load moment of recent10 years by IGS data,explored the mechanism of seasonal earth deformation,and the results indicate that surface load moment has significant annual changes in mx,myand mzdirections,and then there exists obvious seasonal deformation of the solid earth.The phase in mz direction shows that,the maximum surface mass load within northern hemisphere is between February and March of each year,and that of southern hemisphere is between August and September,the load moment occurs within China during every December,which will cause the stations within China have a downward deformation of 2mm and a lateral deformation of 1mm,and this influence for maintaining the stability of our millimeter level CGCS2000 reference frame cannot be ignored.