Local Geoid Model Generation Using the Geometrical Approach

作     者：Mohammed Anwer Jassim Mohanad Mohsen Yousef 

作者机构：Geomatics Engineering DepartmentCollege of EngineeringSalahaddin University-ErbilErbil 44001Iraqi Kurdistan RegionIraq Duhok Polytechnical University—Zakho Technical InstituteDuhok 42001Iraqi Kurdistan RegionIraq 

出 版 物：《Journal of Civil Engineering and Architecture》 (土木工程与建筑（英文版）)

年 卷 期：2021年第15卷第8期

页      面：437-445页

学科分类：08[工学] 081601[工学-大地测量学与测量工程] 0816[工学-测绘科学与技术] 

主　　题：Geoid undulation LGM ellipsoidal height Karbala 1979 

摘      要：The global navigation satellite systems(GNSS)provide an accurate three-dimensional positioning including the geodetic(ellipsoidal)height(h),which is,in most cases,must be transformed to the local/regional orthometric height(H)to have physically the desired meaning of the elevation above the national vertical datum(e.g.,MSL(Mean Sea Level)).Usually,the local orthometric heights are determined based on the value of geoid undulation(N),which is obtained by methods of gravimetrical observations or derived by methods of interpolation utilizing the local geoid models(LGM).The current paper highlights one of the methods of generating LGM that is based on the geometrical relationship between the global datum WGS84 and the Iraqi datum Karbala *** DGPS(Differential GPS)method is used to get the geodetic coordinates of about 97 selected points to cover the experimental area,within the boundaries of Erbil municipality,which has been partitioned into four ***,four LGM were generated individually for each one of the four parts with an estimated uncertainty equal to±0.076 m.