湖南地区似大地水准面模型再精化研究

湖南地区2007版似大地水准面模型存在数据源质量相对不高、局部区域存在粗差等问题。通过引入EGM2008地球重力场模型、高分辨率DEM数据、高精度GPS/水准数据等新数据源,采用最小二乘配置法与格林基函数样条插值算法,在原有模型的基础上得到1′×1′分辨率的再精化新模型。精度检测结果表明,新模型的内、外符合精度相较2007模型提升80.7%和22.9%,有效降低汉寿等地区的残差,对湖南省地区的复杂地形具有更好的适用性。

Research of Hunan quasi-geoid model refining

There are several problems in the current quasi‐geoid model established in Hunan area in 2007 , such as the low quality of data source ,and the gross error in some local areas .In this paper ,a new quasi‐geoid model with 1′× 1′ high resolution based on the existing one is established by using the new data source .Meanwhile ,the EGM2008 earth gravity model ,DEM with high resolution ,and precise GPS/leveling data are introduced to improve the accuracy and reliability .Both the least‐squares approach and Green function‐based spline interpolation algorithm are also used for the refinement of the new quasi -geoid model .The results of accuracy tests show that the inner and external coincidence precision of the new model is significantly superior compared to the existing one by increasing 80 .7% and 18 .8% , respectively .It also can be seen that the residual error of the new model decreases effectively in some local areas ,for example ,Hanshou Region in Changde City ,w hich indicates the better performance of the new model for the complex topographic feature in Hunan area .