Abstract: ICESat/GLA14 is a series of high accuracy altitude point. Taking Lvliang Mountain,Shanxi Province, China as the study area,the vertical error of ICESat/GLA14 v33 and ICESat/GLA14 v34 data were analyzed firstly, both the mean value and standard deviation were less than 0.01 m. Then the paper analyzed the vertical error distribution changes with different topographical factors(elevation,slope and aspect),different NDVI and landuse classes. The results show when the elevation is lower than 2 000 m,the mean absolute error of vertical error is stable,but increasing when the elevation is between 2 000 m to 3 500 m. With the increasing of slope,the mean value of vertical error rises from 0.004 m to 0.009 m. The mean value of vertical error in flat area is 0.002 m,but 0.007 m in other areas. Both the mean value and the standard deviation of vertical error are high when the land is covered with vegetation. In other words,with the increasing of elevation and slope,the vertical error increases; the accuracy of the data is high in flat area;at the same time,it is greatly influenced by vegetation. According to the results,we proposed three possible reasons:(1) the new variable,GmC(Gaussian vertical control point), which is the value applied to correct the G-C elevation problem discovered in releasing v33 and is defined as the difference in the transmit pulse Gaussian fit and the centroid of the transmit pulse;(2) atmospheric delay,that is, many other substances contained in the atmosphere will result in uneven refractive index,which further leads to refraction,scattering and delay in the process of laser pulse propagation;(3) ICESat laser footprint contains the information of vegetation,surface and many other features which may easily result in the distortion of a single element study. The aim of the study is to make a deep understanding about the quality of ICESat/GLA14 in Lvliang Mountain.

Key words: ICESat/GLA14, Lvliang Mountain, topographic, NDVI, landuse