A Novel Model for Terrain Slope Estimation Using ICESat/GLAS Waveform Data
A Novel Model for Terrain Slope Estimation Using ICESat/GLAS Waveform Data
复制标题
利用ICESat/GLAS波形数据估计地形坡度的新模型
DOI：
10.1109/tgrs.2017.2745107
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发表时间：
2018-01-01
影响因子：
8.2
通讯作者：
Yang, Xuebo
中科院分区：
文献类型：
--
作者：
Nie, Sheng;Wang, Cheng;Yang, Xuebo
地形坡度的准确估计对于利用激光高度计准确监测冰川高程和质量变化至关重要。本文提出了一种新的物理模型，用于精确估计足迹内地形坡度。新提出的模型是建立在重叠的足迹的地球科学激光高度计系统（GLAS）的数据，即，使用高度角，足迹大小，形状，方向，地形方面，和地面范围。分别建立了基于GLAS波形宽度与机载地形测绘仪（ATM）波形宽度和ATM波形宽度之间的线性回归模型。此外，根据重叠足迹估计的地形坡度通过ATM数据进行了验证，并与根据地表高程计算的坡度进行了比较，即，从ASTER全球数字高程模型（DEM）（GDEM）和GLAS高程。结果表明，波形宽度预测地表范围的精度（R ^{2}= 0.868 $，RMSE = 0.686 m，$n = 20 $，$p $-value <0.0001）高于波形范围预测地表范围的精度（R ^{\mathbf {2}}}= 0.776 $，RMSE = 0.824 m，$n = 20 $，$p $-value <0.0001），表明波形宽度更适合于地表范围的估计。<inline-formula><tex-math notation="LaTeX"></tex-math></inline-formula><inline-formula><tex-math notation="LaTeX"></tex-math></inline-formula><inline-formula><tex-math notation="LaTeX"></tex-math></inline-formula><inline-formula><tex-math notation="LaTeX"></tex-math></inline-formula><inline-formula><tex-math notation="LaTeX"></tex-math></inline-formula><inline-formula><tex-math notation="LaTeX"></tex-math></inline-formula>新模型估计的斜率与ATM数据计算的斜率具有很强的一致性（Corrcoef = 0.786，bias = 0.654 °，SD = 1.368 °，RMSE = 1.452 °）。此外，研究结果还表明，新提出的模型表现得更好的方法比基于ASTER GDEM和GLAS表面高程在估计足迹内的地形坡度，由于更高的相关性，更低的偏差，标准差，和RMSE。
The accurate estimation of terrain slope is very important for accurately monitoring the elevation and mass changes of glacier using laser altimeter. In this paper, a novel physical model was proposed for accurately estimating within-footprint terrain slope. The new proposed model was built based on overlapping footprints of the geoscience laser altimeter system (GLAS) data, namely, using altitude angle, footprint size, shape, orientation, terrain aspect, and ground extent. Ground extent estimation models were established on the basis of linear regression analyses between: 1) GLAS-derived waveform extent and airborne topographic mapper (ATM)-derived ground extent and 2) GLAS-derived waveform width and ATM-derived ground extent, respectively. In addition, the terrain slopes estimated from the overlapping footprints were validated by ATM data and compared with the slopes calculated from surface elevations, i.e., from ASTER global digital elevation model (DEM) (GDEM) and GLAS elevation. Results showed that the accuracy of waveform width-predicted ground extents (<inline-formula> <tex-math notation="LaTeX">$R^{2} = 0.868$ </tex-math></inline-formula>, RMSE = 0.686 m, <inline-formula> <tex-math notation="LaTeX">$n = 20$ </tex-math></inline-formula>, and <inline-formula> <tex-math notation="LaTeX">$p$ </tex-math></inline-formula>-value < 0.0001) is higher than that of waveform extent-predicted ground extents (<inline-formula> <tex-math notation="LaTeX">$R^{{\mathbf {2}}} = 0.776$ </tex-math></inline-formula>, RMSE = 0.824 m, <inline-formula> <tex-math notation="LaTeX">$n = 20$ </tex-math></inline-formula>, and <inline-formula> <tex-math notation="LaTeX">$p$ </tex-math></inline-formula>-value < 0.0001), which indicated that waveform width is more suitable for estimating ground extent. Slopes estimated from the new proposed model have a strong consistency with those calculated from ATM data (Corrcoef = 0.786, bias = 0.654°, SD = 1.368°, and RMSE = 1.452°). Additionally, results also indicated that the new proposed model performs much better than the methods based on ASTER GDEM and the GLAS surface elevation in estimating within-footprint terrain slope due to higher correlation, lower bias, standard deviation, and RMSE.