Abstract:

In order to scientifically determine the topographic relief characteristics of meteorological stations, based on the 30 m data of Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Model (ASTER GDEM), the optimal analysis window of relief degree of land surface (RDLS) model in Sichuan Province was determined by using the mean change point analysis method. On this basis, the relief amplitude characteristics of surface meteorological observation stations in Sichuan Province were analyzed to explore the spatial pattern of the layout of meteorological stations. The results are as follows: (1) The best window for RDLS in Sichuan Province is 39 × 39 rectangular neighborhood pixels, with a corresponding area of about 1.369 km². The established RDLS model is consistent with the trend of mountains and can capture the topographic relief of various scales, which accords with the topographic characteristics of Sichuan Province. (2) The terrain of national stations and regional stations is dominated by platforms, hills, and small undulating mountains. The proportion of national stations with small topographic undulations stations is significantly higher than that of regional stations, indicating that national stations are more representative of the region. (3) Suitable meteorological observation stations in Sichuan Province are mainly distributed the basin, in the north and west regions of the west Sichuan Plateau, as well as the eastern and southern parts of Panxi, accounting for 69.74% of the province’s total area. The analysis window area determined by the mean change point analysis method can take into consideration various geomorphic types, and the extracted RDLS can better reflect the topographic characteristics of meteorological stations, which can provide an important reference for the adaptive layout of meteorological stations and the optimization of station network.

Key words: mean change point analysis method, DEM, relief degree of land surface （RDLS）, meteorological stations, Sichuan Province

摘要：

为科学确定气象站点地形起伏特征，基于先进星载热发射和反射辐射仪全球数字高程模型（Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Model，ASTER GDEM）30 m数据，利用均值变点分析法确定四川省地形起伏度模型的最佳分析窗口。提取地面气象观测站所处的地形起伏特征，探究气象站点布设的区域代表性空间格局。结果表明：（1）四川省地形起伏度的最佳窗口为39×39个像元矩形邻域，对应面积1.369 km²。建立的地形起伏度模型与山脉走向一致，能够捕捉到地表各种尺度的地形起伏状况，符合四川省地貌特征。（2）国家站和区域站所处地势以台地、丘陵和小起伏山地为主，地形起伏较小的国家站占比明显高于区域站，即国家站更具有区域代表性。（3）四川省气象观测站点布设的适宜地区主要集中在盆地、川西高原的北部和西部及攀西地区的东部和南部，占全省面积的69.74%。均值变点分析法确定的分析窗口面积可以兼顾各种地貌类型，提取的地形起伏度能较好地反映气象站点所处地形特征，可为气象站点布局和站网优化提供重要参考依据。

关键词: 均值变点分析法, DEM, 地形起伏度, 地面气象站点, 四川省