中国冰川面积随高程分布规律研究

冰川面积随高程分布规律是冰川系统结构研究中的重要内容. 根据中国第一次冰川编目数据集，将全国冰川划分为27个研究区域，基于SRTM-DEM数据，分别提取了各研究区分段高程所占面积，分析了冰川面积随高程的变化. 结果表明：各研究区冰川面积都随高程呈偏态分布. 依据统计理论，建立了冰川面积随高程分布的二阶高斯分布偏态回归模型，回归模型决定系数均大于0.97，相对误差较小. 根据偏态回归模型，计算出了冰川系统高度特征值，并分析了冰川面积分布的区域性差异. 该模型一方面可以表达冰川面积在中间高程的集中程度；另一方面可以描述冰川面积在两侧分布的差异性，并可以用来分析未来冰川的变化. 偏态分布模型能很好地描述中国冰川面积随高程分布规律，为冰川系统结构的研究和冰川区域分布差异提供参考.

Study of the elevation-dependent glacierized area in China

The elevation-dependent glacierized area is an important part of the structure of glacier system. It is usually expressed by some empirical formulas which are difficult to use in hydrologic simulation. Based on SRTM-DEM, the glaciers in China were divided into 27 regions and glacierized area changing with elevation was extracted region by region according to the Glacier Inventory of China. It is found that the elevation-dependent glacierized area shows a skewed distribution in all regions. Based on statistical theory, a second-order Gaussian regression model with skewed distribution of elevation-dependent glacierized area was built, and the regression coefficients were all greater than 0.97, with smaller relative errors. A normal distribution model was also built in each region. Comparative analysis of the two methods shows that for some regions the normal distribution model is better, but for some parts it does not describe well, especially at lower elevation and higher elevation parts. The elevation structure characteristics of glacier system were computed, and the regional differences in elevation-dependent glacierized area were analyzed. On one hand, the skewed distribution model can expresses the concentration degree at the central elevation, on the other hand it can describes the differences on both sides, and can be used for the analysis of glacier variations. As a whole, skewed distribution model can well describe the elevation-dependent glacierized area, which is useful for glacier system research and for division of glaciers in China.