Characterization and quantification of within-year variation of snow-cover elevation in mountainous regions, eastern Tibet

作     者：Jie Gao XuDong Fu TongLiang Gong GuangQian Wang Hao Wang 

作者机构：State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China Tibet Bureau of Water Resources Lhasa 850000 China Hydropower and Water Resources Planning ＆ Design General Institute Beijing 100120 China 

出 版 物：《Research in Cold and Arid Regions》 (寒旱区科学（英文版）)

年 卷 期：2011年第3卷第5期

页      面：400-407页

学科分类：0810[工学-信息与通信工程] 07[理学] 08[工学] 081002[工学-信号与信息处理] 0713[理学-生态学] 

基　　金：supported by the National Natural Science Foundation of China under Grant No.50221903 by the Ministry of Science and Technology of China under Grant No.2007BAC06B06 

主　　题：fluctuating snow-covered elevation (FSCE) eastem Tibet median of snow-flee period duration of snow-flee period 

摘      要：Fluctuating snow-covered elevation （FSCE） was conceptualized and proposed to characterize within-year variation of the border between snow-covered and snow-free area in mountainous regions. Two parameters, namely median of snow flee period （Tm） and snow free duration （AT）, were defined to quantify FSCE. A regression model of FSCE was developed for the Lhasa River Basin, Niyang River Basin, and Changdu region in eastern Tibet. Statistical analysis of the snow-products data with a spatial resolution of 25km×25km shows that： （1） Tm correlates weakly with geographical and topographic factors, having the yearly mean value of July 31; （2） △T correlates significantly with the average elevation of the snow-products cell, having the yearly mean value of nearly five months （i.e., 151 days）; （3） the region begins snow disappearance in late April and finishes snow coverage in mid November, being snow-free from late June to mid September and snow-covered from December to March in the next year. In addi- tion, snow-products with higher spatial resolution will be helpful to characterize FSCE in smaller spatial scales.