Resources Science ›› 2020, Vol. 42 ›› Issue (12): 2434-2450.

### Spatiotemporal variations of snow cover in the Qinghai-Tibetan Plateau from 2000 to 2019

YE Hong1(), YI Guihua2(), ZHANG Tingbin1,3, ZHOU Xiaobing4, LI Jingji3,5, BIE Xiaojuan2, SHEN Yilin1, YANG Zhenglan1

1. 1. College of Earth Science, Chengdu University of Technology, Chengdu 610059, China
2. College of Tourism and Urban and Rural Planning, Chengdu University of Technology, Chengdu 610059, China
3. State Environmental Protection Key Laboratory of Synergetic Control and Joint Remediation for Soil & Water Pollution, Chengdu 610059, China
4. Geophysical Engineering Department, Montana Tech of the University of Montana, Butter 59701, USA
5. College of Ecological Environment, Chengdu University of Technology, Chengdu 610059, China
• Received:2019-12-13 Revised:2020-08-08 Online:2020-12-25 Published:2021-02-25
• Contact: YI Guihua E-mail:18883344821@163.com;yigh@cdut.edu.cn

Abstract:

Snow cover, as the most important component of the cryosphere, affects the atmospheric circulation and regional water balance, and is very sensitive to climate change. Using 8-day snow cover data of the Moderate Resolution Imaging Spectro-radiometer/Terra (MODIS/Terra) from 2000 to 2019, the interannual, annual, and seasonal spatiotemporal characteristics of snow cover in the Qinghai-Tibetan Plateau (QTP) and its variation trends were discussed. The results show that: (1) In recent 20 years, the snow cover in the QTP consisted largely of short-term snow. The spatial distribution of snow cover with one month or shorter duration was the widest, accounting for 72.91% of the total snow-covered area. The longer the snow duration, the higher the snow cover ratio (SCR). The multi-year mean SCR in the mountains surrounding the QTP was high, while the SCR was low in the Qiangtang Plateau, the source region of the rivers, and the Qaidam-Huanghuang high-medium basin, among others. (2) Snow cover area showed repeated fluctuating increase and then decrease with a relative change rate of -15.97%~11.52% during 2000-2019 in the QTP. Snow cover ratio in most areas of the Hengduan Mountains, the Pamirs Plateau, and the Qiangtang Plateau showed an obvious decreasing trend. In the areas surrounding the QTP with high mountains and extremely high mountains of huge difference in relief, hilly mountain plain in the source area of the Yangtze River and the Yellow River, and high mountain areas of medium or great difference in relief of the upper reaches of the Yangtze River and the Yellow River, a significant increasing trend of SCR in recent 20 years was observed. (3) The snow-covered area showed a bimodal cyclical trend annually, reaching the peak in March and November and the lowest in August, which was in contrary to the periodic change of air temperature, precipitation, and other climate factors in this region. The widest spatial distribution of snow cover was in the winter, followed by the autumn and the spring, and the smallest was in the summer. In recent 20 years, the snow cover increased significantly in the winter in eastern and southern QTP, and decreased significantly in the autumn and the spring. The snow cover decreased in the summer in the whole QTP. (4) The correlations between snow cover and air temperature and precipitation were strong. Snow cover had a negative correlation with air temperature and a positive correlation with precipitation. The results of the study are useful for understanding the situation of ice and snow melting water change and are indicative of the regional water balance and climate change of the QTP.