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Abstract: Previous studies show that the area of a moraine-dammed lake can provide a good indicator of the significance of its outburst. For a glacier-dammed lake however, because its area and depth fluctuates with the melting of its ice dam, it is difficult to predict the outburst of the glacier‐dammed lake by using its area alone. A characteristic of the surface of Lake Merzbacher is a large amount of floating ice therefore, a method is proposed in this article to extract the area of floating ice on the lake and the area of ice free water in the lake by using Environment and Disaster Monitoring Small Satellite images respectively. Furthermore, based on the area of floating ice extracted through the image information of Lake Merzbacher in 2009 and 2010, we determined the relationship between the ice area and the outburst of the lake, then formulated the Index for hazard of Glacier Lake Outburst Flood (IGLOF) of Lake Merzbacher, which cannot only predict the flood outburst, but also determine the specific outburst period after the lake drainage had occurred. This can be shown in a recalculation of the lake drainages in the years 2009 and 2010. Research results indicate that when IGLOF is less than 0.5 and the lake area is larger than 3km2, the outburst process is in early-warning period and GLOF will occur in the next 5–8days. Also, the successful outburst prediction of Lake Merzbacher in 2011 showed that the index described in this paper provides a quick methodology for forecasting and warning against Lake Merzbacher outburst floods. However，as our research was based on a short observation period (2009-2011) and also cannot be supplemented by other images, it will still be needed to be checked and validated by continuous observation and improvement in future. [Copyright &y& Elsevier]

Abstract: Aeolian sandy land in the Yarlung Zangbo River basin has attracted the attention of many researchers. However, its dynamics as well as its relevance to various factors has rarely been reported with integrated studies. In this paper, spatio-temporal dynamics of the aeolian sandy land in the basin was studied by interpreting Landsat images acquired from 1975, 1990, 2000, and 2008 with the help of geographic information system (GIS) technology. Spatially, the results showed a decreasing trend from west to east, which is from the Maquanhe wide valley in the headwater area to the middle and lower reaches of the river basin. Temporally, aeolian sandy lands in the basin showed a slow increasing trend, with an increase of 10.5% during the 1975–2008 period, spreading most quickly during the period of 1990–1999. The factors related to dynamics of aeolian sandy land were analyzed from the perspectives of two driving factors, climate changes and human activities. The climate-dominated natural factors are the internal driving forces for the development of aeolian sandy lands, and the human factors are the external driving forces responsible for the increase of the aeolian sandy land area. [Copyright &y& Elsevier]