The relationship between the historical glacier fluctuation and the outburst flood of glacier-dammed lakes was analyzed at Hunza Valley in the Karakoram Mountains, Pakistan. As a result, glaciers such as Batura, Pasu, Ghulkin, Hasanabad, Minapin, Ghulmet and Biafo have repeated glacier progressions of about 10Ò20 years after long retreat periods (1860-1907, 1913-1960 and 1980- ) since AD 1860. In addition, it is thought from the growing environment of Jeniperus distributing in the Valley that temperate periods (1865-1895, 1915 -1950 and 1975-1995) appeared in the 20-25 year cycle repeatedly. A relationship between the glacier fluctuation and such climatic condition shows that the glaciers accompanied with a response time of 10-12 years have sensitively responded to climatic changes in the Valley. While, six periods of the outburst flood in Hunza and Shimshal valleys, which appeared in the about 20 year cycle correspond to the retreat periods of the glaciers. It shows that the glacier retreat depending on climatic warming is the trigger of the outburst flood of glacier-dammed lakes, which is preceding the increasing of the melting ice and the expansion of lake area.
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