The evolution of surging glaciers of the Pamirs, central Asia, has been studied using repeat remote-sensing surveys in the Institute of Geography, Russian Academy of Sciences, since the early 1970s. We use images obtained from national Resurs-F satellites (1972–91), as well as Landsat 7 and Terra (1999–2006), to provide a basis for monitoring of surging glaciers, aimed at developing their inventory, studying the causes and mechanisms of surges and examining the timing and extent of glacial catastrophes. The inventory from the early 1990s allows identification of 215 glaciers with a dynamically unstable regime. We discovered 51 surging glaciers. Up until 2006, 10 more surges had occurred. We use stereoscopic deciphering and photogrammetric processing of consecutive satellite images to study the morphology and ice-velocity changes of several compound surging glaciers. We analyze the results of monitoring of Bivachny and Oktyabr’sky glaciers from 1972 to 1991 and Sugran glacier from 1972 to 2006. Two surges of Sugran glacier occurred during this time: an internal surge in 1976–80, and a surge with glacier tongue advance as far as 4.5 km in 2000–05. The role of damming in compound glacier systems is examined. Satellite-based monitoring is now the only method for obtaining initial information about the state and fluctuations of such glaciers.

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The paper describes the characteristics and behavior of unstable glaciers in the Pamirs, central Asia, over the last 30 years. These glaciers are divided into three groups: glaciers with registered surges; glaciers with signs of current instability; glaciers with signs of instability in the recent past. Examples are given to illustrate the nature of glacier fluctuations at a time of general glacier retreat in the Pamirs. A description is given of the evolution of Medvezhiy surging glacier, which was the subject of detailed annual observation from 1963 to 1991. Comparative characteristics of two building-up stages of this glacier, 1964–72 and 1974–88, are produced. On the basis of aerotopographic monitoring and with the aid of computer analysis, the kinematics of the glacier surface during the 1988–89 surge are traced in detail and the role of microsurges in the course of glacier build-up and the glacier surge is established.

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The paper describes the characteristics and behavior of unstable glaciers in the Pamirs, central Asia, over the last 30 years. These glaciers are divided into three groups: glaciers with registered surges; glaciers with signs of current instability; glaciers with signs of instability in the recent past. Examples are given to illustrate the nature of glacier fluctuations at a time of general glacier retreat in the Pamirs. A description is given of the evolution of Medvezhiy surging glacier, which was the subject of detailed annual observation from 1963 to 1991. Comparative characteristics of two building-up stages of this glacier, 1964–72 and 1974–88, are produced. On the basis of aerotopographic monitoring and with the aid of computer analysis, the kinematics of the glacier surface during the 1988–89 surge are traced in detail and the role of microsurges in the course of glacier build-up and the glacier surge is established.