Almost a century ago, fears began to be expressed about the possible impact of the rise in atmospheric temperature on mountain glaciers. The fears led to the initiation of concerted scientific efforts to identify and examine the fluctuations along the front-snout of glaciers. It was believed that such studies, over the next century or so, would enable scientists to establish the relationship between the climate change and the glacier fluctuations.
Monitoring of a glacier, in specific terminology, means the study of glacier growth or degeneration over a specific period of time, laterally, vertically and in its longitudinal profile. Monitoring of glaciers, sensu stricto, is restricted to the study of the glacier snout, i.e., the front end of the glacier. The general belief is that the snout or the lowest extremity of a glacier reflects its health. A glacier in the Himalayas, on average, moves downward at a daily rate of one to three cm along the lower limits. It was the general belief of early glaciologists that the snout, in certain respects, denoted the altitudinal level where the melting of the glacier ice caused by the increased temperature of lower altitudes balanced the glacier’s downward movement. It was believed that the position of a glacier snout would undergo change - both in altitude and appearance - with changes in temperature and snow precipitation. Later studies have revealed that in reality things do not pan out that way. The regional and the local geomorphic features have been observed to have as much influence in the glacier snout fluctuations as the climatic parameters.
