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Shri Ashtapad Maha Tirth - II
Since our study is limited by chronology, we ascertained the timing of individual glacial stages by comparing the ELA depression estimated from the present study with that of the climatically identical and geographically proximal Nyalam valley-1. The timing of KS-I glaciation is uncertain. However, looking at the ELA depression of - 600 m and associated temperature decline of -4°C, this event is likely to pre-date LGM. A comparable ELA depression (~ 500 m) and the associated temperature decline (-3°C) during KS-II advance compare well with the glacial expansion observed during LGM in Nyalam valley21. Whereas KS-III would correspond to the post-glacial (Holocene?) advance (ELA depression - 200 m and temperature decrease ~1°C). In addition, exposed glaciated bedrock and conical heap of moraines (Figures 3 and 6) probably correspond to recent or sub-recent increase in temperature after LIA (- 19th century AD). Figure 9 is a pictorial depiction of the changes in ice cover since the KS-III glaciation to the Present. This depiction is based on the mapping of lateral moraines associated with KS-III glaciation and the glaciogenic features discussed earlier.
@ Mougt Kailas
500 m Fig.9: Glacier reconstruction based on the lateral moraine associated with KS-III glaciation, push moraine and exposed glaciated bedrock. The observations are superimposed on June 2009 IKONOS data. The reconstructed glacier extents are bordered with yellow dots. Glacier extent during (a) KS-III, (b) deposition of push moraine and glaciated bedrock development and present position.
Our inferences although speculative, provide a broad framework of Late Quaternary glacier history from one of the most ecologically fragile terrains in the Himalaya. The observations presented here indicate that glaciers in southern Kailash region are on a receding trend. At this stage, it is difficult to ascertain if the recession was due to the change in precipitation or temperature. Existing climatic data suggest that compared to the early Holocene, a gradual decline in monsoon was observed in Tibet, particularly after 3 ka. However, the decrease in moisture was not all that low compared to LGM30. Therefore, it can be inferred that after the KS-III glaciation, there would have been a decrease in rainfall around Mount Kailash. However, considering the presentday rainfall of 200 mm, it is not all that low to cause alarming recession of the glaciers. We hypothesize that after the KS-III glaciation, a steady increase in the summer temperature with a
Geomorphic evidence of glaciations around Mount Kailash...
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