On the recent rapid deterioration of Himalayan cryosphere

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For examining the cause of the recent deterioration of Himalayan cryosphere, an ice core retrieved in Hidden Valley was analyzed for the concentration of various ions, insoluble particles, tritium and amino-acid. The results for amino-acid concentration indicated that its concentration can be an indicator of the biotic activities, which could be used for ice core dating by counting the annual cycles of the amino-acid concentration. The analysis of the concentration of optical isomers showed that the increase of L-isomer takes place in situ by the biotic activities, and it decreases with time toward the thermodynamic equilibrium state : gradual increase of D-isomer. This can be utilized to date the core independently.Snow pit observation has been carried out at Moshiri, Hokkaido in order to understand the evolution of some parameters in a wet snow pack, for interpreting the core data. The particle size increased more rapidly in a wet snow pack than in dry state. The change of stable isotope ratio in a wet snow pack was expressed in terms of the phase change in association with the grain growth of snow particles.Heat budget analysis was carried out for supraglacial ice cliffs and ponds, which are very important for the mass balance of debris-covered glaciers. It was found that the rate of melting at ice cliffs are roughly 70 times larger than the average rate of melting in debris-covered area, and the contribution of melting at ice cliffs is very significant for shrinkage of glaciers. Also, the warmed water in ponds would contribute significantly to melt the ice surrounding water channels through which the water leaks.Dendro-chronological analysis was also made with samples collected at Daulagiri Valley and Shorong Valley, Nepal.Two volumes of data report have been published for internal use of the data obtained. At the same time, a leaflet, in English as well as in Nepalese, explaining the results and findings of this project for general people, and distributed.