GLACIAL REGIME OF THE HIGHEST TIEN-SHAN MOUNTAIN, POBEDA-KHAN TENGRY MASSIF

Major processes controlling the existence of a large sub-continental g lacier system were identified on the basis of glaciological, meteorolo gical and isotopic analyses using expeditionary and long-term data. Ob servations were made on the southern Inylchek glacier located in the P obeda-Khan Tengry massif, the largest sub-continental glacier system o n the northern periphery of central Asia. More than 1200 glaciers with a total area of about 4320 km(2) comprise the massif. Melt is for the most part caused by radiation and is most intensive during periods of anticyclonic weather with fohn development. The proportion of solar r adiation input in relation to heat balance is more than 90%. Evaporati on and condensation are negligible during most times and comprise 7% o f heat expenditure. Accumulation was associated with cold cyclonic wea ther. Four ice-formation zones were identified, the upper boundary of liquid runoff is at 5200 m and the recrystallization zone is above 590 0 m. The calculated net glacier mass is negative,-318 kg m(-2) a(-1), and indicates the degradation of modern Pobeda-Khan Tengry glaciers.