InterCarto. InterGIS (Jan 2017)
CHANGES IN THICKNESS OF PERETOLCHIN GLACIER (EASTERN SAYAN)
Abstract
For the first time, the ice volume of Peretolchina Glacier in the mountain range of MunkuSardyk (Eastern Sayan) has been estimated using various models and results of georadar profiling. It is advisable to use the averaged values for calculations in accordance with power formulas taking into account the different shape of the glacier bed. Results of area radar survey and ice thickness modeling of Peretolchina Glacier have been presented. Insufficient number of instrumental data on the thickness and volume of the Eastern Sayan glaciers limits the possibility of a correct assessment of regional ice resources. Measurements of the ice thickness on the northern Peretolchin Glacier were carried out in mid-June 2014 and early May 2016 by the Oko-2 radar with the antenna unit ABDL “Triton” at a frequency of 100 MHz. During the field work, profiles of lengths from 100 to 340 m were traversed along the glacier. In total, 8 transverse (1510 m) and one for the 8th, longitudinal (760 m) georadar profiles with a total length of 2270 m. The maximum measured thickness of ice reaches 23 m when interpolated using mathematical models of 37 m. Preliminary maps of ice thickness and profiles of the bed of the northern Peretolchin Glacier have been made and its volume has been determined by different models with field study corrections of 0.007 ± 0.001 km3 . The most accurate results have been obtained from the section method taking into account the relief of the glacier. In the parabolic form of the glacier, a somewhat understated result has been obtained, and an elliptic result has been overestimated. For more than 100 years the Peretolchin Glacier (northern) has decreased in area and length by two times from 0.68 to 0.34 km2 , and in the volume from 0.026 to 0.007 km3 , by 3.7 times. It has been established that the rate of reduction of Peretolchin Glacier was most intensive in 2009-2012.
Keywords
