Glacier fluctuations and climate


       

Regular studies of Tien Shan glaciers begun in  1948, when Then Shan Geographical Research Station in Porkovka (Issik-Kul  district) was established. In 1980s L.R. Serebryanny and his team (Serebryanny  et al., 1989, Solomina, 1996, 1999 etc.) studied Holocene moraine morphology,  chronology, and geomorphic processes. They found out that the climate warming  in Tien Shan started ca. 12-9 kyr B.P., continued in the early Holocene and  culminated in the middle Holocene. Humidity was low during the mid Holocene.  Glaciers retreated up to modern size about 8000-9000 years ago. In the Late  Holocene three cold stages were identified by pollen analysis and numerous  glacier advances were dated by lichenometry. 14C dating of peat bogs and buried  soils bring evidences of glacier retreat ca 6000 and 1000 years ago. "Medieval  Warm Period" occurred in the Tien Shan in 7-14 centuries. Its peak was in 10 century with increased  temperature and reduced humidity. Most of lichenometrically dated Little Ice  Age moraines were deposited in 17 and 19 centuries. They overlay in most cases  the earlier moraines of 8-15 centuries.       

Tien Shan glaciers advanced in 1850th, 1880th and first and second decades of  20th century according to historical data. The retreat of Tien Shan glaciers from their  Little Ice Age maximum extent was estimated using aerial photographs from 1980  to 1985 and maps (1956-1990s). Historical information (since 1880s) was used as  indirect control of remote sensing data. The age of moraines in key regions was  estimated by lichenometry. On average Tien   Shan glaciers have retreated by  989+/-540m, their elevation rose by 151+/-105 m. (Solomina, Barry, and Bodnya,  2004).       

Bibliography       

Serebryanniy, L.R., Orlov, A.V., Solomina, O.N., 1989. Moraines as a source of glaciological information. Moscow, Nauka Press, 236 pp. (in Russian with English summary)       

Savoskul, O. S., Solomina, O.N. (1996). "Late-Holocene glacier variations in the frontal and inner ranges of the Tian Shan, Central Asia. " 61:25-35.       

Solomina O.N., 1999. Mountain glaciation of Northern Eurasia in the Holocene. – Moscow, Scientific World Press, 272 pp. (in Russian with English summary)       

Solomina O.N., 1996. Long-term variations of mountain glaciers in the former USSR (FSU). Part 2. Dendrochronology and licenometry. – Zeitschrift für Gletcherkunde und Glazialgeologie, Vol. 32, pp. 197-205.       

Solomina O.N., Savoskul O.S., Cherkinsky A.E., 1994. Glacier variations, mudflow activity and landscape development in the Aksay Valley (Tian Shan) during the Holocene. – The Holocene, Vol. 4, No. 1, pp. 25-31. (PDF)       

Solomina, O., Barry, R., Bodnya, M. (2004). "The retreat  of Tien Shan glaciers (Kyrgyzstan) since the Little Ice Age estimated from aerial photographs, lichenometric and historical data." Geographiska Annaler 86A(2): 205-215.


← back