Holocene glacial deposits in Sredniya Avacha headwaters are subdivided into three age groups (events A, B, and C) based upon geomorphic features, tephrochronology, and lichenometry. Tephras of Opala volcano (1400–1500 yr B.P.), Ksudach volcano (1700–1800 and 6000 yr B.P.), and Zavaritskiy volcano (2800 yr B.P.) are used as stratigraphic markers. Rhizocarpon geographicum (L.) DC and Rhizocarpon section Alpicola growth curves are established using tephrochronologically dated and historical surfaces. The age of event A (pre-Hypsitermal?) moraines is constrained by an age of 6000 yr B.P. for overlying Ksudach-2 tephra and an age of 7200 (?) lichenometric (L) yr B.P. Event B (Neoglaciation) had a multiple nature, with the most prominent advances at 4300–3500, 3300–2800, 2600–2100, 1800–1400, and 1300–1100 (L) yr B.P.; the culmination occurred before 2800 yr B.P., as suggested by a date for Zavaritskiy volcano tephra found on the glacial and outwash deposits. Less-extensive glacier advances of event C (“Little Ice Age”), occurred at 800–600, 500–200, 180–110, and 90–40 (L) yr B.P. The ELA depression was 200–250, 100–150, 30–70 m during the culmination of events A, B, and C, respectively.
Evidence for the timing and extent of late-Holocene glacial advances in the Tian Shan mountains, central Asia, is based on lichenometric and radiocarbon dating of end-moraines. Three phases of glacial advance occurred at 1700-2100 and 1100-1300 lichenometric (L) years ago, and then during the 'Little Ice Age', 150- 700 (L) years ago. Differences in the pattern of glacier variations between the northwestern frontal and inner areas of the Tian Shan are reflected in the equilibrium line altitude (ELA) depression of 23 glaciers studied at nine selected sites. The peripheral glaciers appear to have been significantly more extensive during late- Holocene advances than the glaciers of the inner areas. This difference seems to be explained by regional differences in humidification: in the northwestern periphery of the Tian Shan, the cold periods of the late Holocene were more humid than the warm period of the mid-Holocene; whereas, in the inner areas, the pattern of climate changes was the opposite (a warm and humid mid-Holocene was followed by a cold and arid late Holocene).
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This paper presents a comprehensive assessment of the water storage properties of glaciers and seasonal snow, carried out for the first time at a major river basin scale, for the Indus, Ganges, Brahmaputra, Amu Darya, Syr Darya and Mekong basins. It analyzes the changes of glaciers and snow under recent climate change, i.e., between the baseline (1961-1990) and current (2001-2010) periods. The paper also addresses climate change sensitivity of glacier systems and the changes that might be expected under a warming scenario for the end of the twenty-first century
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