Late-Holocene glacier variations in the frontal and inner ranges of the Tian Shan, central Asia

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 bi tween 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).