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The temporal and spatial patterns of late Holocene climate conditions provide valuable information for testing hypothesized mechanisms of recent climate changes. As a proxy for late Holocene climate in the southern tropics, we present a 10 Be chronology of moraines deposited by Qori Kalis, an outlet glacier of Quelccaya Ice Cap in Peru. The Qori Kalis moraines are located downfl ow from the Quelccaya ice cores and provide the fi rst glacial extent record that can be compared directly to annually resolved tropical ice core records. Qori Kalis advanced to its late Holocene maximum extent prior to 520 ± 60 yr before CE 2009, when Quelccaya ice core net accumulation values were at or below their late Holocene average. Subsequent glacial retreat between ~520 and 330 yr before CE 2009 coincides with the highest net accumulation values of the ~1800-yr-long ice core record. Therefore, we suggest that temperature, rather than net accumulation, was the primary driver of these glacial fl uctuations. Comparison of the late Holocene fl uctuations of Qori Kalis glacier with glaciers in the southern tropical Andes, Patagonian Andes, Switzerland, Alaska and New Zealand suggests globally synchronous, centennial-scale cold events.

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Tropical glaciers retreated before deglacial greenhouse gas rise due to a lowered meridional thermal gradient.

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