The East Asian monsoon during MIS 2 expressed in a speleothem delta 18O record from Jintanwan Cave, Hunan, China

Stalagmite J1 from Jintanwan Cave, Hunan, China, provides a precisely dated, decadally resolved delta 18O proxy record of paleoclimatic changes associated with the East Asian monsoon from 29.5 to 14.7 ka and from 12.9 to 11.0 ka. At the time of the last glacial maximum (LGM), the East Asian summer monsoon weakened and then strengthened in response to changes in Northern Hemisphere insolation. As the ice sheets retreated the East Asian summer monsoon weakened, especially during Heinrich event H1, when atmospheric and oceanic teleconnections transferred the climatic changes around the North Atlantic to the monsoonal regions of Eastern Asia. A depositional hiatus between 14.7 and 12.9 ka leaves the deglacial record incomplete, but an abrupt shift in delta 18O values at 11.5 ka marks the end of the Younger Dryas and the transition into the Holocene. Comparisons of the J1 record to other Chinese speleothem records indicate synchronous climatic changes throughout monsoonal China. Further comparisons to a speleothem record from western Asia (Socotra Island) and to Greenland ice cores support hemispherical-scale paleoclimatic change. Spectral and wavelet analyses reveal centennial- and decadal-scale periodicities that correspond to solar frequencies and to oscillations in atmospheric and oceanic circulation.