TY - JOUR T1 - Deglacial ?18O and hydrologic variability in the tropical Pacific and Indian Oceans JF - Earth and Planetary Science Letters Y1 - 2014 A1 - Gibbons, Fern T. A1 - Oppo, Delia W. A1 - Mohtadi, Mahyar A1 - Rosenthal, Yair A1 - Cheng, Jun A1 - Liu, Zhengyu A1 - Linsley, Braddock K. KW - Deglaciation KW - Eastern Equatorial Pacific KW - heat transport KW - Indo-Pacific KW - δ18O of seawater AB - Evidence from geologic archives suggests that there were large changes in the tropical hydrologic cycle associated with the two prominent northern hemisphere deglacial cooling events, Heinrich Stadial 1 (HS1; ∼19 to 15 kyr BP; kyr BP = 1000 yr before present) and the Younger Dryas (∼12.9 to 11.7 kyr BP). These hydrologic shifts have been alternatively attributed to high and low latitude origin. Here, we present a new record of hydrologic variability based on planktic foraminifera-derived δ18O of seawater (δ18Osw) estimates from a sediment core from the tropical Eastern Indian Ocean, and using 12 additional δ18Osw records, construct a single record of the dominant mode of tropical Eastern Equatorial Pacific and Indo-Pacific Warm Pool (IPWP) hydrologic variability. We show that deglacial hydrologic shifts parallel variations in the reconstructed interhemispheric temperature gradient, suggesting a strong response to variations in the Atlantic Meridional Overturning Circulation and the attendant heat redistribution. A transient model simulation of the last deglaciation suggests that hydrologic changes, including a southward shift in the Intertropical Convergence Zone (ITCZ) which likely occurred during these northern hemisphere cold events, coupled with oceanic advection and mixing, resulted in increased salinity in the Indonesian region of the IPWP and the eastern tropical Pacific, which is recorded by the δ18Osw proxy. Based on our observations and modeling results we suggest the interhemispheric temperature gradient directly controls the tropical hydrologic cycle on these time scales, which in turn mediates poleward atmospheric heat transport. VL - 387 UR - https://doi.org/10.1016/j.epsl.2013.11.032 ER -