Journal
PALEOCEANOGRAPHY AND PALEOCLIMATOLOGY
Volume 35, Issue 12, Pages -Publisher
AMER GEOPHYSICAL UNION
DOI: 10.1029/2020PA003985
Keywords
leaf wax; water isotopes; Indo‐ Pacific Warm Pool; Pleistocene; proxy‐ model comparison
Funding
- David and Lucile Packard Foundation Fellowship in Science and Engineering
- National Science Foundation Graduate Research Fellowship Program [DGE-1746060]
- Heising-Simons Foundation [2016-015]
Ask authors/readers for more resources
The Indo-Pacific Warm Pool (IPWP) is home to the warmest sea surface temperatures in the world oceans, favoring strong tropospheric convection and heavy rainfall. The mechanisms controlling long-term change in the region's hydroclimate are still uncertain. Here, we present a 450,000-year record of precipitation delta D from southern Sumatra that records a consistent pattern of glacial isotopic enrichment and interglacial depletion. We synthesize existing paleo-indicators of precipitation delta D and delta O-18 in the IPWP and compare results with water isotope-enabled climate simulations of the Last Glacial Maximum (LGM). The simulations show glacial isotopic enrichment over the eastern Indian Ocean extending into the southern IPWP and isotopic depletion over Southeast Asia, the west Pacific, and Australia. The pattern of simulated LGM isotopic change agrees generally well with our proxy synthesis. We conclude that reorganization of regional circulation under glacial conditions controls precipitation isotope variability in the IPWP: Low-level tropospheric convergence dominates the signal in the north/east, whereas divergence controls the response in the south/west. Additional sensitivity simulations suggest that the LGM ice sheets and the associated lowering in sea level, rather than decreased greenhouse gases, are responsible for the distinctive spatial pattern in glacial changes of precipitation isotopes and hydroclimate across the IPWP.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available