Zhimin Jian1*, Yue Wang1*, Haowen Dang1*, Mahyar Mohtadi2 , Yair Rosenthal3,4, David W. Lea5 , Zhongfang Liu1 , Haiyan Jin1 , Liming Ye6 , Wolfgang Kuhnt7 & Xingxing Wang1
1 State Key Laboratory of Marine Geology, Tongji University, Shanghai, China.
2 MARUM-Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany.
3 Department of Marine and Coastal Science, Rutgers University, New Brunswick, NJ, USA.
4 Department of Earth and Planetary Sciences, Rutgers University, New Brunswick, NJ, USA.
5 Department of Earth Science, University of California, Santa Barbara, CA, USA.
6 Second Institute of Oceanography, Ministry of Natural Resource, Hangzhou, China.
7 Institute of Geosciences, Christian-Albrechts-Universität, Kiel, Germany.
Abstract：
The Indo-Pacifc Warm Pool (IPWP) exerts a dominant role in global climate by releasing huge amounts of water vapour and latent heat to the atmosphere and modulating upper ocean heat content (OHC), which has been implicated in modern climate change1 . The long-term variations of IPWP OHC and their efect on monsoonal hydroclimate are, however, not fully explored. Here, by combining geochemical proxies and transient climate simulations, we show that changes of IPWP upper (0–200 m) OHC over the past 360,000 years exhibit dominant precession and weaker obliquity cycles and follow changes in meridional insolation gradients, and that only 30%–40% of the deglacial increases are related to changes in ice volume. On the precessional band, higher upper OHC correlates with oxygen isotope enrichments in IPWP surface water and concomitant depletion in East Asian precipitation as recorded in Chinese speleothems. Using an isotope-enabled air–sea coupled model, we suggest that on precessional timescales, variations in IPWP upper OHC, more than surface temperature, act to amplify the ocean–continent hydrological cycle via the convergence of moisture and latent heat. From an energetic viewpoint, the coupling of upper OHC and monsoon variations, both coordinated by insolation changes on orbital timescales, is critical for regulating the global hydroclimate.
Full Article：https://www.nature.com/articles/s41586-022-05302-y
