Deglacial Asian monsoon

How to interpret the speleothem water isotope in Asian Monsoon regions?

Monsoons, which are characterized by distinct wet and dry seasons and a seasonal reversal of prevailing winds, are a planet-scale atmospheric phenomenon that affects nearly two-thirds of the world’s population. My research is to improve our understanding of monsoon dynamics and future projections by investigating past changes in global monsoon variability. I focus on the following questions: (1) How does the global monsoon respond to external forcings, such as greenhouse gases, ice sheets, changes in Earth’s orbit, vegetation, and aerosols? (2) How can we interpret associated paleoclimate proxies (e.g., speleothem \(\delta ^{18}O\)) from the past?

I conducted the first set of isotope-enabled transient climate experiments (iTRACE) during the last deglaciation (20,000-11,000 years ago) using a state-of-the-science isotope-enabled Community Earth System Model (iCESM) (He et al., 2021, Sci. Adv.). This was the first time that the deglacial water isotope and hydroclimate evolution in the Asian summer monsoon was quantitatively reproduced in simulation. The success of my simulation shows the deglacial water isotope in Asian monsoon system was driven by water source in the upstream Indian Ocean, while the rainfalls in different regions were regulated by local atmopsheric circulations. This provides a possible solution to reconcile the water isotope-hydroclimate paradox in the Asian monsoon — a longstanding grand challenge in paleoclimate. Another follow-up study (He et al., 2021, Nat. Commun.), for the first time, emphasized the importance of the Autumn monsoon in shaping the deglacial East Asian hydroclimate and has stimulated follow-up studies.



Publications

Journal Articles

  1. JCLI
    Dipole Response of Millennial Variability in Tropical South American Precipitation and δ18 O p During the Last Deglaciation: Part I: Rainfall Response
    Yuntao Bao, Zhengyu Liu, and  Chengfei He
    Journal of Climate, 2023
  2. JCLI
    Dipole Response of Millennial Variability in Tropical South American Precipitation and δ18 O p During the Last Deglaciation: Part II: δ18 O p response
    Yuntao Bao, Zhengyu Liu, and  Chengfei He
    Journal of Climate, 2023
  3. GRL
    Termination 1 Millennial-scale Rainfall Events over the Sunda Shelf
    F Buckingham, SA Carolin, JW Partin, JF Adkins, KM Cobb, CC Day, Q Ding,  Chengfei He, and  others
    Geophysical Research Letters, 2022
  4. GRL
    Local Insolation Drives Afro-Asian Monsoon at Orbital-Scale in Holocene
    Qin Wen, Zhengyu Liu, Jiang Zhu, Mi Yan,  Chengfei He, Jing Han, Jian Liu, and Yishuang Liang
    Geophysical Research Letters, 2022
  5. speleo2_large.jpg
    Hydroclimate footprint of pan-Asian monsoon water isotope during the last deglaciation
    Chengfei He, Zhenyu Liu, BL Otto-Bliesner, EC Brady, C Zhu, R Tomas, PU Clark, J Zhu, A Jahn, S Gu, and  others
    Science Advances, 2021
  6. Deglacial variability of South China hydroclimate heavily contributed by autumn rainfall
    Chengfei He, Zhengyu Liu, Bette L Otto-Bliesner, Esther C Brady, Chenyu Zhu, Robert Tomas, Sifan Gu, Jing Han, and Yishuai Jin
    Nature communications, 2021
  7. QSR
    Deglacial trends in Indo-Pacific warm pool hydroclimate in an isotope-enabled Earth system model and implications for isotope-based paleoclimate reconstructions
    Xiaojing Du, James M Russell, Zhengyu Liu, Bette L Otto-Bliesner, Yu Gao, Chenyu Zhu, Delia W Oppo, Mahyar Mohtadi, Yan Yan, Valier V Galy, and  Chengfei He
    Quaternary Science Reviews, 2021
  8. QSR
    A mechanistic understanding of oxygen isotopic changes in the Western United States at the Last Glacial Maximum
    Clay Tabor, Marcus Lofverstrom, Jessica Oster, Barbara Wortham, Cameron Wet, Isabel Montañez, Alan Rhoades, Colin Zarzycki,  Chengfei He, and  others
    Quaternary Science Reviews, 2021