• A coherent response of Southern Indian Ocean to the Antarctic climate: Implications to the lead, lags of atmospheric CO$_{2}$ during deglaciation

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      https://www.ias.ac.in/article/fulltext/jess/129/0214

    • Keywords

       

      Southern Ocean; Antarctic climate; atmospheric CO$_{2}$; $\delta^{18}$O records; deglaciation.

    • Abstract

       

      A record of $\delta^{18}$Oc from the Indian sector of Southern Ocean and atmospheric CO$_{2}$, and $\delta^{18}$O of European Project for Ice Coring in Antarctica (EPICA) and Greenland Ice Sheet Project 2 (GISP2) reveals that a coherent response between $\delta^{18}$O record of Antarctic ice core and the $\delta^{18}$Oc record from Southern Indian Ocean during the deglaciation with initial warming starting around 18 kyr BP which is in agreement with the raise of atmospheric CO$_{2}$ during same time. A distinct asynchrony between the records of $\delta^{18}$Oc from the Southern Indian Ocean and $\delta^{18}$O of GISP2 during the last deglaciation is noticed. We report that Southern Ocean degassing played an important role in raising atmospheric CO$_{2}$ through Atlantic Meridional Overturning Circulation (AMOC), which has an implication in triggering abrupt climate events through coupling of ocean and atmospheric processes.

      $\bf{Highlights}$

      $\bullet$ A synchrony between the temperature variations between the Antarctica and the southern sector of the Indian Ocean are noticed during the deglaciation.

      $\bullet$ Initiation of deglacial warming in the southern sector of Indian Ocean started around 18 Ka which coincides with rise of atmospheric CO$_{2}$ during the same time.

      $\bullet$ Degassing in the Southern Ocean played an important role in raising atmospheric CO$_{2}$ during the deglaciation.

      $\bullet$ Changes in AMOC variations contributed to the trigger of CO$_{2}$ degassing from the deep Southern Ocean.

    • Author Affiliations

       

      NARAYANA A C1 P DIVAKAR NAIDU2 BHAVANI P G1 MASOOD AHMAD3

      1. Centre for Earth, Ocean and Atmospheric Sciences, University of Hyderabad, Hyderabad 500 046, India.
      2. CSIR-National Institute of Oceanography, Dona Paula, Goa 403 002, India.
      3. Formerly CSIR-National Geophysical Research Institute, Hyderabad 500 007, India.
    • Dates

       
  • Journal of Earth System Science | News

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