14 Oct 2022
14 Oct 2022
Status: this preprint is open for discussion.

Seasonal to interannual variabilities of sea–air CO2 exchange across Tropical Maritime Continent indicated by eddy–permitting coupled OGCM experiment

Faisal Amri1, Takashi Nakamura1, Atsushi Watanabe2, Aditiya R. Kartadikaria3, and Kazuo Nadaoka1 Faisal Amri et al.
  • 1Transdisciplinary Science and Engineering Department, Tokyo Institute of Technology, Tokyo, Japan
  • 2Ocean Policy Research Institute, The Sasakawa Peace Foundation, Japan
  • 3Faculty of Earth Sciences and Technology, Oceanography Research Group, Institut Teknologi Bandung, Bandung, Indonesia

Abstract. The lack of long–term observational data has limited research on sea–air CO2 exchange variabilities in the Tropical Maritime Continent (TMC). To address the issue, we utilized a three–dimensional high–resolution physical–biogeochemical ocean numerical model and applied it to simulate sea–air CO2 exchange in the region over the last decade (2010–2019). Some key features like atmospheric CO2 source signature and high sea surface pCO2 environment inside the TMC were captured by the model. Within the TMC, model results indicated strong CO2 degassing along the south of Java associated with the seasonal cycle of the upwelling system. Abundant supply of inorganic carbon during upwelling season and strong wind speed results in CO2 degassing that could reach as high as 30 gC m–2 year–1 around the area. In addition to the region acting as a full–year atmospheric CO2 source, the TMC also exhibited interannual modulation in both sea–air CO2 flux and sea surface pCO2 which can be related to the El Niño–Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD). Large–scale anomalous strong CO2 degassing and high sea surface pCO2 from 2015 to 2016 in response to the 2015/2016 El Niño evolution was observed and dominated by modulation within the TMC. It is further found that modulation of CO2 degassing related to IOD were confined along the west of south of Java with a higher magnitude compared with anomalies related to ENSO which shows larger spatial scale but lower in the magnitude. Study conducted here may provide insight about possible variabilities of sea–air CO2 exchange in the area that still poorly represented in many global–scale modelling and reconstruction efforts.

Faisal Amri et al.

Status: open (until 09 Dec 2022)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on egusphere-2022-1067', Anonymous Referee #1, 28 Nov 2022 reply
  • RC2: 'Comment on egusphere-2022-1067', Anonymous Referee #2, 28 Nov 2022 reply
    • AC1: 'Reply on RC2', Faisal Amri, 06 Dec 2022 reply

Faisal Amri et al.

Data sets

Annual global-averaged atmosphere’s CO2 concentration ESRL NOAA

Model code and software

Original model code and necessary tools to prepare the input for simulation experiment Takashi Nakamura

Faisal Amri et al.


Total article views: 223 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
162 52 9 223 21 1 1
  • HTML: 162
  • PDF: 52
  • XML: 9
  • Total: 223
  • Supplement: 21
  • BibTeX: 1
  • EndNote: 1
Views and downloads (calculated since 14 Oct 2022)
Cumulative views and downloads (calculated since 14 Oct 2022)

Viewed (geographical distribution)

Total article views: 207 (including HTML, PDF, and XML) Thereof 207 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
Latest update: 06 Dec 2022
Short summary
This study investigates the sea-air CO2 exchange variabilities across the Tropical Maritime Continent between 2010–2019 using numerical model experiment. Model results suggested some periods with higher-than-usual CO2 degassing to the atmosphere related to Indo-Pacific climatic events over the 2010–2019 course. Study conducted here may give insights about sea-air CO2 exchange dynamics in the undersampled area that poorly represented in many climate models and global reconstruction product.