The hydrological cycle and ocean circulation of the Maritime Continent in the Pliocene: results from PlioMIP2

• Published in: Climate of the past 2023-10, Vol.19 (10), p.2053-2077
• Main Authors: Ren, Xin, Lunt, Daniel J, Hendy, Erica, von der Heydt, Anna, Abe-Ouchi, Ayako, Otto-Bliesner, Bette, Williams, Charles J. R, Stepanek, Christian, Guo, Chuncheng, Chandan, Deepak, Lohmann, Gerrit, Tindall, Julia C, Sohl, Linda E, Chandler, Mark A, Kageyama, Masa, Baatsen, Michiel L. J, Tan, Ning, Zhang, Qiong, Feng, Ran, Hunter, Stephen, Chan, Wing-Le, Peltier, W. Richard, Li, Xiangyu, Kamae, Youichi, Zhang, Zhongshi, Haywood, Alan M
• Format: Article
• Language: English
• Subjects: Anomalies; Atmosphere; Atmospheric models; Carbon dioxide; Climate; Climate change; Cluster analysis; Continental interfaces, environment; El Nino; Geography; Heat; Hydrologic cycle; Hydrological cycle; Hydrology; Indonesian Throughflow; Intercomparison; Marine transportation; Modelling; Ocean; Ocean circulation; Ocean currents; Ocean, Atmosphere; Oceans; Pliocene; Precipitation; Salinity; Sciences of the Universe; Sea surface; Sea surface temperature; Sea surface temperature anomalies; Shelving; Simulation; Surface salinity; Surface temperature; Temperature anomalies; Volume transport; Water circulation
• ISSN: 1814-9332; 1814-9324; 1814-9332
• DOI: 10.5194/cp-19-2053-2023

The Maritime Continent (MC) forms the western boundary of the tropical Pacific Ocean, and relatively small changes in this region can impact the climate locally and remotely. In the mid-Piacenzian warm period of the Pliocene (mPWP; 3.264 to 3.025 Ma) atmospheric CO.sub.2 concentrations were â¼ 400 ppm, and the subaerial Sunda and Sahul shelves made the land-sea distribution of the MC different to today. Topographic changes and elevated levels of CO.sub.2, combined with other forcings, are therefore expected to have driven a substantial climate signal in the MC region at this time. By using the results from the Pliocene Model Intercomparison Project Phase 2 (PlioMIP2), we study the mean climatic features of the MC in the mPWP and changes in Indonesian Throughflow (ITF) with respect to the preindustrial. Results show a warmer and wetter mPWP climate of the MC and lower sea surface salinity in the surrounding ocean compared with the preindustrial. Furthermore, we quantify the volume transfer through the ITF; although the ITF may be expected to be hindered by the subaerial shelves, 10 out of 15 models show an increased volume transport compared with the preindustrial.