Variations of Primary Productivity in the Northwestern Arabian Sea During the Last 23,000 Years and Their Paleoclimatological Implications

• Published in: Paleoceanography and Paleoclimatology
• Main Authors: Zhou, Xinquan, Duchamp-Alphonse, Stéphanie, Kageyama, Masa, Bassinot, Franck, Doressoundiram, Florian, Kissel, Catherine
• Other Authors: South China University of Technology Guangzhou (SCUT), Géosciences Paris Saclay (GEOPS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Modélisation du climat (CLIM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Climat et Magnétisme (CLIMAG)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2022
• Subjects: [SDE]Environmental Sciences; Ice Sheet
• Online Access: https://hal.science/hal-03874269; https://hal.science/hal-03874269/document; https://hal.science/hal-03874269/file/Paleoceanog%20and%20Paleoclimatol%20-%202022%20-%20Zhou%20-%20Variations%20of%20Primary%20Productivity%20in%20the%20Northwestern%20Arabian%20Sea%20During%20the.pdf; https://doi.org/10.1029/2022PA004453

International audience Abstract Despite tectonic conditions and atmospheric CO 2 levels ( pCO 2 ) similar to those of present-day, geological reconstructions from the mid-Pliocene (3.3-3.0 Ma) document high lake levels in the Sahel and mesic conditions in subtropical Eurasia, suggesting drastic reorganizations of subtropical terrestrial hydroclimate during this interval. Here, using a compilation of proxy data and multi-model paleoclimate simulations, we show that the mid-Pliocene hydroclimate state is not driven by direct CO 2 radiative forcing but by a loss of northern high-latitude ice sheets and continental greening. These ice sheet and vegetation changes are long-term Earth system feedbacks to elevated pCO 2 . Further, the moist conditions in the Sahel and subtropical Eurasia during the mid-Pliocene are a product of enhanced tropospheric humidity and a stationary wave response to the surface warming pattern, which varies strongly with land cover changes. These findings highlight the potential for amplified terrestrial hydroclimate responses over long timescales to a sustained CO 2 forcing.