Thresholds in east asian marginal seas circulation due to deglacial sea level rise

Thresholds in east asian marginal seas circulation due to deglacial sea level rise

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ABSTRACT East Asian marginal seas (EAMS) circulation is closely configurated by sea level rise during the last deglaciation. Here, we perform simulations to reconstruct the EAMS circulation


on the basis of sea levels from −90 to 0 m of the present, using a high-resolution regional ocean circulation model under present-day fixed surface and lateral boundary conditions. Our


results show that the EAMS circulation underwent twice abrupt changes: a rapid initiation of its modern structure when sea level rise exceeded −40 m, followed by a temporary overshoot of the


Japan-Sea throughflows at −5 m. These nonlinear processes are caused by the opening of the Soya Strait and thus formation of the modern EAMS-circulation structure, and a transient absence


of the circulation resembling a Kuroshio Large Meander following around-island integral constraint, respectively. Conceptually, our findings introduce the around-island integral constraint


on abrupt shift in the global marginal-sea circulation during the last deglaciation. SIMILAR CONTENT BEING VIEWED BY OTHERS A PROCESS-BASED ASSESSMENT OF THE SEA-LEVEL RISE IN THE


NORTHWESTERN PACIFIC MARGINAL SEAS Article Open access 26 August 2023 DELAYED ANTARCTIC SEA-ICE DECLINE IN HIGH-RESOLUTION CLIMATE CHANGE SIMULATIONS Article Open access 02 February 2022


SEA-ICE RETREAT SUGGESTS RE-ORGANIZATION OF WATER MASS TRANSFORMATION IN THE NORDIC AND BARENTS SEAS Article Open access 10 January 2022 INTRODUCTION Extraordinary rise of sea level is a


most challenging climatic effect, as a consequence of the on-going global warming1,2,3. According to paleoceanographic evidences, sea level was even higher than the modern condition by a few


meters during the last interglacial (~ 130–115 ka BP), as a heritage of naturally deglacial sea level rise4,5. On the glacial-interglacial time scales, the global ocean has tempered the


effect of sea level oscillations by over 100 m4, in particular for the marginal seas via the processes of land-sea evolution. This is a typical circumstance for the development of


circulation in the East Asian marginal seas (EAMS, one of globally largest marginal-sea region) since the last deglaciation (Fig. 1 and Supplementary fig. 1). Although studies have linked


the deglacial evolution in the EAMS circulation to the coeval climatic processes of e.g., Asian Monsoons6,7,8 and the Kuroshio Current system9,10,11, the impact of changing bathymetry and


the corresponding land-sea masks on the circulation remains unresolved. In this study, we hypothesize the existence of abrupt-change points in the relationship between sea levels and the


EAMS circulation, leading to nonlinear evolution in the EAMS circulation from the last deglaciation to the present, based on modelling simulations and intercomparison with existing


paleoceanographic evidences. Note that here we only test how the changes in sea level and the associated opening of certain key straits would affect the EASM, thus we applied fixed


present-day surface and lateral boundary conditions. RESULTS AND DISCUSSION MODELLED EAMS CIRCULATIONS BASED ON DIFFERENT SEA LEVELS Our modelling results show abrupt change in the EAMS


circulation two times: when sea level rises beyond −40 and −5 m (Fig. 2a–d). Once the sea level becomes higher than −40 m, the Soya Strait opens as an oceanic gateway, and triggers the


formation of the so-called ‘Taiwan-Tsushima-Tsugaru & Soya’ (3T-S) circulation system in the modern ocean12,13 (Fig. 1c and Supplementary figs. 2, 3). Specifically, on the basis of the


open Soya Strait and the established 3T-S circulation system, the Kuroshio Current water also enters the EAMS via the Taiwan Strait besides via the deep-ocean channel east of Taiwan Island.


Then, the Taiwan-Strait throughflow continuously extends northward in the EAMS and reaches the TKS, activating a TKS throughflow into the Sea of Japan. In the meantime, the water export from


the Sea of Japan to the North Pacific Ocean via the Tsugaru Strait is also initialized. Therefore, our modelling results suggest that the sea level rise across −40 m exists as an


abrupt-change point in the relationship between sea level rise and the EAMS circulation evolution since the last deglacition by opening the Soya Strait in a classic ‘ocean-gateway effect’14.


Along further sea level rise from −40 to 0 m, the EAMS circulation becomes stronger generally in an almost continuous manner (Fig. 2a–d). Here, this constitutes an invigoration process in


the EAMS circulation, linked to the widening and deepening of the Taiwan Strait along the sea level rise. It thus results in the development of the Taiwan-Strait throughflow and also its


downstream including the throughflows via the TKS, Tsugaru Strait and Soya Strait, in the form of an intensifying ‘ocean-gateway effect’ at the Taiwan Strait (Fig. 2a). Notably, the


overflows between the Sea of Japan and the North Pacific Ocean, including the throughflows via the TKS, Tsugaru Strait and Soya Strait, commonly exhibit a prominent, surprising overshoot


towards the end of our simulated deglacial sea level rise, at around −5 m sea level (Figs. 2 and 3). According to our modelling results, a replacement of the Kuroshio Large-Meander15,16 like


(KLM-like) circulation to a relatively straighter current along the southeastern coast of Japan (Fig. 3). Such shift from KLM-like flow to the along-shore current virtually occured as an


acceleration in the along-shore current at the southern coast of Japan. Following the around-island integral constraint within the ‘Island rule’ theory17,18 with respect to the Islands of


Japan, the TKS throughflow at the coast of the other side, i.e., the northern side, thus intensified, as the response (Fig. 3 and Supplementary fig. 5). Here, our modelling results are also


in line with paleoceanographic evidence for the onset of an overshoot in the TKS throughflow at about −5 m sea level19 (Fig. 2g). Overall, at around −5 m sea level, on top of the


continuously growing ‘ocean-gateway effect’ with deglacial sea level rise from −40 to 0 m, the transient appearance of the around-island integral constraint triggers the temporary overshoot


in the TKS throughflow into the Sea of Japan. Likewise, because of the necessity to maintain mass-balance, the outflows via the Tsugaru Strait and Soya Strait from the Sea of Japan to the


North Pacific also present an overshoot (Fig. 2b–d). This process thereby constitutes a maximum in circulation intensity through the EAMS within the Holocene. Importantly, in the modelling


experiment of −5 m sea level, the along-shore current in the Pacific south to the Japan Islands is characterised by a quasi-stationary field of eddies with dual cores (Fig. 3). This is


distinct from the prevailing condition of a triple-core, quasi-stationary eddy field, coherent with the KLM-like circulation in the simulations with sea levels between -90 and 0 m. Based on


similar variability in the modern ocean circulation, albeit on shorter time scales, previous physical oceanographic studies16,20 have assigned such changes in the western North Pacific


quasi-stationary eddy configuration as a cause for the shift from the KLM to the along-shore current setting. Here, our modelling results, in line with paleoceanographic reconstructions19,


provide evidence for the hypothesis that a −5 m sea level with a corresponding land-sea mask enables the condition for the existence of quasi-stationary eddies with dual cores, in tandem


with the presence of a linear, along-shore Kuroshio Current system at the southern coast of Japan. Then, the actually acclerated along-shore current at the southern coast of Japan leads to


the occurrence of overshoot intensity in the TKS throughflow, following the around-island integral constraint. INTERCOMPARISON WITH PALEOCEANOGRAPHIC EVIDENCES On the basis of radiolarian


species assembleges from a core near the Tsushima-Korea Strait (TKS) in the southern Sea of Japan, a recent study21 illustrates that the TKS throughflow started to increase from near-absence


after 10 ka BP, before it decreases again from 7 to 0 ka BP (Fig. 2f and Supplementary fig. 7). Once transferred to sea level development between 14 and 0 ka BP22, this indicates an


initiation of the TKS throughflow since sea levels higher than −40 m, and a continuous strengthening along sea level rise from −40 to −5 m, followed by a weakening from −5 m sea level to the


present (Fig. 2i). This timeline of development hence supports our modelling results and inferences about the nonlinear response of the TKS throughflow to sea level rise (Fig. 2b).


Moreover, our modelling results are broadly consistent with other paleoceanographic evidence. In the southern EAMS, multi-proxy reconstructions have used to suggest a rapid development of


maximum circulation intensification north of the Taiwan Island after the early Holocene23. According to our results, this pattern can be attributed to rapid establishment of the Taiwan


Strait throughflow, as a part of the modern-shape 3T-S circulation system (Fig. 2). In addition, a compilation of phytoplankton biomarker contents indicates stronger impact of the Kuroshio


Current water on the central EAMS in the Middle Holocene24,25, while evidence based on diatom assemblage counts also suggest the arrival of more Kuroshio Current water in the TKS area after


the early Holocene26. Together, these paleocenographic evidences corroborate our modelling results about the initiation process of the 3T-S circulation system that transports more Kuroshio


Current water via the Taiwan Strait into the EAMS, as a result of sea level rise from −40 to −5 m. Moreover, the alkenone evidence for the weakening in the Tsugaru-Strait throughflow from 7


to 0 ka BP27 is also in line with our modelling results about the deceleration from an overshoot in the Tsugaru-Strait throughflow along sea level rise from −5 to 0 m (Fig. 2). Our results


provide an explaination to the mystery that the initial intrusion of the TKS throughflow into the Sea of Japan was continuously established since the early Holocene, despite the TKS being


open already under glacial sea level low-stand conditions28,29,30,31,32 (Fig. 2b). Here, we propose the opening of the Soya Strait to act as the necessary and critical control to ultimately


develop the TKS throughflow into the Sea of Japan, as a process in the establishment course of the 3T-S circulation system once sea level rise exceeds −40 m during the last deglaciation. We


thus provide an alternative hypothesis to the existing narrative that regional effects of irregular gateway shape (Fig. 2b) at the TKS affect the change in the TKS throughflow29,30. In


essence, our mechanism provides an unifying explanation for the coexistence of the lake-like conditions28,31 in the Sea of Japan with an open TKS under maximal glacials. Moreover, according


to paleclimate evidences, the aburpt weakening of the TKS throughflow when sea level rise exceeded −5 m at 7 ka BP is also synchronous with a weakening in Asian summer33 and strengthing in


winter monsoon34 (Fig. 2h). Within the atmosphere-ocean coupled system, the summer and winter change in the Asian monsoons commonly act to decelerate the TKS throughflow, by inducing


anomulous southward wind-driven effect over the EAMS. Similarly, although on centennial scale, a weakening in the TKS throughflow at 7 and 4 ka BP also coincides with the resembled change in


the Asian monsoon system (Fig. 2h). Here, our modeling results thus argue that the sea level rise exceeding −5 m acts as a control, extra to the contribution by Asian monsoons, in


triggering the weakening the TKS throughflow at 7 ka BP. Our modelling results have important implications for paleoceanographic studies, as proxies recording seasonal features may be biased


in reconstructing the EAMS circulation since the last deglaciation. According to our modelling experiments, seasonality in the throughflows via the Taiwan Strait, TKS, Tsugaru Strait and


Soya Strait is commonly developed synchronous with the establishment of their climatology mean states. Generally, it also presents continuous intensification coherent with the growth in the


climatology mean strength along with sea level rise (Fig. 2a–d and Supplementary fig. 6). Here, we attribute the stronger seasonality in the EAMS circulation to the growing Taiwan-Strait


throughflow that carries more Kuroshio Current waters of high seasonal variability35,36 into the EAMS. As a consequence, the larger seasonal offsets relative to the annual mean state may


result in higher uncertainties to interpolate marine proxy results in corporating climate seasonality signals. We note that our modelling simulations with different sea levels have been


carried out with identical atmospheric and ocean boundary forcings, thus in term of diagnose about stand-alone effect of sea levels on the EAMS circulation. As a result, the


glacial-interglacial change of Asian monsoons37,38 and tropical Pacific ocean circulation39 through time may induce further complexity to the seasonality in the EAMS circulation. Our


findings suggest that the existence of two types thresholds via ‘ocean-gateway effect’ and ‘around-island integral constraint’ in triggering rapid shift of the EAMS circulation due to sea


level rise since the last deglacition. In sequence, they may explain the nonlinear change in the EAMS circulation at −40 and −5 m sea level, respectively (Fig. 4). Developing from previous


estimations28,40,41 about a linkage between the EAMS circulation and sea level rise during the last deglaciation, our results suggested −40 and −5 m as the sea-level thresholds in stepwisely


shaping the modern EAMS circulation42. In particular, we develop the concept that the around-island integral constraint functions as a physically-based bridge that introduces a nonlinear


shift in open-ocean circulation to induce abrupt variations of throughflow in the marginal seas. This is alternative to classic assignments about the ‘ocean-gateway effect’14 and the shift


in atmospheric circulation due to the corresponding ice sheet variation along with sea level oscillation, in the relationship between sea levels and the global ocean circulation on


glacial-interglacial time scales. According to our findings, there are likely exitence of more abrupt change points in the relationship between sea level and EAMS circulation due to ocean


dynamics, besides well recognized ocean-gateway effect, when analyzing consequence of the ongoing sea level rise1,2. Moreover, this suggest potential occurrence of natural hazard induced by


abrupt change of the circulation in global marginal seas along the ongoing and future sea level rise. To fully understand the sensitivity of sea levels and the global marginal seas


circulation, it would be desirable to use a high-resolution Earth System Model in combination with the global warming climate forcings. METHODS We simulated the EAMS circulation based on sea


levels from −90 to 0 m of the present, using a high-resolution Regional Ocean Modeling System (ROMS) model43,44. The model has a horizontal resolution of 1/18° x 1/18° and 50 uneven


vertical layers, and ultilizes parameterization schemes as in Yu et al.45,46, the Mellor–Yamada level-2.5 scheme47 for vertical mixing and Smagorinsky scheme48 for horizontal diffusion. The


version of ROMS has been applied to simulate the modern North Pacific Ocean and EAMS, and the modelled circulation is comparable to instrumental oceanographic data45,46. In total, 11


experiments were conducted for the western North Pacific Ocean and the EAMS (Fig. 2a–d and Supplementary figs. 2, 3), with background sea levels incrementally increasing by 10 m from −90 m


to 0 m, as well as a subsequent experiment for −5 m sea level to better resolve more recent Holocene changes. In addition, the climatologically averaged monthly Coordinated Ocean-ice


Reference Experiments II (COREII) data49 were used as atmospheric forcing, while the climatologically averaged Simple Ocean Data Assimilation (SODA) data50 served as both initial and


boundary ocean conditions across all eleven experiments. Here, among experiments with varied sea levels, our application of the identical atmospheric and ocean lateral boundaries is to


highlight the diagnose about stand-alone impact of deglacial sea levels on the EAMS regional ocean circulation. By applying realistic surface and lateral boundary conditions, the conclusion


reached here may change due to the interactions between the air and sea, and the changes in ocean properties associated with the addition of ice sheet melt water into the ocean. Therefore,


to draw more affirmative conclusions, additional experiments using consistent surface and lateral boundary conditions are needed. Each run was integrated by 10 model years to allow for the


surface oceans to adjust to different sea levels. In the last five model years the simulated EAMS circulations were checked for the development of their quasi-equilibrium states regarding


the structure and intensities, respectively (see Supplementary fig. 4). DATA AVAILABILITY All relevant data in this paper will be uploaded to the PANGAEA Data Publisher. CODE AVAILABILITY


MPI-ESM climate model codes are available by a registration at https://www.myroms.org, and the scripts used to generate the figues are available from the corresponding author on request.


REFERENCES * Horton, B. P. et al. Estimating global mean sea-level rise and its uncertainties by 2100 and 2300 from an expert survey. _NPJ Clim. Atmos. Sci._ 3, 18 (2020). Article  Google


Scholar  * Garner, A. J. et al. Evolution of 21st century sea level rise projections. _Earth’s. Future_ 6, 1603–1615 (2018). Article  Google Scholar  * Church, J. A. et al. Sea Level Change.


In: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University


Press, Cambridge, United Kingdom and New York, NY, USA, 1137–1216 (2013). * Dutton, A. & Lambeck, K. Ice volume and sea level during the last interglacial. _Science_ 337, 216–219 (2012).


Article  CAS  Google Scholar  * Dyer, B. et al. Sea-level trends across The Bahamas constrain peak last interglacial ice melt. _Proc. Natl Acad. Sci._ 118, e2026839118 (2021). Article  CAS


  Google Scholar  * Oppo, D. W. & Sun, Y. Amplitude and timing of sea-surface temperature change in the northern South China Sea: Dynamic link to the East Asian monsoon. _Geology_ 33,


785–788 (2005). Article  CAS  Google Scholar  * Li, T. et al. Formation and evolution of the modern warm current system in the East China Sea and the Yellow Sea since the last deglaciation.


_Chin. J. Oceanol. Limnol._ 27, 237 (2009). Article  Google Scholar  * Liu, J. et al. Sea level changes of the Yellow Sea and formation of the Yellow Sea Warm Current since the last


deglaciation. _Mar. Geol. Quat. Geol._ 19, 13–24 (1999). Google Scholar  * Ichikawa, H. & Beardsley, R. C. Temporal and spatial variability of volume transport of the Kuroshio in the


East China Sea. _Deep Sea Res. Part I: Oceanographic Res. Pap._ 40, 583–605 (1993). Article  Google Scholar  * Vogt‐Vincent, N. S. & Mitarai, S. A persistent Kuroshio in the glacial East


China Sea and implications for coral paleobiogeography. _Paleoceanogr. Paleoclimatol._ 35, e2020PA003902 (2020). Article  Google Scholar  * Shen, X. et al. Reconstruction of Kuroshio


intrusion into the South China sea over the last 40 kyr. _Quat. Sci. Rev._ 290, 107622 (2022). Article  Google Scholar  * Fang, G., Zhao, B. & Zhu, Y. Water volume transport through the


Taiwan Strait and the continental skelf of the East China Sea measured with current meters. _Elsevier Oceanogr. Ser._ 54, 345–358 (1991). Article  Google Scholar  * Isobe, A. The


Taiwan-Tsushima Warm Current System: Its path and the transformation of the water mass in the East China Sea. _J. Oceanogr._ 55, 185–195 (1999). Article  Google Scholar  * Nathan, S. A.


& Leckie, R. M. Early history of the Western Pacific Warm Pool during the middle to late Miocene (~ 13.2–5.8 Ma): Role of sea-level change and implications for equatorial circulation.


_Palaeogeogr., Palaeoclimatol., Palaeoecol._ 274, 140–159 (2009). Article  Google Scholar  * Kawabe, M. Variations of current path, velocity, and volume transport of the Kuroshio in relation


with the large meander. _J. Phys. Oceanogr._ 25, 3103–3117 (1995). Article  Google Scholar  * Qiu, B. & Chen, S. Revisit of the occurrence of the Kuroshio large meander South of Japan.


_J. Phys. Oceanogr._ 51, 3679–3694 (2021). Article  Google Scholar  * Sawada, K. & Handa, N. Variability of the path of the Kuroshio ocean current over the past 25,000 years. _Nature_


392, 592–595 (1998). Article  CAS  Google Scholar  * Godfrey, J. S. A Sverdrup model of the depth-integrated flow for the world ocean allowing for island circulations. _Geophys.


Astrophysical Fluid Dyn._ 45, 89–112 (1989). Article  Google Scholar  * Yang, J. An oceanic current against the wind: How does Taiwan Island steer warm water into the East China Sea? _J.


Phys. Oceanogr._ 37, 2563–2569 (2007). Article  Google Scholar  * Qiu, B., Chen, S., Schneider, N., Oka, E. & Sugimoto, S. On the reset of the wind-forced decadal Kuroshio Extension


variability in late 2017. _J. Clim._ 33, 10813–10828 (2020). Article  Google Scholar  * Dong, Z. et al. Global sea level controlled the deep low-salinity pool evolution in the Japan Sea


since the last glacial period. _Quat. Sci. Rev._ 327, 108528 (2024). Article  Google Scholar  * Lambeck, K., Rouby, H., Purcell, A., Sun, Y. & Sambridge, M. Sea level and global ice


volumes from the Last Glacial Maximum to the Holocene. _Proc. Natl Acad. Sci._ 111, 15296–15303 (2014). Article  CAS  Google Scholar  * Zhao, B. et al. Sedimentary evolution of the Yangtze


River mouth (East China Sea) over the past 19,000 years, with emphasis on the Holocene variations in coastal currents. _Palaeogeogr., Palaeoclimatol., Palaeoecol._ 490, 431–449 (2018).


Article  Google Scholar  * Wang, Z. et al. Air-sea interactive forcing on phytoplankton productivity and community structure changes in the East China Sea during the Holocene. _Glob. Planet.


Change_ 179, 80–91 (2019). Article  Google Scholar  * Nan, Q. et al. Holocene paleoenvironment changes in the northern Yellow Sea: evidence from alkenone-derived sea surface temperature.


_Palaeogeogr., Palaeoclimatol., Palaeoecol._ 483, 83–93 (2017). Article  Google Scholar  * Shirota, K. et al. Changes in surface water masses in the northern East China Sea since the Last


Glacial Maximum based on diatom assemblages. _Prog. Earth Planet. Sci._ 8, 1–17 (2021). Article  Google Scholar  * Kawahata, H., Ishizaki, Y., Kuroyanagi, A., Suzuki, A. & Ohkushi, K. I.


Quantitative reconstruction of temperature at a Jōmon site in the Incipient Jōmon Period in northern Japan and its implications for the production of early pottery and stone arrowheads.


_Quat. Sci. Rev._ 157, 66–79 (2017). Article  Google Scholar  * Oba, T. Oceanic paleoenvironmental studies in Japan. _Quat. Res. (Daiyonki-Kenkyu)_ 30, 197–202 (1991). Article  Google


Scholar  * Domitsu, H. & Oda, M. Holocene influx of the Tsushima Current into the Japan Sea signalled by spatial and temporal changes in Neogloboquadrina incompta distribution.


_Holocene_ 18, 345–352 (2008). Article  Google Scholar  * Bae, S. W. et al. Sea surface temperature and salinity changes near the Soya Strait during the last 19 ka. _Quat. Int._ 344, 200–210


(2014). Article  Google Scholar  * Itaki, T., Ikehara, K., Motoyama, I. & Hasegawa, S. Abrupt ventilation changes in the Japan Sea over the last 30 ky: evidence from deep-dwelling


radiolarians. _Palaeogeogr., Palaeoclimatol., Palaeoecol._ 208, 263–278 (2004). Article  Google Scholar  * Dong, Z. et al. Paleoceanographic insights on meridional ventilation variations in


the Japan Sea since the Last Glacial Maximum: A radiolarian assemblage perspective. _Glob. Planet. Change_ 200, 103456 (2021). Article  Google Scholar  * Cheng, H. et al. The Asian monsoon


over the past 640,000 years and ice age terminations. _Nature_ 534, 640–646 (2016). Article  CAS  Google Scholar  * Zheng, X. et al. ITCZ and ENSO pacing on East Asian winter monsoon


variation during the Holocene: Sedimentological evidence from the Okinawa Trough. _J. Geophys. Res.: Oceans_ 119, 4410–4429 (2014). Article  Google Scholar  * Chuang, W. S. & Liang, W.


D. Seasonal variability of intrusion of the Kuroshio water across the continental shelf northeast of Taiwan. _J. Oceanogr._ 50, 531–542 (1994). Article  Google Scholar  * Qiu, B. &


Lukas, R. Seasonal and interannual variability of the North Equatorial Current, the Mindanao Current, and the Kuroshio along the Pacific western boundary. _J. Geophys. Res.: Oceans_ 101,


12315–12330 (1996). Article  Google Scholar  * Ha, K. J., Heo, K. Y., Lee, S. S., Yun, K. S. & Jhun, J. G. Variability in the East Asian monsoon: a review. _Meteorol. Appl._ 19, 200–215


(2012). Article  Google Scholar  * Wen, X., Liu, Z., Wang, S., Cheng, J. & Zhu, J. Correlation and anti-correlation of the East Asian summer and winter monsoons during the last 21,000


years. _Nat. Commun._ 7, 1–7 (2016). Article  Google Scholar  * Gibbons, F. T. et al. Deglacial δ18O and hydrologic variability in the tropical Pacific and Indian Oceans. _Earth Planet. Sci.


Lett._ 387, 240–251 (2014). Article  CAS  Google Scholar  * Tada, R., Irino, T. & Koizumi, I. Land‐ocean linkages over orbital and millennial timescales recorded in late Quaternary


sediments of the Japan Sea. _Paleoceanography_ 14, 236–247 (1999). Article  Google Scholar  * Oba, T. & Irino, T. Sea level at the last glacial maximum, constrained by oxygen isotopic


curves of planktonic foraminifera in the Japan Sea. _J. Quat. Sci._ 27, 941–947 (2012). Article  Google Scholar  * Gallagher, S. J. et al. The Pliocene to recent history of the Kuroshio and


Tsushima Currents: a multi-proxy approach. _Prog. Earth Planet. Sci.,_ 2, 17 (2015). Article  Google Scholar  * Shchepetkin, A. F. & McWilliams, J. C. The regional oceanic modeling


system (ROMS): a split-explicit, free-surface, topography-following-coordinate oceanic model. _Ocean Model._ 9, 347–404 (2005). Article  Google Scholar  * Shchepetkin, A. F. &


McWilliams, J. C. Correction and commentary for “Ocean forecasting in terrain-following coordinates: Formulation and skill assessment of the regional ocean modeling system” by. _J. Comput.


Phys._ 228, 8985–9000 (2009). Article  Google Scholar  * Yu, Y., Gao, H., Shi, J., Guo, X. & Liu, G. Diurnal forcing induces variations in seasonal temperature and its rectification


mechanism in the eastern shelf seas of China. _J. Geophys. Res.: Oceans_ 122, 9870–9888 (2017). Article  Google Scholar  * Yu, Y. et al. Importance of diurnal forcing on the summer salinity


variability in the East China sea. _J. Phys. Oceanogr._ 50, 633–653 (2020). Article  Google Scholar  * Mellor, G. L. & Yamada, T. Development of a turbulence closure model for


geophysical fluid problems. _Rev. Geophys._ 20, 851–875 (1982). Article  Google Scholar  * Smagorinsky, J. General circulation experiments with the primitive equations: I. The basic


experiment. _Monthly weather Rev._ 91, 99–164 (1963). Article  Google Scholar  * Griffies, S. M. et al. Coordinated ocean-ice reference experiments (COREs). _Ocean Model._ 26, 1–46 (2009).


Article  Google Scholar  * Carton, J. A., Chepurin, G. A. & Chen, L. SODA3: A new ocean climate reanalysis. _J. Clim._ 31, 6967–6983 (2018). Article  Google Scholar  Download references


ACKNOWLEDGEMENTS We are grateful to the colleagues in the Shandong Provincial Key Laboratory of Computer Networks and Key Laboratory of Marine Geology and Metallogeny, First Institute of


Oceanography, China. This study was funded by the National Natural Science Foundation of China (No. 42376032), the Ministry of Science and Technology of the People’s Republic of China (No.


2019YFE0125000), Jinan Science and Technology Bureau (No. 202228034), Taishan Scholar Program of Shandong (No. tspd20181216) and Key R&D Program of Shandong Province, China (No.


2022CXGC020106). AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Key Laboratory of Computing Power Network and Information Security, Ministry of Education, Shandong Computer Science Center,


Qilu University of Technology (Shandong Academy of Sciences), Jinan, China Xun Gong & Guangliang Liu * Laboratory for Marine Geology, Qingdao Marine Science and Technology Center,


Qingdao, China Xun Gong, Xuefa Shi & Zhi Dong * Institute for Advanced Marine Research, China University of Geosciences, Guangzhou, China Xun Gong, Xuesong Wang & Jiong Zheng *


Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Bremerhaven, Germany Xun Gong, Lester Lembke-Jene & Gerrit Lohmann * Shandong Provincial Key Laboratory of


Computing Power Internet and Service Computing, Shandong Fundamental Research Center for Computer Science, Jinan, China Xun Gong & Guangliang Liu * CAS Key Laboratory of Ocean


Circulation and Waves, Institute of Oceanology, and Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, China Yang Yu * Key Laboratory of Marine Sedimentology and


Environmental Geology, First Institute of Oceanography, Ministry of Natural Resources, Qingdao, China Xuefa Shi & Zhi Dong * Frontier Science Center for Deep Ocean Multispheres and Earth


System (FDOMES) and Physical Oceanography Laboratory, Ocean University of China, Qingdao, China Xiaopei Lin * Laoshan Laboratory, Qingdao, China Xiaopei Lin * University of Bremen, Bremen,


Germany Gerrit Lohmann Authors * Xun Gong View author publications You can also search for this author inPubMed Google Scholar * Yang Yu View author publications You can also search for this


author inPubMed Google Scholar * Xuefa Shi View author publications You can also search for this author inPubMed Google Scholar * Xiaopei Lin View author publications You can also search


for this author inPubMed Google Scholar * Guangliang Liu View author publications You can also search for this author inPubMed Google Scholar * Zhi Dong View author publications You can also


search for this author inPubMed Google Scholar * Xuesong Wang View author publications You can also search for this author inPubMed Google Scholar * Jiong Zheng View author publications You


can also search for this author inPubMed Google Scholar * Lester Lembke-Jene View author publications You can also search for this author inPubMed Google Scholar * Gerrit Lohmann View


author publications You can also search for this author inPubMed Google Scholar CONTRIBUTIONS X.G. designed this study, analysed the data, and initialize the manuscript. X.S. and X.L.


significantly improves the data interpolation. Y.Y. and G.L. jointly conducted the modelling experiments. X.G., Y.Y., X.S., G.L., X.L., Z.D., X.W., J.Z., L.L.J. and G.L. helped with the


improvement and revision of the manuscript. CORRESPONDING AUTHORS Correspondence to Xuefa Shi or Xiaopei Lin. ETHICS DECLARATIONS COMPETING INTERESTS The authors declare no competing


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ARTICLE CITE THIS ARTICLE Gong, X., Yu, Y., Shi, X. _et al._ Thresholds in East Asian marginal seas circulation due to deglacial sea level rise. _npj Clim Atmos Sci_ 8, 83 (2025).


https://doi.org/10.1038/s41612-025-00927-y Download citation * Received: 13 May 2024 * Accepted: 21 January 2025 * Published: 01 March 2025 * DOI: https://doi.org/10.1038/s41612-025-00927-y


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