Articles | Volume 17, issue 22
https://doi.org/10.5194/bg-17-5745-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-17-5745-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
23 Nov 2020
Research article |
| 23 Nov 2020
| 23 Nov 2020
A numerical model study of the main factors contributing to hypoxia and its interannual and short-term variability in the East China Sea
Haiyan Zhang
Department of Oceanography, Dalhousie University, 1355 Oxford Street, Halifax B3H 4R2, Nova Scotia, Canada
School of Marine Science and Technology, Tianjin University, Tianjin, China
Department of Oceanography, Dalhousie University, 1355 Oxford Street, Halifax B3H 4R2, Nova Scotia, Canada
Arnaud Laurent
Department of Oceanography, Dalhousie University, 1355 Oxford Street, Halifax B3H 4R2, Nova Scotia, Canada
Changwei Bian
Physical Oceanography Laboratory/CIMST, Ocean University of China, 266100, Qingdao, China
Qingdao National Laboratory for Marine Science and Technology, 266100, Qingdao, China
Related authors
Arnaud Laurent, Haiyan Zhang, and Katja Fennel
Biogeosciences, 19, 5893–5910, https://doi.org/10.5194/bg-19-5893-2022, https://doi.org/10.5194/bg-19-5893-2022, 2022
Short summary
Short summary
The Changjiang is the main terrestrial source of nutrients to the East China Sea (ECS). Nutrient delivery to the ECS has been increasing since the 1960s, resulting in low oxygen (hypoxia) during phytoplankton decomposition in summer. River phosphorus (P) has increased less than nitrogen, and therefore, despite the large nutrient delivery, phytoplankton growth can be limited by the lack of P. Here, we investigate this link between P limitation, phytoplankton production/decomposition, and hypoxia.
Arnaud Laurent, Bin Wang, Dariia Atamanchuk, Subhadeep Rakshit, Kumiko Azetsu-Scott, Chris Algar, and Katja Fennel
EGUsphere, https://doi.org/10.5194/egusphere-2025-3361, https://doi.org/10.5194/egusphere-2025-3361, 2025
This preprint is open for discussion and under review for Biogeosciences (BG).
Short summary
Short summary
Surface ocean alkalinity enhancement, through the release of alkaline materials, is a technology that could increase the storage of anthropogenic carbon in the ocean. Halifax Harbour (Canada) is a current test site for operational alkalinity addition. Here, we present a model of Halifax Harbour that simulates alkalinity addition at various locations of the harbour and quantifies the resulting net CO2 uptake. The model can be relocated to study alkalinity addition in other coastal systems.
Lina Garcia-Suarez, Katja Fennel, Neha Mehendale, Tronje Peer Kemena, and David Peter Keller
EGUsphere, https://doi.org/10.22541/essoar.173758192.24328151/v2, https://doi.org/10.22541/essoar.173758192.24328151/v2, 2025
This preprint is open for discussion and under review for Ocean Science (OS).
Short summary
Short summary
This study shows that regional ocean warming can make the Gulf Stream appear to shift north, even when its path remains stable in a changing climate. Temperature-based proxies, like the Gulf Stream North Wall, overestimate changes in its position. Methods based on sea surface height provide a more accurate view. These results help improve how we track changes in ocean currents and avoid misinterpreting signs of climate-related shifts.
Gianpiero Cossarini, Andrew Moore, Stefano Ciavatta, and Katja Fennel
State Planet, 5-opsr, 12, https://doi.org/10.5194/sp-5-opsr-12-2025, https://doi.org/10.5194/sp-5-opsr-12-2025, 2025
Short summary
Short summary
Marine biogeochemistry refers to the cycling of chemical elements resulting from physical transport, chemical reaction, uptake, and processing by living organisms. Biogeochemical models can have a wide range of complexity, from a single nutrient to fully explicit representations of multiple nutrients, trophic levels, and functional groups. Uncertainty sources are the lack of knowledge about the parameterizations, the initial and boundary conditions, and the lack of observations.
Kyoko Ohashi, Arnaud Laurent, Christoph Renkl, Jinyu Sheng, Katja Fennel, and Eric Oliver
Geosci. Model Dev., 17, 8697–8733, https://doi.org/10.5194/gmd-17-8697-2024, https://doi.org/10.5194/gmd-17-8697-2024, 2024
Short summary
Short summary
We developed a modelling system of the northwest Atlantic Ocean that simulates the currents, temperature, salinity, and parts of the biochemical cycle of the ocean, as well as sea ice. The system combines advanced, open-source models and can be used to study, for example, the ocean capture of atmospheric carbon dioxide, which is a key process in the global climate. The system produces realistic results, and we use it to investigate the roles of tides and sea ice in the northwest Atlantic Ocean.
Krysten Rutherford, Katja Fennel, Lina Garcia Suarez, and Jasmin G. John
Biogeosciences, 21, 301–314, https://doi.org/10.5194/bg-21-301-2024, https://doi.org/10.5194/bg-21-301-2024, 2024
Short summary
Short summary
We downscaled two mid-century (~2075) ocean model projections to a high-resolution regional ocean model of the northwest North Atlantic (NA) shelf. In one projection, the NA shelf break current practically disappears; in the other it remains almost unchanged. This leads to a wide range of possible future shelf properties. More accurate projections of coastal circulation features would narrow the range of possible outcomes of biogeochemical projections for shelf regions.
Robert W. Izett, Katja Fennel, Adam C. Stoer, and David P. Nicholson
Biogeosciences, 21, 13–47, https://doi.org/10.5194/bg-21-13-2024, https://doi.org/10.5194/bg-21-13-2024, 2024
Short summary
Short summary
This paper provides an overview of the capacity to expand the global coverage of marine primary production estimates using autonomous ocean-going instruments, called Biogeochemical-Argo floats. We review existing approaches to quantifying primary production using floats, provide examples of the current implementation of the methods, and offer insights into how they can be better exploited. This paper is timely, given the ongoing expansion of the Biogeochemical-Argo array.
Li-Qing Jiang, Adam V. Subhas, Daniela Basso, Katja Fennel, and Jean-Pierre Gattuso
State Planet, 2-oae2023, 13, https://doi.org/10.5194/sp-2-oae2023-13-2023, https://doi.org/10.5194/sp-2-oae2023-13-2023, 2023
Short summary
Short summary
This paper provides comprehensive guidelines for ocean alkalinity enhancement (OAE) researchers on archiving their metadata and data. It includes data standards for various OAE studies and a universal metadata template. Controlled vocabularies for terms like alkalinization methods are included. These guidelines also apply to ocean acidification data.
Katja Fennel, Matthew C. Long, Christopher Algar, Brendan Carter, David Keller, Arnaud Laurent, Jann Paul Mattern, Ruth Musgrave, Andreas Oschlies, Josiane Ostiguy, Jaime B. Palter, and Daniel B. Whitt
State Planet, 2-oae2023, 9, https://doi.org/10.5194/sp-2-oae2023-9-2023, https://doi.org/10.5194/sp-2-oae2023-9-2023, 2023
Short summary
Short summary
This paper describes biogeochemical models and modelling techniques for applications related to ocean alkalinity enhancement (OAE) research. Many of the most pressing OAE-related research questions cannot be addressed by observation alone but will require a combination of skilful models and observations. We present illustrative examples with references to further information; describe limitations, caveats, and future research needs; and provide practical recommendations.
Stefania A. Ciliberti, Enrique Alvarez Fanjul, Jay Pearlman, Kirsten Wilmer-Becker, Pierre Bahurel, Fabrice Ardhuin, Alain Arnaud, Mike Bell, Segolene Berthou, Laurent Bertino, Arthur Capet, Eric Chassignet, Stefano Ciavatta, Mauro Cirano, Emanuela Clementi, Gianpiero Cossarini, Gianpaolo Coro, Stuart Corney, Fraser Davidson, Marie Drevillon, Yann Drillet, Renaud Dussurget, Ghada El Serafy, Katja Fennel, Marcos Garcia Sotillo, Patrick Heimbach, Fabrice Hernandez, Patrick Hogan, Ibrahim Hoteit, Sudheer Joseph, Simon Josey, Pierre-Yves Le Traon, Simone Libralato, Marco Mancini, Pascal Matte, Angelique Melet, Yasumasa Miyazawa, Andrew M. Moore, Antonio Novellino, Andrew Porter, Heather Regan, Laia Romero, Andreas Schiller, John Siddorn, Joanna Staneva, Cecile Thomas-Courcoux, Marina Tonani, Jose Maria Garcia-Valdecasas, Jennifer Veitch, Karina von Schuckmann, Liying Wan, John Wilkin, and Romane Zufic
State Planet, 1-osr7, 2, https://doi.org/10.5194/sp-1-osr7-2-2023, https://doi.org/10.5194/sp-1-osr7-2-2023, 2023
Benjamin Richaud, Katja Fennel, Eric C. J. Oliver, Michael D. DeGrandpre, Timothée Bourgeois, Xianmin Hu, and Youyu Lu
The Cryosphere, 17, 2665–2680, https://doi.org/10.5194/tc-17-2665-2023, https://doi.org/10.5194/tc-17-2665-2023, 2023
Short summary
Short summary
Sea ice is a dynamic carbon reservoir. Its seasonal growth and melt modify the carbonate chemistry in the upper ocean, with consequences for the Arctic Ocean carbon sink. Yet, the importance of this process is poorly quantified. Using two independent approaches, this study provides new methods to evaluate the error in air–sea carbon flux estimates due to the lack of biogeochemistry in ice in earth system models. Those errors range from 5 % to 30 %, depending on the model and climate projection.
Arnaud Laurent, Haiyan Zhang, and Katja Fennel
Biogeosciences, 19, 5893–5910, https://doi.org/10.5194/bg-19-5893-2022, https://doi.org/10.5194/bg-19-5893-2022, 2022
Short summary
Short summary
The Changjiang is the main terrestrial source of nutrients to the East China Sea (ECS). Nutrient delivery to the ECS has been increasing since the 1960s, resulting in low oxygen (hypoxia) during phytoplankton decomposition in summer. River phosphorus (P) has increased less than nitrogen, and therefore, despite the large nutrient delivery, phytoplankton growth can be limited by the lack of P. Here, we investigate this link between P limitation, phytoplankton production/decomposition, and hypoxia.
Krysten Rutherford, Katja Fennel, Dariia Atamanchuk, Douglas Wallace, and Helmuth Thomas
Biogeosciences, 18, 6271–6286, https://doi.org/10.5194/bg-18-6271-2021, https://doi.org/10.5194/bg-18-6271-2021, 2021
Short summary
Short summary
Using a regional model of the northwestern North Atlantic shelves in combination with a surface water time series and repeat transect observations, we investigate surface CO2 variability on the Scotian Shelf. The study highlights a strong seasonal cycle in shelf-wide pCO2 and spatial variability throughout the summer months driven by physical events. The simulated net flux of CO2 on the Scotian Shelf is out of the ocean, deviating from the global air–sea CO2 flux trend in continental shelves.
Bin Wang, Katja Fennel, and Liuqian Yu
Ocean Sci., 17, 1141–1156, https://doi.org/10.5194/os-17-1141-2021, https://doi.org/10.5194/os-17-1141-2021, 2021
Short summary
Short summary
We demonstrate that even sparse BGC-Argo profiles can substantially improve biogeochemical prediction via a priori model tuning. By assimilating satellite surface chlorophyll and physical observations, subsurface distributions of physical properties and nutrients were improved immediately. The improvement of subsurface chlorophyll was modest initially but was greatly enhanced after adjusting the parameterization for light attenuation through further a priori tuning.
Thomas S. Bianchi, Madhur Anand, Chris T. Bauch, Donald E. Canfield, Luc De Meester, Katja Fennel, Peter M. Groffman, Michael L. Pace, Mak Saito, and Myrna J. Simpson
Biogeosciences, 18, 3005–3013, https://doi.org/10.5194/bg-18-3005-2021, https://doi.org/10.5194/bg-18-3005-2021, 2021
Short summary
Short summary
Better development of interdisciplinary ties between biology, geology, and chemistry advances biogeochemistry through (1) better integration of contemporary (or rapid) evolutionary adaptation to predict changing biogeochemical cycles and (2) universal integration of data from long-term monitoring sites in terrestrial, aquatic, and human systems that span broad geographical regions for use in modeling.
Arnaud Laurent, Katja Fennel, and Angela Kuhn
Biogeosciences, 18, 1803–1822, https://doi.org/10.5194/bg-18-1803-2021, https://doi.org/10.5194/bg-18-1803-2021, 2021
Short summary
Short summary
CMIP5 and CMIP6 models, and a high-resolution regional model, were evaluated by comparing historical simulations with observations in the northwest North Atlantic, a climate-sensitive and biologically productive ocean margin region. Many of the CMIP models performed poorly for biological properties. There is no clear link between model resolution and skill in the global models, but there is an overall improvement in performance in CMIP6 from CMIP5. The regional model performed best.
Cited articles
Baird, D., Christian, R. R., Peterson, C. H., and Johnson, G. A.: Consequences of hypoxia on estuarine ecosystem function: Energy diversion from consumers to microbes, Ecol. Appl., 14, 805–822, https://doi.org/10.1890/02-5094, 2004.
Bian, C., Jiang, W., and Greatbatch, R. J.: An exploratory model study of sediment transport sources and deposits in the Bohai Sea, Yellow Sea, and East China Sea, J. Geophys. Res.-Ocean., 118, 5908–5923, https://doi.org/10.1002/2013JC009116, 2013a.
Bian, C., Jiang, W., Quan, Q., Wang, T., Greatbatch, R. J., and Li, W.: Distributions of suspended sediment concentration in the Yellow Sea and the East China Sea based on field surveys during the four seasons of 2011, J. Mar. Syst., 121/122, 24–35, https://doi.org/10.1016/j.jmarsys.2013.03.013, 2013b.
Bianchi, T. S., DiMarco, S. F., Cowan, J. H., Hetland, R. D., Chapman, P., Day, J. W., and Allison, M. A.: The science of hypoxia in the northern Gulf of Mexico: A review, Sci. Total Environ., 408, 1471–1484, https://doi.org/10.1016/j.scitotenv.2009.11.047, 2010.
Bishop, M. J., Powers, S. P., Porter, H. J., and Peterson, C. H.: Benthic biological effects of seasonal hypoxia in a eutrophic estuary predate rapid coastal development, Estuar. Coast. Shelf Sci., 70, 415–422, https://doi.org/10.1016/j.ecss.2006.06.031, 2006.
Capet, A., Beckers, J. M., and Gregoire, M.: Drivers, mechanisms and long-term variability of seasonal hypoxia on the Black Sea northwestern shelf – Is there any recovery after eutrophication? Biogeosciences, 10, 3943–3962, https://doi.org/10.5194/bg-10-3943-2013, 2013.
Carton, J. A. and Giese, B. S.: A Reanalysis of Ocean Climate Using Simple Ocean Data Assimilation (SODA), Mon. Weather Rev., 136, 2999–3017, https://doi.org/10.1175/2007MWR1978.1, 2008.
Chen, C. C., Gong, G. C., and Shiah, F. K.: Hypoxia in the East China Sea: One of the largest coastal low-oxygen areas in the world, Mar. Environ. Res., 64, 399–408, https://doi.org/10.1016/j.marenvres.2007.01.007, 2007.
Chen, J., Cui, T., Ishizaka, J., and Lin, C.: A neural network model for remote sensing of diffuse attenuation coefficient in global oceanic and coastal waters: Exemplifying the applicability of the model to the coastal regions in Eastern China Seas, Remote Sens. Environ., 148, 168–177, https://doi.org/10.1016/j.rse.2014.02.019, 2014.
Chen, X., Shen, Z., Li, Y., and Yang, Y.: Physical controls of hypoxia in waters adjacent to the Yangtze Estuary: A numerical modeling study, Mar. Pollut. Bull., 97, 349–364, https://doi.org/10.1016/j.marpolbul.2015.05.067, 2015a.
Chen, X., Shen, Z., Li, Y., and Yang, Y.: Tidal modulation of the hypoxia adjacent to the Yangtze Estuary in summer, Mar. Pollut. Bull., 100, 453–463, https://doi.org/10.1016/j.marpolbul.2015.08.005, 2015b.
Dee, D. P., Uppala, S. M., Simmons, A. J., Berrisford, P., Poli, P., Kobayashi, S., and Vitart, F.: The ERA-Interim reanalysis: Configuration and performance of the data assimilation system, Q. J. Roy. Meteorol. Soc., 137, 553–597, https://doi.org/10.1002/qj.828, 2011.
Diaz, R. J. and Rosenberg, R.: Spreading dead zones and consequences for marine ecosystems, Science, 321, 926–929, https://doi.org/10.1126/science.1156401, 2008.
Egbert, G. D. and Erofeeva, S. Y.: Efficient inverse modeling of barotropic ocean tides, J. Atmos. Ocean. Technol., 19, 183–204, https://doi.org/10.1175/1520-0426(2002)019<0183:EIMOBO>2.0.CO;2, 2002.
Feng, Y., Fennel, K., Jackson, G. A., DiMarco, S. F., and Hetland, R. D.: A model study of the response of hypoxia to upwelling favorable wind on the northern Gulf of Mexico shelf, J. Mar. Syst., 131, 63–73, 2014.
Fennel, K. and Laurent, A.: N and P as ultimate and proximate limiting nutrients in the northern Gulf of Mexico: implications for hypoxia reduction strategies, Biogeosciences, 15, 3121–3131, https://doi.org/10.5194/bg-15-3121-2018, 2018.
Fennel, K. and Testa, J. M.: Biogeochemical controls on coastal hypoxia, Ann. Rev. Mar. Sci., 11, 105–130, https://doi.org/10.1146/annurev-marine-010318-095138, 2019.
Fennel, K., Wilkin, J., Levin, J., Moisan, J., O'Reilly, J., and Haidvogel, D.: Nitrogen cycling in the Middle Atlantic Bight: Results from a three-dimensional model and implications for the North Atlantic nitrogen budget, Global Biogeochem. Cy., 20, 1–14, https://doi.org/10.1029/2005GB002456, 2006.
Fennel, K., Hetland, R., Feng, Y., and DiMarco, S.: A coupled physical-biological model of the Northern Gulf of Mexico shelf: Model description, validation and analysis of phytoplankton variability, Biogeosciences, 8, 1881–1899, https://doi.org/10.5194/bg-8-1881-2011, 2011.
Fennel, K., Hu, J., Laurent, A., Marta-Almeida, M., and Hetland, R.: Sensitivity of hypoxia predictions for the northern Gulf of Mexico to sediment oxygen consumption and model nesting, J. Geophys. Res.-Ocean., 118, 990–1002, https://doi.org/10.1002/jgrc.20077, 2013.
Garcia, H. E., Boyer, T. P., Locarnini, R. A., Antonov, J. I., Mishonov, A. V., Baranova, O. K., Zweng, M. M., Reagan, J. R., Johnson, D. R., and Levitus, S.: World Ocean Atlas 2013, Vol. 3, Dissolved oxygen, apparent oxygen utilization, and oxygen saturation, Tech. rep., National Oceanic and Atmospheric Administration (NOAA), Silver Spring, MD, https://doi.org/10.7289/V5XG9P2W, 2013a.
Garcia, H. E., Locarnini, R. A., Boyer, T. P., Antonov, J. I., Baranova, O. K., Zweng, M. M., Reagan, J. R., Johnson, D. R., Mishonov, A. V., and Levitus, S.: World Ocean Atlas 2013, Vol. 4, Dissolved inorganic nutrients (phosphate, nitrate, silicate), Tech. rep., National Oceanic and Atmospheric Administration (NOAA), Silver Spring, MD, https://doi.org/10.7289/V5J67DWD, 2013b.
Grosse, F., Fennel, K., Zhang, H., and Laurent, A.: Quantifying the contributions of riverine vs. oceanic nitrogen to hypoxia in the East China Sea, Biogeosciences, 17, 2701–2714, https://doi.org/10.5194/bg-17-2701-2020, 2020.
Guo, X., Miyazawa, Y., and Yamagata, T.: The Kuroshio Onshore Intrusion along the Shelf Break of the East China Sea: The Origin of the Tsushima Warm Current, J. Phys. Oceanogr., 36, 2205–2231, https://doi.org/10.1175/JPO2976.1, 2006.
Haidvogel, D. B., Arango, H., Budgell, W. P., Cornuelle, B. D., Curchitser, E., Di Lorenzo, E., and Wilkin, J.: Ocean forecasting in terrain-following coordinates: Formulation and skill assessment of the Regional Ocean Modeling System, J. Comput. Phys., 227, 3595–3624, https://doi.org/10.1016/j.jcp.2007.06.016, 2008.
Laurent, A. and Fennel, K.: Simulated reduction of hypoxia in the northern Gulf of Mexico due to phosphorus limitation, Elementa, 2, 000022, https://doi.org/10.12952/journal.elementa.000022, 2014.
Laurent, A. and Fennel, K.: Time-evolving, spatially explicit forecasts of the northern Gulf of Mexico hypoxic zone, Environ. Sci. Technol., 53, 14449–14458, https://doi.org/10.1021/acs.est.9b05790, 2019.
Laurent, A., Fennel, K., Hu, J., and Hetland, R.: Simulating the effects of phosphorus limitation in the Mississippi and Atchafalaya river plumes, Biogeosciences, 9, 4707–4723, https://doi.org/10.5194/bg-9-4707-2012, 2012.
Laurent, A., Fennel, K., Cai, W.-J., Huang, W.-J., Barbero, L., and Wanninkhof, R.: Eutrophication-Induced Acidification of Coastal Waters in the Northern Gulf of Mexico: Insights into Origin and Processes from a Coupled Physical-Biogeochemical, Model. Geophys. Res. Lett., 44, 946–956, https://doi.org/10.1002/2016GL071881, 2017.
Li, D., Zhang, J., Huang, D., Wu, Y., and Liang, J.: Oxygen depletion off the Changjiang (Yangtze River) Estuary, Sci. China Ser. D, 45, 1137, https://doi.org/10.1360/02yd9110, 2002.
Li, H. M., Tang, H. J., Shi, X. Y., Zhang, C. S., and Wang, X. L.: Increased nutrient loads from the Changjiang (Yangtze) River have led to increased Harmful Algal Blooms, Harmful Algae, 39, 92–101, https://doi.org/10.1016/j.hal.2014.07.002, 2014.
Li, M., Lee, Y. J., Testa, J. M., Li, Y., Ni, W., Kemp, W. M., and Di Toro, D. M.: What drives interannual variability of hypoxia in Chesapeake Bay: Climate forcing versus nutrient loading?, Geophys. Res. Lett., 43, 2127–2134, https://doi.org/10.1002/2015GL067334, 2016.
Li, X., Bianchi, T. S., Yang, Z., Osterman, L. E., Allison, M. A., DiMarco, S. F., and Yang, G.: Historical trends of hypoxia in Changjiang River estuary: Applications of chemical biomarkers and microfossils, J. Mar. Syst., 86, 57–68, https://doi.org/10.1016/j.jmarsys.2011.02.003, 2011.
Liu, K. K., Yan, W., Lee, H. J., Chao, S. Y., Gong, G. C., and Yeh, T. Y.: Impacts of increasing dissolved inorganic nitrogen discharged from Changjiang on primary production and seafloor oxygen demand in the East China Sea from 1970 to 2002, J. Mar. Syst., 141, 200–217, https://doi.org/10.1016/j.jmarsys.2014.07.022, 2015.
Liu, S. M., Zhang, J., Chen, H. T., Wu, Y., Xiong, H., and Zhang, Z. F.: Nutrients in the Changjiang and its tributaries, Biogeochemistry, 62, 1–18, 2003.
Liu, S. M., Hong, G.-H., Ye, X. W., Zhang, J., and Jiang, X. L.: Liu, S. M., Hong, G.-H., Zhang, J., Ye, X. W., and Jiang, X. L.: Nutrient budgets for large Chinese estuaries, Biogeosciences, 6, 2245–2263, https://doi.org/10.5194/bg-6-2245-2009, 2009.
Locarnini, R. A., Mishonov, A. V., Antonov, J. I., Boyer, T. P., Garcia, H. E., Baranova, O. K., and Seidov, D.: World Ocean Atlas 2013, Vol. 1, Temperature, edited by: Levitus, S., A. Mishonov, Technical Ed.; NOAA Atlas NESDIS, 73, 40, https://doi.org/10.1182/blood-2011-06-357442, 2013.
Ning, X., Lin, C., Su, J., Liu, C., Hao, Q., and Le, F.: Long-term changes of dissolved oxygen, hypoxia, and the responses of the ecosystems in the East China Sea from 1975 to 1995, J. Oceanogr., 67, 59–75, https://doi.org/10.1007/s10872-011-0006-7, 2011.
Peña, A., Katsev, S., Oguz, T., and Gilbert, D.: Modeling dissolved oxygen dynamics and hypoxia, Biogeosciences, 7, 933–957, https://doi.org/10.5194/bg-7-933-2010, 2010.
Qian, W., Dai, M., Xu, M., Kao, S., Ji, Du, C., Liu, J., and Wang, L.: Non-local drivers of the summer hypoxia in the East China Sea off the Changjiang Estuary. Estuarine, Coast. Shelf Sci., 198, 393–399, https://doi.org/10.1016/j.ecss.2016.08.032, 2015.
Quiñones-Rivera, Z. J., Wissel, B., Justic, D., and Fry, B.: Partitioning oxygen sources and sinks in a stratified, eutrophic coastal ecosystem using stable oxygen isotopes, Mar. Ecol. Prog. Ser., 342, 69–83, https://doi.org/10.3354/meps342069, 2007.
Rabalais, N. N., Diaz, R. J., Levin, L. A., Turner, R. E., Gilbert, D., and Zhang, J.: Dynamics and distribution of natural and human-caused hypoxia, Biogeosciences, 7, 585–619, https://doi.org/10.5194/bg-7-585-2010, 2010.
Scavia, D., Bertani, I., Obenour, D. R., Turner, R. E., Forrest, D. R., and Katin, A.: Ensemble modeling informs hypoxia management in the northern Gulf of Mexico, P. Natl. Acad. Sci. USA, 114, 8823–8828, 2017.
Scully, M. E.: Physical controls on hypoxia in Chesapeake Bay: A numerical modeling study, J. Geophys. Res.-Ocean., 118, 1239–1256, https://doi.org/10.1002/jgrc.20138, 2013.
Smolarkiewicz, P. K. and Margolin, L. G.: MPDATA: A finite-difference solver for geophysical flows, J. Comput. Phys., 140, 459–480, 1998.
Song, G., Liu, S., Zhu, Z., Zhai, W., Zhu, C., and Zhang, J.: Sediment oxygen consumption and benthic organic carbon mineralization on the continental shelves of the East China Sea and the Yellow Sea, Deep-Sea Res. Pt. II, 124, 53–63, https://doi.org/10.1016/j.dsr2.2015.04.012, 2016.
Tong, Y., Zhao, Y., Zhen, G., Chi, J., Liu, X., Lu, Y., and Zhang, W.: Nutrient Loads Flowing into Coastal Waters from the Main Rivers of China (2006–2012), Sci. Rep., 5, 16678, https://doi.org/10.1038/srep16678, 2015.
Umlauf, L. and Burchard, H.: A generic length-scale equation for geophysical, J. Mar. Res., 61, 235–265, https://doi.org/10.1357/002224003322005087, 2003.
Wang, B.: Hydromorphological mechanisms leading to hypoxia off the Changjiang estuary, Mar. Environ. Res., 67, 53–58, https://doi.org/10.1016/j.marenvres.2008.11.001, 2009.
Wang, H., Dai, M., Liu, J., Kao, S. J., Zhang, C., Cai, W. J., and Sun, Z.: Eutrophication-Driven Hypoxia in the East China Sea off the Changjiang Estuary, Environ. Sci. Technol., 50, 2255–2263, https://doi.org/10.1021/acs.est.5b06211, 2016.
Wang, J., Yan, W., Chen, N., Li, X., and Liu, L.: Modeled long-term changes of DIN:DIP ratio in the Changjiang River in relation to Chl-a and DO concentrations in adjacent estuary, Estuar. Coast. Shelf Sci., 166, 153–160, https://doi.org/10.1016/j.ecss.2014.11.028, 2015.
Wei, H., He, Y., Li, Q., Liu, Z., and Wang, H.: Summer hypoxia adjacent to the Changjiang Estuary, J. Mar. Syst., 67, 292–303, https://doi.org/10.1016/j.jmarsys.2006.04.014, 2007.
Wei, H., Luo, X., Zhao, Y., and Zhao, L.: Intraseasonal variation in the salinity of the Yellow and East China Seas in the summers of 2011, 2012, and 2013, Hydrobiologia, 754, 13–28, https://doi.org/10.1007/s10750-014-2133-9, 2015.
Wu, R. S. S.: Hypoxia: From molecular responses to ecosystem responses, Mar. Pollut. Bull., 45, 35–45, https://doi.org/10.1016/S0025-326X(02)00061-9, 2002.
Yu, L., Fennel, K., and Laurent, A.: A modeling study of physical controls on hypoxia generation in the northern Gulf of Mexico, J. Geophys. Res.-Ocean., 120, 5019–5039, https://doi.org/10.1002/2014JC010634, 2015a.
Yu, L., Fennel, K., Laurent, A., Murrell, M. C., and Lehrter, J. C.: Numerical analysis of the primary processes controlling oxygen dynamics on the Louisiana shelf, Biogeosciences, 12, 2063–2076, https://doi.org/10.5194/bg-12-2063-2015, 2015b.
Yuan, D., Zhu, J., Li, C., and Hu, D.: Cross-shelf circulation in the Yellow and East China Seas indicated by MODIS satellite observations, J. Mar. Syst., 70, 134–149, https://doi.org/10.1016/j.jmarsys.2007.04.002, 2008.
Zhang, H., Zhao, L., Sun, Y., Wang, J., and Wei, H.: Contribution of sediment oxygen demand to hypoxia development off the Changjiang Estuary, Estuar. Coast. Shelf Sci., 192, 149–157, https://doi.org/10.1016/j.ecss.2017.05.006, 2017.
Zhang, J.: Nutrient elements in large Chinese estuaries, Cont. Shelf Res., 16, 1023–1045, https://doi.org/10.1016/0278-4343(95)00055-0, 1996.
Zhao, L. and Guo, X.: Influence of cross-shelf water transport on nutrients and phytoplankton in the East China Sea: A model study, Ocean Sci., 7, 27–43, https://doi.org/10.5194/os-7-27-2011, 2011.
Zheng, J., Gao, S., Liu, G., Wang, H., and Zhu, X.: Modeling the impact of river discharge and wind on the hypoxia off Yangtze Estuary, Nat. Hazards Earth Syst. Sci., 16, 2559–2576, https://doi.org/10.5194/nhess-16-2559-2016, 2016.
Zhou, F., Chai, F., Huang, D., Xue, H., Chen, J., Xiu, P., and Wang, K.: Investigation of hypoxia off the Changjiang Estuary using a coupled model of ROMS-CoSiNE, Prog. Oceanogr., 159, 237–254, https://doi.org/10.1016/j.pocean.2017.10.008, 2017.
Zhu, J., Zhu, Z., Lin, J., Wu, H., and Zhang, J.: Distribution of hypoxia and pycnocline off the Changjiang Estuary, China, J. Mar. Syst., 154, 28–40, https://doi.org/10.1016/j.jmarsys.2015.05.002, 2016.
Zhu, Z.-Y., Zhang, J., Wu, Y., Zhang, Y.-Y., Lin, J., and Liu, S.-M.: Hypoxia off the Changjiang (Yangtze River) Estuary: Oxygen depletion and organic matter decomposition, Mar. Chem., 125, 108–116, https://doi.org/10.1016/j.marchem.2011.03.005, 2011.
Zweng, M. M., Reagan, J. R., Antonov, J. I., Locarnini, R. A., Mishonov, A. V., Boyer, T. P., Garcia, H. E., Baranova, O. K., Johnson, D. R., Seidov, D., Biddle, M. M., and Levitus, S.: World Ocean Atlas 2013. Volume 2: Salinity, Tech. rep., National Oceanic and Atmospheric Administration (NOAA), Silver Spring, MD, https://doi.org/10.7289/V5251G4D, 2013.
Short summary
In coastal seas, low oxygen, which is detrimental to coastal ecosystems, is increasingly caused by man-made nutrients from land. This is especially so near mouths of major rivers, including the Changjiang in the East China Sea. Here a simulation model is used to identify the main factors determining low-oxygen conditions in the region. High river discharge is identified as the prime cause, while wind and intrusions of open-ocean water modulate the severity and extent of low-oxygen conditions.
In coastal seas, low oxygen, which is detrimental to coastal ecosystems, is increasingly caused...
Altmetrics
Final-revised paper
Preprint