Abstract
We conducted hydrographic observations throughout the year to investigate seasonal variations of the hypoxic water mass distribution in the Upper Gulf of Thailand (UGoT). Hypoxic water masses were observed from June to November, with half of the UGoT occupied by hypoxic water in September. A hypoxic water mass appeared in the northeastern part of the UGoT in June and August, and moved westward over time. Low-salinity surface water moved from east to west as the rotational direction of surface circulation shifted with the reversal of monsoon winds. Westward movement of low-salinity water causes strong stratification in the northwestern part of the UGoT, leading to severe hypoxia. Numerical experiments showed high dissolved oxygen consumption rates around and offshore of river mouths, where hypoxic water is generated. This finding suggests that hypoxic water masses are transported to the south by physical processes. We examined how flooding affects hypoxic water mass formation. The volume of hypoxia in a flood year was approximately 2.5 times greater than in a normal year. In addition, hypoxia occurred in the dry season and extensive hypoxia was observed in the year after flooding. These results suggest that the hypoxic water mass persists for a long time after flooding.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Altieri AH, Gedan KB (2015) Climate change and dead zones. Glob Change Biol 21:1395–1406. https://doi.org/10.1111/gcb.12754
Blumberg AF, Mellor GL (1987) A description of a three dimensional coastal ocean circulation model. In: Heaps N (ed) Three-dimensional coastal ocean models, Coastal estuarine stud. 4. AGU, Washington, pp 1–16 (208 pp)
Breitburg D, Levin LA, Oschlies A, Gregoire M, Chavez FP, Conley DJ, Garcon V, Gilbert D, Gutierrez D, Isensee K, Jacinto GS, Limburg KE, Montes I, Naqvi SWA, Pitcher GC, Rabalais NN, Roman MR, Rose KA, Seibel BA, Telszewski M, Yasuhara M, Zhang J (2018) Declining oxygen in the global ocean and coastal waters. Science 359(6371):eaam7240
Buranapratheprat A, Yanagi T, Sawangwong P (2002) Seasonal variations in circulation and salinity distributions in the Upper Gulf of Thailand: Modeling approach. La Mer 40:147–155
Buranapratheprat A, Yanagi T, Sojisuporn P, Booncherm C (2006) Influence of local wind field on seasonal circulation in the Upper Gulf of Thailand. Coast Mar Sci 30(1):19–26
Buranapratheprat A, Yanagi T, Matsumura S (2008a) Seasonal variation in water column conditions in the upper Gulf of Thailand. Cont Shelf Res 28:2509–2522
Buranapratheprat A, Yanagi T, Niemann OK, Matsumura S, Sojisuporn P (2008b) Surface chlorophyll-a dynamics in the Upper Gulf of Thailand revealed by a coupled hydrodynamic-ecosystem model. J Oceanogr 64:639–656
Buranapratheprat A, Niemann KO, Matsumura S, Yanagi T (2009) MERIS imageries to investigate surface chlorophyll in the upper Gulf of Thailand. Coast Mar Sci 33(1):22–28
Capet A, Beckers J-M, Gregoire M (2013) 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
Carstensen J, Andersen JH, Gustafsson BG, Conley DJ (2014) Deoxygenation of the Baltic Sea during the last century. Proc Natl Acad Sci USA 111(15):5628–5633
Cheevaporn V, Menasveta P (2003) Water pollution and habitat degradation in the Gulf of Thailand. Mar Poll Bull 47:43–51
Chongprasith P, Srineth V (1998) Marine water quality and pollution of the Gulf of Thailand. In: DM Johnston (ed) SEAPOL Integrated Studies of the Gulf of Thailand, vol 1. Southeast Asian Programe in Oecan Law, Policy and Management. pp 137–204
Diaz RJ (2001) Overview of hypoxia around the world. J Environ Qual 30:275–281
Diaz RJ, Rosenberg R (2008) Spreading dead zones and consequences for marine ecosystem. Science 321:926–929
Gale EL, Saunders MA (2013) The 2011 Thailand flood: climate causes and return periods. Weather 68(9):233–237
Hayami Y, Morimoto A, Sudaryanto A, Sachoemar IS, Soeyanto E, Rusdiansyah A, Saleh M (2020) A quasi-persistent hypoxic water mass in an equatorial coastal sea, Jakarta Bay, Indonesia. Est Coast Shelf Sci. 246:107030
Jacinto GS, Sotto LPA, Senal MIS, San Diego-McGlone ML, Escobar MTL, Amano A, Miller TW (2011) Hypoxia in Manila Bay, Philippines during the northeast monsoon. Mar Poll Bull 63:243–248
Kemp WM, Testa JM, Conley DJ, Gilbert D, Hagy JD (2009) Temporal responses of costal hypoxia to nutrient loading and physical controls. Biogeosciences 6:2985–3008
Kim H, Takayama K, Hirose N, Onitsuka G, Yoshida T, Yanagi T (2019) Biological modulation in the seasonal variation of dissolved oxygen concentration in the upper Japan Sea. J Oceanogr 75:257–271
Li M, Lee YJ, Testa JM, Li Y, Ni W, Kemp WM, Toro DMD (2016) What drives interannual variability of hypoxia in Chesapeake Bay: climate forcing versus nutrient loading? J Res Lett 43:2127–2134. https://doi.org/10.1002/2015GL067334
Lirdwitayaprasit T, Meksumpun S, Rungsupa S, Furuya K (2006) Seasonal variations in cell abundance of Noctiluca scintillans in the coastal waters off Chonburi Province, the Upper Gulf of Thailand. Coast Mar Sci 30(1):80–84
Mellor GL (2003) User guide for a three-dimensional, primitive equation, numerical ocean model (2003 version) (report, 53 pp). Program in Atmosphere and Ocean Science. Princeton Univ., Princeton
Mellor GL, Yamada T (1982) Development of a turbulence closure model for geophysical fluid problems. Rev Geophys 20:851–875
Morimoto A, Buranapratheprat A, Kaneda A, Sunitsakul S, Jintasaeranee P, Gunboa V, Tomita H (2013) Behavior of anoxic water in the Bangpakong estuary. Mar Res Indones 37(2):109–121
Nakajima M, Fujiwara T (2007) Estuarine circulation and hypoxic water mass in Osaka Bay. Bull Coast Ocenogr 44(2):157–163 (in Japanese with English abstract)
Onitsuka G, Yanagi T, Yoon J-H (2007) A numerical study on nutrient sources in the surface layer of the Japan Sea using a coupled physical-ecosystem model. J Geophys Res 112:C05042. https://doi.org/10.1029/2006JC003981
Rabalais NN, Turner RE (2019) Gulf of Mexico Hypoxia: past, present, and future. Limno Oceanogr Bull. https://doi.org/10.1002/lob.10351
Sotto LPA, Jacinto GS, Villanoy CL (2014) Spatiotemporal variability of hypoxia and eutrophication in Manila Bay, Philippines during the northeast and southwest monsoons. Mar Poll Bull 85:446–454
Smagorinsky JS (1963) General circulation experiments with the primitive equations. I. The basic experiment. Mon Weather Rev 91:99–164
Tong-U-Dom S, Na-U-Dom T, Buranapratheprat A (2017) The responses of a hydrodynamic model to different open boundary conditions in the Northern Gulf of Thailand. Burapha Sci J 22(3):259–272 (in Thai with English abstract)
Yanagi T, Yamada M (2014) Disappearance of hypoxia in Dokai Bay. Japan Bull Coast Ocenogr 51(2):203–208
Yu X, Guo X, Morimoto A, Buranapratheprat A (2018) Simulation of river plume behaviors in a tropical region: case study of the Upper Gulf of Thailand. Cont Shelf Res 153:16–29
Acknowledgements
We appreciate captain and crews of research vessel of Kasetsart University and students in Department of Aquatic Science, Faculty of Science, Burapha University for their help during hydrographic observations. This research was financially supported by the Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B) (26302001) and is partially supported by JSPS Core-to-core CREPSUM JPJSCCB20200009.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Morimoto, A., Mino, Y., Buranapratheprat, A. et al. Hypoxia in the Upper Gulf of Thailand: Hydrographic observations and modeling. J Oceanogr 77, 859–877 (2021). https://doi.org/10.1007/s10872-021-00616-3
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10872-021-00616-3