Cite this paper:
WANG Jing, YUAN Dongliang, ZHAO Xia. Impacts of Indonesian Throughflow on seasonal circulation in the equatorial Indian Ocean[J]. HaiyangYuHuZhao, 2017, 35(6): 1261-1274

Impacts of Indonesian Throughflow on seasonal circulation in the equatorial Indian Ocean

WANG Jing1,2, YUAN Dongliang1,2, ZHAO Xia1,2
1 Key Laboratory of Ocean Circulation and Waves, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China;
2 Laboratory for Ocean and Climate Dynamics, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
Impacts of the Indonesian Throughflow (ITF) on seasonal circulation in the equatorial eastern Indian Ocean are investigated using the ocean-only model LICOM by opening and closing ITF passages. LICOM had daily forcing from NCEP reanalysis data during 2000-2011. It can reproduce vertical profiles of mean density and buoyancy frequency of World Ocean Atlas 2013 data. The model also simulates well annual oscillation in the central Indian Ocean and semiannual oscillation in the eastern Indian Ocean of sea level anomalies (SLA) using satellite altimeter data, as well as the semiannual oscillation of surface zonal equatorial currents of Ocean Surface Current Analyses Real Time current data in the equatorial Indian Ocean. The wave decomposition method is used to analyze the propagation and reflection of equatorial long waves based on LICOM output. Wave analysis suggests that ITF blockage mainly influences waves generated from the Indian Ocean but not the Pacific Ocean, and eastern boundary reflections play an important role in semiannual oscillations of SLA and zonal current differences in the equatorial Indian Ocean associated with ITF. Reconstructed ITF-caused SLA using wave decomposition coefficient differences between closed and open ITF-passage experiments suggest both Kelvin and Rossby waves from the first baroclinic mode have comparable contributions to the semiannual oscillations of SLA difference. However, reconstructed ITFcaused surface zonal currents at the equator suggest that the first meridional-mode Rossby wave has much greater contribution than the first baroclinic mode Kelvin wave. Both reconstructed sea level and zonal currents demonstrate that the first baroclinic mode has a greater contribution than other baroclinic modes.
Key words:    Indonesian Throughflow (ITF) blockage|seasonal circulation|wave decomposition|semiannual oscillation|Indian Ocean   
Received: 2016-08-01   Revised: 2016-09-03
PDF (1329 KB) Free
Print this page
Add to favorites
Email this article to others
Articles by WANG Jing
Articles by YUAN Dongliang
Articles by ZHAO Xia
Boyer T P, Antonov J I, Baranova O K, Coleman C, Garcia H E, Grodsky A, Johnson D R, Locarnini R A, Mishonov A V, O'Brien T D, Paver C R, Reagan J R, Seidov D, Smolyar I V, Zweng M M. 2013. World Ocean Database 2013. Sydney Levitus, Ed., Alexey Mishonov, Technical Ed., NOAA Atlas NESDIS 72. 209p.
Clarke A J, Liu X. 1993. Observations and dynamics of semiannual and annual sea levels near the Eastern Equatorial Indian ocean boundary. J. Phys. Oceanogr., 23(2):386-399.
Clarke A J. 1983. The reflection of equatorial waves from oceanic boundaries. J. Phys. Oceanogr., 13(7):1 193-1 207.
Durland T S, Qiu B. 2003. Transmission of subinertial Kelvin waves through a strait. J. Phys. Oceanogr., 33(7):1 337-1 350.
Feng X, Liu H L, Wang F C, Yu Y Q, Yuan D L. 2013.Indonesian Throughflow in an eddy-resolving ocean model. Chin. Sci. Bull., 58(35):4 504-4 514.
Gent P R, Oneill K, Cane M A. 1983. A Model of the Semiannual Oscillation in the Equatorial Indian-Ocean. J.Phys. Oceanogr., 13(12):2 148-2 160.
Godfrey J S. 1996. The effect of the Indonesian throughflow on ocean circulation and heat exchange with the atmosphere:a review. J. Geophys. Res., 101(C5):12 217-12 237.
Gordon A L, Fine R A. 1996. Pathways of water between the Pacific and Indian oceans in the Indonesian seas. Nature, 379(6561):146-149.
Gordon A L. 2005. Oceanography of the Indonesian Seas and their throughflow. Oceanography, 18(4):14-27.
Han W Q, McCreary J P, Anderson D L T, Mariano A J. 1999.Dynamics of the eastern surface jets in the equatorial Indian Ocean. J. Phys. Oceanogr., 29(9):2 191-2 209.
Jensen T G. 1993. Equatorial variability and resonance in a wind-driven Indian Ocean model. J. Geophys. Res., 98(C12):22 533-22 552.
Kuswardani R T D, Qiao F L. 2014. Influence of the Indonesian Throughflow on the upwelling off the east coast of the South Java. Chin. Sci. Bull., 59(33):4 516-4 523.
Lee T, Fukumori I, Menemenlis D, Xing Z F, Fu L L. 2002.Effects of the Indonesian Throughflow on the Pacific and Indian oceans. J. Phys. Oceanogr., 32(5):1 404-1 429.
Levitus S, Boyer T P, Conkright M E, O'Brien T, Antonov J, Stephens C, Stathoplos L, Johnson D, Gelfeld R. 1998.World Ocean Database 1998, Vol. 1:Introduction, NOAA Atlas NESDIS 18. NOAA, Silver Spring, MD. 346p.
Li W, Liu H H, Zhang X L. 2004. Indonesian Throughflow in an eddy-permitting oceanic GCM. Chin. Sci. Bull., 49(21):2 305-2 310.
Liu H L, Li W, Zhang X H. 2005. Climatology and variability of the Indonesian Throughflow in an eddy-permitting oceanic GCM. Adv. Atmos. Sci., 22(4):496-508,
Liu H L, Yu Y Q, Li W, Zhang X H. 2004. LASG/IAP Climate System Ocean Model (LICOM1.0):User's Manual.Science Press, Beijing, China. p.1-10. (in Chinese)
McCreary J P, Miyama T, Furue R, Jensen T, Kang H W, Bang B, Qu T D. 2007. Interactions between the Indonesian Throughflow and circulations in the Indian and Pacific Oceans. Prog. Oceanogr., 75(1):70-114.
Nagura M, McPhaden M J. 2010. Dynamics of zonal current variations associated with the Indian Ocean dipole. J.Geophys. Res., 115(C11):C11026.
Pandey V K, Bhatt V, Pandey A C, Das I M L. 2007. Impact of Indonesian throughflow blockage on the Southern Indian Ocean. Curr. Sci., 93(3):399-406.
Potemra J T. 2001. Contribution of equatorial Pacific winds to southern tropical Indian Ocean Rossby waves. J. Geophys.Res., 106(C2):2 407-2 422.
Reverdin G. 1987. The upper equatorial Indian Ocean. The climatological seasonal cycle. J. Phys. Oceanogr., 17(7):903-927.
Schott F A, McCreary J P Jr. 2001. The monsoon circulation of the Indian Ocean. Prog. Oceanogr., 51(1):1-123.
Wijffels S, Meyers G. 2004. An intersection of oceanic waveguides:variability in the Indonesian Throughflow region. J. Phys. Oceanogr., 34(5):1 232-1 253.
Wyrtki K. 1973. Equatorial Jet in Indian Ocean. Science, 181(4096):264-266.
Yuan D L, Han W Q. 2006. Roles of equatorial waves and western boundary reflection in the seasonal circulation of the equatorial Indian Ocean. J. Phys. Oceanogr., 36(5):930-944.
Yuan D L, Rienecker M M, Schopf P S. 2004. Long wave dynamics of the interannual variability in a numerical hindcast of the equatorial Pacific Ocean circulation during the 1990s. J. Geophys. Res., 109(C5):C05019.
Zhou L, Murtugudde R, Jochum M. 2008. Seasonal influence of Indonesian Throughflow in the southwestern Indian Ocean. J. Phys. Oceanogr., 38(7):1 529-1 541.