Distribution and interannual variation of winter phytoplankton blooms northwest of Luzon Islands from satellite observations

Authors

  • Hui Zhao State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
  • Dandan Sui State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
  • Qiang Xie State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
  • Guoqi Han Fisheries and Oceans Canada, Northwest Atlantic Fisheries Centre, St. John's, NL, Canada
  • Dongxiao Wang State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
  • Nancy Chen Fisheries and Oceans Canada, Northwest Atlantic Fisheries Centre, St. John's, NL, Canada
  • DanLing Tang State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China

Keywords:

Ekman pumping, entrainment, Northeastern South China Sea

Abstract

Phytoplankton blooms often occur in the offshore region northwest of Luzon Islands in winter. Using remote sensing data, including sea-surface temperature, monthly-mean mixed layer depth (MLD), wind speed (SP), and SeaWiFS-derived chlorophyll-a (Chl-a) data from September 1997 to February 2007, we investigate the spatial and interannual variation of the winter phytoplankton in the region along with in situ GTS (the Global Telecommunications System) XBT (Expendable Bathythermograph) data and climatological nitrate and temperature observations from World Ocean Atlas 2005. The results clearly show high winter phytoplankton biomass (i.e. Chl-a) and its interannual variation in the region. The lower Chl-a concentrations (∼0.2 mg m−3) appeared often in winters (e.g. 1997 and 1998) when there was weaker wind speed, Ekman pumping velocity (EPV) and entrainment velocity (EV), and shallower MLD; conversely higher Chl-a (>0.5 mg m−3) appeared in winters (e.g. 2001 and 2003) when there was higher subsurface temperature, stronger wind speed, EPV and EV, and deeper MLD. It is thought that wind-induced upwelling (Ekman pumping) and entrainment mixing may be important factors leading to the high winter Chl-a, and the wind speed and wind stress curl were good indicators of higher Chl-a; the positive correlation between subsurface temperature (and MLD) and Chl-a represented more warm water intrusion from the Northwest Pacific Ocean into the region in the higher Chl-a years.

References

Behrenfeld, M. J. and Falkowski, P. G. 1997. Photosynthetic rates derived from satellite-based chlorophyll concentration. Limnol. Oceanogr., 42(1): 1–20.

Behrenfeld, M. J., O’Malley, R. T., Siegel, D. A., McClain, C. R., Sarmiento, J. L., Feldman, G. C., Milligan, A. J., Falkowski, P. G., Letelier, R. M. and Boss, E. S. 2006. Climate-driven trends in contemporary ocean productivity. Nature, 444: 752–755.

Boyer, T. P., Antonov, J. I., Garcia, H. E., Johnson, D. R., Locarnini, R. A., Mishonov, A. V., Pitcher, M. T., Baranova, O. K. and Smolyar, I. V. 2006. NOAA Atlas NESDIS 60, Washington, D.C.: U.S. Government Printing Office.

Chao, S.-Y., Shaw, P.-T. and Wu, S.-Y. 1996. Deep water ventilation in the South China Sea. Deep-Sea Res. I, 43(4): 445–466.

Chen, C.-C., Shiah, F.-K., Chung, S.-W. and Liu, K.-K. 2006. Winter phytoplankton blooms in the shallow mixed layer of the South China Sea enhanced by upwelling. J. Mar. Syst., 59: 97–110.

Fang, G., Fang, W., Fang, Y. and Wang, K. 1998. A survey of studies on the South China Sea upper ocean circulation. Acta Oceanographica Taiwanica, 37(1): 1–16.

Farris, A. and Wimbush, M. 1996. Wind-induced Kuroshio intrusion into the South China Sea. J. Oceanogr., 52(6): 771–784.

Gong, G.-C., Liu, K.-K., Liu, C.-T. and Pai, S.-C. 1992. “The chemical hydrography of the South China Sea west of Luzon and a comparison with the west Philippine Sea”. In Terrestrial Atmospheric and Oceanic Sciences Vol. 3, 587–602.

Han, G. and Huang, W. 2009. Low-frequency sea level variability in the South China Sea and its relationship with ENSO. Theoretical and Applied Climatology, 97: 41–52.

Hu, J., Kawamura, H., Hong, H. and Qi, Y. 2000. A review on the currents in the South China Sea: Seasonal circulation, South China Sea warm current and a southwestward current and Kuroshio intrusion. J. Oceanogr., 56: 607–624.

Lalli, C. M. and Parsons, T. R. 1997. Biological Oceanography: An Introduction. 2nd Ed., Oxford: Pergamon Press.

Li, L., Nowlin, W. D. and Su, J. L. 1998. Anticyclonic rings from the Kuroshio in the South China Sea. Deep-Sea Res. I, 45(9): 1469–1482.

Liu, K.-K., Chao, S.-Y., Shaw, P. T., Gong, G.-C., Chen, C.-C. and Tang, T. Y. 2002. Monsoon-forced chlorophyll distribution and primary production in the South China Sea: observations and a numerical study. Deep Sea Res., Part I, 49: 1387–1412.

Liu, W. T. and Tang, W. 1996. “Equivalent neutral wind”. Vol. 96–17, JPL Publication. Available at http://airsea-www.jpl.nasa.gov/data/data.html

Martin, J. H., Knauer, G. A., Karl, Knauer, Broenkow, D M. and Karl, W. W. 1987. Vertex: carbon cycling in the northeast Pacific. Deep-Sea Res., 34: 267–286.

Mendoza, V. M., Villanueva, E. E. and Adem, J. 2005. On the annual cycle of the sea surface temperature and the mixed. Atmõsfera, 18(2): 127–148.

Morton, B. and Blackmore, G. 2001. South China Sea. Mar. Pollut. Bull., 42(12): 1236–1263.

Olivieri, E. T. 1983. Colonization, adaptations and temporal changes in diversity and biomass of a phytoplankton community in upwelled water off the Cape Peninsula, South Africa, in December 1979. S. Afr. J. Mar. Sci., l(1): 77–109.

Pan, Y, Tang, D. L. and Weng, D. H. 2010. Evaluation of the SeaWiFS and MODIS chlorophyll-a algorithms used for the North South China sea during the summer season. Terr. Atmos. Oceean. Sci., 20(6): 997–1005. doi: 10.3319/TAO.2010. 02.11.01(Oc)

Peñaflor, E. L., Villanoy, C. L., Liu, C. T. and David, L. T. 2007. Detection of monsoonal phytoplankton blooms in Luzon Strait with MODIS data. Remote Sensing of Environment doi:10.1016/j.rse.2007.01.019

Qu, T. 2000. Upper-layer circulation in the South China Sea. J. Phys. Oceanogr., 30: 1450–1460.

Shaw, P.-T. 1991. The seasonal variation of the intrusion of the Philippine Sea into the South China Sea. J. Geophys. Res., 96: 821–827.

Shaw, P.-T., Chao, S.-Y., Liu, K.-K., Pai, S.-C. and Liu, C.-T. 1996. Winter upwelling off Luzon in the northeastern South China Sea. J. Geophys Res., 101(C7): 16435–16488.

Sverdrup, H. U., Johnson, M. W. and Fleming, R. H. 1946. “The Oceans: Their physics, chemistry and general biology”. New York: Prentice Hall Inc..

Tang, D. L., Ni, I. H., Kester, D. R. and Müller-Karger, F. E. 1999. Remote sensing observations of winter phytoplankton blooms southwest of the Luzon Strait in the South China Sea. Mar. Ecol. Prog. Ser., 191: 43–51.

Udarbe-Walker, M. J.B. and Villanoy, C. L. 2001. Structure of potential upwelling areas in the Philippines. Deep-Sea Research I, 48: 1499–1518.

Wang, G. H., Su, J. L. and Chu, P. C. 2003. Mesoscale eddies in the South China Sea observed with altimeter data. Geophys. Res. Lett., 30(21) doi:10.1029/2003GL018532

Zhao, H. and Tang, D. L. 2007. Effect of 1998 El Niño on the distribution of phytoplankton in the South China Sea. J. Geophys. Res., 112: C02017 doi:10.1029/2006JC003536

Zheng, Z.-W., Ho, C.-R. and Kuo, N.-J. 2007. Mechanism of weakening of west Luzon eddy during La Niña years. Geophys. Res. Lett., 34: L11604 doi:10.1029/2007GL030058

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Published

2012-01-01

Issue

Vol. 15 No. 1 (2012): Marine Environmental Change of the South China Sea

Section

Research article

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