• Anderson, S. P., , R. A. Weller, , and R. B. Lukas, 1996: Surface buoyancy forcing and the mixed layer of the western Pacific warm pool: Observations and 1D model results. J. Climate, 9 , 30563085.

    • Search Google Scholar
    • Export Citation
  • Bakun, A., 1996: Patterns in the ocean: Ocean processes and marine population dynamics. California Sea Grant College System Rep. T-037, La Jolla, California, 323 pp.

    • Search Google Scholar
    • Export Citation
  • Barber, R. T., , M. P. Sanderson, , S. T. Lindley, , F. Chai, , J. Newton, , C. C. Trees, , D. G. Foley, , and F. P. Chavez, 1996: Primary productivity and its regulation in the equatorial Pacific during and following the 1991–1992 El Niño. Deep-Sea Res, 43B , 933969.

    • Search Google Scholar
    • Export Citation
  • Behrenfeld, M. J., and Coauthors, 2001: Biospheric primary production during an ENSO transition. Science, 291 , 25942597.

  • Broad, K., 1999: Climate, culture and values: El Niño 1997–98 and Peruvian fisheries. Ph.D. dissertation,. Department of Anthropology, Columbia University, New York, NY, 311 pp.

    • Search Google Scholar
    • Export Citation
  • Cane, M. A., 1998: Climate change: A role for the tropical Pacific. Science, 282 , 5961.

  • Cane, M. A., , A. C. Clement, , A. Kaplan, , Y. Kushnir, , D. Pozdnyakov, , R. Seager, , S. E. Zebiak, , and R. Murtugudde, 1997: Twentieth-century sea surface temperature trends. Science, 275 , 957960.

    • Search Google Scholar
    • Export Citation
  • Chavez, F. P., , K. R. Buck, , S. K. Service, , J. Newton, , and R. T. Barber, 1996: Phytoplankton variability in the eastern and central tropical Pacific. Deep-Sea Res, 43B , 835870.

    • Search Google Scholar
    • Export Citation
  • Chavez, F. P., , P. G. Strutton, , G. E. Friederich, , R. A. Feely, , G. C. Feldman, , D. G. Foley, , and M. J. McPhaden, 1999: Biological and chemical response of the equatorial Pacific Ocean to the 1997–98 El Niño. Science, 286 , 21262131.

    • Search Google Scholar
    • Export Citation
  • Coale, K. H., and Coauthors, 1996: A massive phytoplankton bloom induced by an ecosystem-scale iron fertilization experiment in the equatorial Pacific Ocean. Nature, 383 , 495501.

    • Search Google Scholar
    • Export Citation
  • Cole, J. E., , R. B. Dunbar, , T. R. McClanahan, , and N. A. Muthiga, 2000: Tropical Pacific forcing of decadal SST variability in the western Indian Ocean over the past two centuries. Science, 287 , 617619.

    • Search Google Scholar
    • Export Citation
  • Cronin, M. F., , and W. S. Kessler, 2002: Seasonal and interannual modulation of mixed layer variability at 0°, 110°W. Deep-Sea Res, 49A , 117.

    • Search Google Scholar
    • Export Citation
  • da Silva, A. M., , C. C. Young, , and S. Levitus, 1994: Algorithms and Procedures. Vol. 1, Atlas of Surface Marine Data 1994. NOAA Atlas NESDIS 6, U.S. Department of Commerce, 83 pp.

    • Search Google Scholar
    • Export Citation
  • Frouin, R., , and B. Chertock, 1992: A technique for global monitoring of net solar irradiance at the ocean surface. Part I: Model. J. Appl. Meteor, 31 , 10561066.

    • Search Google Scholar
    • Export Citation
  • Godfrey, J. S., , R. A. Houze Jr., , R. H. Johnson, , R. Lukas, , J. L. Redelsperger, , A. Sumi, , and R. Weller, 1998: Coupled Ocean–Atmosphere Response Experiment (COARE): An interim report. J. Geophys. Res, 103 , 1439514450.

    • Search Google Scholar
    • Export Citation
  • Halpern, D., 1987: Observations of annual and El Niño thermal and flow variations at 0°, 110°W and 0°, 95°W during 1980–1985. J. Geophys. Res, 92 , 81978212.

    • Search Google Scholar
    • Export Citation
  • Hayes, S. P., , P. Chang, , and M. J. McPhaden, 1991: Variability of the sea surface temperature in the eastern equatorial Pacific during 1986–88. J. Geophys. Res, 96 , 1055310566.

    • Search Google Scholar
    • Export Citation
  • Hoerling, M. P., , J. W. Hurrell, , and T. Xu, 2001: Tropical origins for recent North Atlantic climate change. Science, 292 , 9092.

  • Kudela, R. M., , and F. P. Chavez, 1996: Bio-optical properties in relation to an algal bloom caused by iron enrichment in the equatorial Pacific. Geophys. Res. Lett, 23 , 37513754.

    • Search Google Scholar
    • Export Citation
  • Lehodey, P., , M. Bertignac, , J. Hampton, , A. Lewis, , and J. Picaut, 1997: El Niño Southern Oscillation and tuna in the western Pacific. Nature, 389 , 715718.

    • Search Google Scholar
    • Export Citation
  • Lewis, M. R., , M-E. Carr, , G. C. Feldman, , W. Esias, , and C. McClain, 1990: Influence of penetrating solar radiation on the heat budget of the equatorial Pacific Ocean. Nature, 347 , 543545.

    • Search Google Scholar
    • Export Citation
  • Linsley, B. K., , L. Ren, , R. B. Dunbar, , and S. S. Howe, 2000a: El Niño Southern Oscillation (ENSO) and decadal-scale climate variability at 10°N in the eastern Pacific from 1893 to 1994: A coral-based reconstruction from Clipperton Atoll. Paleoceanography, 15 , 322335.

    • Search Google Scholar
    • Export Citation
  • Linsley, B. K., , G. M. Wellington, , and D. P. Schrag, 2000b: Decadal sea surface temperature variability in the subtropical South Pacific from 1726 to 1997 A.D. Science, 290 , 11451148.

    • Search Google Scholar
    • Export Citation
  • McPhaden, M. J., 1999: Genesis and evolution of the 1997-98 El Niño. Science, 283 , 950954.

  • McPhaden, M. J., , and B. A. Taft, 1988: Dynamics of seasonal and intraseasonal variability in the eastern equatorial Pacific. J. Phys. Oceanogr, 18 , 5567.

    • Search Google Scholar
    • Export Citation
  • McPhaden, M. J., and Coauthors, 1998: The tropical ocean global atmosphere observing system: A decade of progress. J. Geophys. Res, 103 , 1416914240.

    • Search Google Scholar
    • Export Citation
  • Morel, A., , and D. Antoine, 1994: Heating rate within the upper ocean in relation to its bio-optical state. J. Phys. Oceanogr, 24 , 16521665.

    • Search Google Scholar
    • Export Citation
  • Morel, A., , and S. Maritorena, 2001: Bio-optical properties of oceanic waters: A reappraisal. J. Geophys. Res, 106 , 71637180.

  • Murtugudde, R., , J. Beauchamp, , and A. J. Busalacchi, 2002: Effects of penetrative radiation on the upper tropical ocean circulation. J. Climate, 15 , 470486.

    • Search Google Scholar
    • Export Citation
  • Nakamoto, S., , S. Prasanna Kumar, , J. M. Oberhuber, , J. Ishizaka, , K. Muneyama, , and R. Frouin, 2001: Response of the equatorial Pacific to chlorophyll pigment in a mixed layer isopycnal ocean general circulation model. Geophys. Res. Lett, 28 , 20212024.

    • Search Google Scholar
    • Export Citation
  • Ohlmann, J. C., , D. A. Siegel, , and L. Washburn, 1998: Radiant heating of the western equatorial Pacific during TOGA-COARE. J. Geophys. Res, 103 , 53795395.

    • Search Google Scholar
    • Export Citation
  • Ohlmann, J. C., , D. A. Siegel, , and C. D. Mobley, 2000: Ocean radiant heating. Part I: Optical influences. J. Phys. Oceanogr, 30 , 18331848.

    • Search Google Scholar
    • Export Citation
  • Payne, R. E., 1972: Albedo of the sea surface. J. Atmos. Sci, 29 , 959970.

  • Paytan, A., , M. Kastner, , and F. P. Chavez, 1996: Glacial to interglacial fluctuations in productivity in the equatorial Pacific as indicated by marine Barite. Science, 274 , 13551357.

    • Search Google Scholar
    • Export Citation
  • Picaut, J., , F. Masia, , and Y. du Penhoat, 1997: An advective-reflective conceptual model for the oscillatory nature of ENSO. Science, 277 , 663666.

    • Search Google Scholar
    • Export Citation
  • Rochford, P. A., , A. B. Kara, , A. J. Wallcraft, , and R. A. Arnone, 2001: Importance of solar subsurface heating in ocean general circulation models. J. Geophys. Res, 106 , 3092330938.

    • Search Google Scholar
    • Export Citation
  • Ryan, J. P., , P. S. Polito, , P. G. Strutton, , and F. P. Chavez, 2002: Unusual large-scale phytoplankton blooms in the equatorial Pacific. Progress in Oceanography, Vol. 55, Pergamon, 263–285.

    • Search Google Scholar
    • Export Citation
  • Sathyendranath, S., , A. D. Gouveia, , S. R. Shetye, , P. Ravindran, , and T. Platt, 1991: Biological control of surface temperature in the Arabian Sea. Nature, 349 , 5456.

    • Search Google Scholar
    • Export Citation
  • Siegel, D. A., , J. C. Ohlmann, , L. Washburn, , R. R. Bidigare, , C. T. Nosse, , E. Fields, , and Y. Zhou, 1995: Solar radiation, phytoplankton pigments and the radiant heating of the equatorial Pacific warm pool. J. Geophys. Res, 100 , 48854891.

    • Search Google Scholar
    • Export Citation
  • Siegel, D. A., , T. K. Westberry, , and J. C. Ohlmann, 1999: Cloud color and ocean radiant heating. J. Climate, 12 , 11011116.

  • Smith, R. C., , and K. S. Baker, 1978: The bio-optical state of ocean waters and remote sensing. Limnol. Oceanogr, 23 , 247259.

  • Strutton, P. G., , and F. P. Chavez, 2000: Primary productivity in the equatorial Pacific during the 1997–98 El Niño. J. Geophys. Res, 105 , 2608926101.

    • Search Google Scholar
    • Export Citation
  • Timmermann, A., , and E-F. Jin, 2003: Phytoplankton influences on tropical climate. Geophys. Res. Lett.,29, 2104, doi:10.1029/ 2002GL015434.

    • Search Google Scholar
    • Export Citation
  • Wang, T., 1993: Satellite-derived long term net solar radiation over the global ocean surface: Its relationship to low frequency SST variation and El Niño. M.A. thesis,. Department of Geography, University of California, Santa Barbara, 97 pp.

    • Search Google Scholar
    • Export Citation
  • Wang, W., , and M. J. McPhaden, 1999: The surface layer heat balance in the equatorial Pacific Ocean. Part I: Mean seasonal cycle. J. Phys. Oceanogr, 29 , 18121831.

    • Search Google Scholar
    • Export Citation
  • Wang, W., , and M. J. McPhaden, 2000: The surface layer heat balance in the equatorial Pacific Ocean. Part II: Interannual variability. J. Phys. Oceanogr, 30 , 28983008.

    • Search Google Scholar
    • Export Citation
  • Wang, W., , and M. J. McPhaden, 2001a: Surface layer temperature balance in the equatorial Pacific during the 1997/98 El Niño and 1998/99 La Niña. J. Climate, 14 , 33933407.

    • Search Google Scholar
    • Export Citation
  • Wang, W., , and M. J. McPhaden, 2001b: What is the mean seasonal cycle of surface heat flux in the equatorial Pacific? J. Geophys. Res, 106 , 837857.

    • Search Google Scholar
    • Export Citation
  • Wells, M. L., , G. K. Vallis, , and E. A. Silver, 1999: Tectonic processes in Papua New Guinea and past productivity in the eastern equatorial Pacific Ocean. Nature, 398 , 601604.

    • Search Google Scholar
    • Export Citation
  • White, W. B., , D. R. Cayan, , M. D. Dettinger, , and G. Auad, 2001: Sources of global warming in upper ocean temperature during El Niño. J. Geophys. Res, 106 , 43494367.

    • Search Google Scholar
    • Export Citation
  • Wolter, K., , and M. S. Timlin, 1998: Measuring the strength of ENSO—How does 1997/98 rank? Weather, 53 , 315324.

  • Zhang, R-H., , L. M. Rothstein, , and A. J. Busalacchi, 1998: Origin of the upper-ocean warming and El Niño change on decadal scales in the tropical Pacific Ocean. Nature, 391 , 879883.

    • Search Google Scholar
    • Export Citation
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Biological Heating in the Equatorial Pacific: Observed Variability and Potential for Real-Time Calculation

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  • 1 State University of New York at Stony Brook, Stony Brook, New York
  • | 2 Monterey Bay Aquarium Research Institute, Moss Landing, California
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Abstract

Changes in phytoplankton concentration, mixed layer depth, and incident radiation strongly modify the upper- ocean heat budget. An extreme example occurred during the 1997/98 El Niño–La Niña. In the central equatorial Pacific, biological heating of the mixed layer increased from ∼0.1°C month−1 in December 1997 (El Niño) to ∼1.0°C month−1 in July 1998 (La Niña). This change was due to 1) shoaling of the mixed layer from ∼100 to ∼20 m (∼56% of the 0.9°C month−1 increase); 2) a twentyfold increase in surface chlorophyll concentrations (∼29% of the increase), coincident with a shoaling of the subsurface chlorophyll maximum from ∼100 to ∼50 m; and 3) an increase in incident shortwave radiation from ∼175 to 275 W m−2 (∼15% of the increase). The observed range of heating rates (0.1°–1.0°C month−1) corresponds closely to the mean condition of the western (oligotrophic) and eastern (mesotrophic) equatorial Pacific, respectively. Increased phytoplankton concentrations act to retain heat near the surface and should result in shallower mixed layer depths. The influence of decadal changes in chlorophyll concentrations on heat storage was also quantified. The observed chlorophyll variability leads to interannual changes in penetrative heat flux (Ed,SW,PEN, the irradiance flux out of the bottom of the mixed layer) of the order of 5 W m−2, or from 65% to 170% of the mean. This variability is significant when compared with recent work that describes couplings between tropical and global ocean temperature dynamics. The analyses presented here show that satellite and buoy data can be used to accurately and simply estimate the biological contribution to heating for basin-scale studies, and possibly for future improvement of ocean circulation models.

Corresponding author address: Peter G. Strutton, Marine Sciences Research Center, State University of New York at Stony Brook, Stony Brook, NY 11794-5000. Email: peter.strutton@sunysb.edu

Abstract

Changes in phytoplankton concentration, mixed layer depth, and incident radiation strongly modify the upper- ocean heat budget. An extreme example occurred during the 1997/98 El Niño–La Niña. In the central equatorial Pacific, biological heating of the mixed layer increased from ∼0.1°C month−1 in December 1997 (El Niño) to ∼1.0°C month−1 in July 1998 (La Niña). This change was due to 1) shoaling of the mixed layer from ∼100 to ∼20 m (∼56% of the 0.9°C month−1 increase); 2) a twentyfold increase in surface chlorophyll concentrations (∼29% of the increase), coincident with a shoaling of the subsurface chlorophyll maximum from ∼100 to ∼50 m; and 3) an increase in incident shortwave radiation from ∼175 to 275 W m−2 (∼15% of the increase). The observed range of heating rates (0.1°–1.0°C month−1) corresponds closely to the mean condition of the western (oligotrophic) and eastern (mesotrophic) equatorial Pacific, respectively. Increased phytoplankton concentrations act to retain heat near the surface and should result in shallower mixed layer depths. The influence of decadal changes in chlorophyll concentrations on heat storage was also quantified. The observed chlorophyll variability leads to interannual changes in penetrative heat flux (Ed,SW,PEN, the irradiance flux out of the bottom of the mixed layer) of the order of 5 W m−2, or from 65% to 170% of the mean. This variability is significant when compared with recent work that describes couplings between tropical and global ocean temperature dynamics. The analyses presented here show that satellite and buoy data can be used to accurately and simply estimate the biological contribution to heating for basin-scale studies, and possibly for future improvement of ocean circulation models.

Corresponding author address: Peter G. Strutton, Marine Sciences Research Center, State University of New York at Stony Brook, Stony Brook, NY 11794-5000. Email: peter.strutton@sunysb.edu

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