MEPS 183:1-12 (1999)  -  doi:10.3354/meps183001

Modelling new production in the northwest Indian Ocean region

L. J. Watts1,*, S. Sathyendranath2,3, C. Caverhill2, H. Maass3, T. Platt2, N. J. P. Owens1

1Department of Marine Sciences and Coastal Management, Ridley Building, University of Newcastle Upon Tyne, Newcastle Upon Tyne NE1 7RU, United Kingdom
2Biological Oceanography Division, Bedford Institute of Oceanography, Dartmouth, Nova Scotia B2Y 4A2, Canada
3Oceanography Department, Dalhousie University, Halifax, Nova Scotia B3H 4J1, Canada

ABSTRACT: Oceanic new production is a potential avenue for the removal of atmospheric carbon dioxide to the deep abyss. The ability to estimate new production on large, ocean-basin scales has important implications for studies of the greenhouse effect. This paper describes the development of a method which will allow real-time estimates of new production on ocean-basin scales, given real-time data on ocean colour and sea-surface temperature from satellites. This study has concentrated on the northwest Indian Ocean region but the protocol developed could be geographically transportable. Results from a biogeochemical study carried out in the northwest Indian Ocean during a monsoon and an intermonsoon period in 1994 indicate that this region can be partitioned into 6 distinct provinces based on bathymetry, sea-surface temperature and chlorophyll measurements. Parameters that define the vertical structure in the biomass profile and the photosynthesis-light curve have been established for each province and these, in combination with archived satellite data, are used to compute the primary production for each province using an established light-dependent model. From our empirically derived relationship between the f-ratio and primary production, new production for the northwest Indian Ocean over these 2 different seasons is computed.

KEY WORDS: New production · f-ratio · Primary production · Biogeochemical provinces · Satellite remote sensing · Modelling · Northwest Indian Ocean

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