Applications of remotely-sensed ocean colour data in the Arabian Sea: A review

Abstract

Biological oceanography has been revolutionised by the provision of remotely sensed ocean colour data. These data provide us with a two-dimensional window into the synoptic state of the ecosystem by providing information on the surface biomass fields. This paper considers the advances made in the field of biogeochemical studies in the Arabian Sea through the exploitation of such remotely sensed ocean colour data. It concentrates on the advances made within the framework of the Joint Global Ocean Flux Study (JGOFS), focussing on the period 1994-1996 when the ARABESQUE (UK contribution to JGOFS) oceanographic campaigns took place. It considers the ocean-colour data and algorithms that were available during this period and how they have been used in biogeochemical studies of the area. It then considers advances in the post-JGOFS era and concludes with some recommendations for future studies in the Arabian Sea area. These include: the requirement for further development of regional algorithms for the retrieval of chlorophyll-a concentrations from ocean-colour data, due to the temporal and spatial variation of the bio-optical properties observed in the near- and surface waters, within and between the seasons; the further collection of shipboard measurements of P-I parameters, light absorption and pigment data throughout the year and further development of protocols for assigning these parameters to the Arabian Sea area, in the quest to improve primary production estimates on an ocean-basin scale.