Determining temporal and spatial variabilities of biological production in sulu sea using multi-remotely sensed data

Abstract

This study was conducted to investigate the temporal and spatial variation of the chlorophyll-a concentration over the past 13 years of Sea-viewing Wide Field-of-view Sensor (SeaWiFS) mission in the Sulu Sea area. The objectives of this study are to analyze the long term and spatial variability of the Chl-a concentration in Sulu Sea with special emphasize on the relationship between Chl-a concentration with the other oceanographic parameters such as sea surface temperature (SST), wind speed and wind directions. The Chl-a concentration were high during northeast monsoon which experience low SST. The fluctuation of Chl-a and SST are associated by the wind speed variation in this area. This suggests that during northeast monsoon, the increasing of wind speed intensifies water column mixing which entrains submerged cold- and nutrient-rich deep water to the surface layer, resulting in low SST and high nutrient in the surface layer. On the other hand, the southwest monsoon records dramatically decreasing of the Chl-a with regard to lower wind speed and surface water heating occurance. This promotes the downwelling process and weakens the upwelling one in the Sulu Sea [1] and as a result, this phenomenon influence reduction of nutrient upwelling to the surface layer, and thus produces lower Chl-a throughout the seasonal periods