The studies have shown that SeaWiFS ocean colour sensor is a very useful data sources for estimating chlorophyll-a concentration. The research includes the identification of regression coefficient through modification of existing algorithm, which can be used to extract the chlorophyll-a concentration for Malaysia waters. The results show that the empirical model has significantly highest correlation to the in-situ data.
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The evolving capabilities of satellite sensors and data processing techniques provide a promising tool towards the development of fish forecasting and management techniques. The light absorbing pigment collectively known as chlorophyll-a is commonly used by oceanography as an index of phytoplankton concentration (Mansor et.al, 2001).
The remote sensing technology has been applied widely in the developed countries in relation to fish productivity (Mansor et.al, 2001). This technique has been applied in Malaysia in upgrading the industrial of fishery. Due to these, the integration between field sampling and remote sensing technique should be improved in order to improve the fishing productivity along the coastal area of Malaysia. The use of satellite remote sensing to provide synoptic measurements of the ocean is becoming increasingly important in fishing industry.
Several works on extensively chlorophyll-a can be found in Harding (1992) Mayo and Gitelson (1995), Hirawake (1996). However, these models were not for tropical region especially for Malaysian waters. Mansor et.al (2001) has highlighted the need of operational algorithm for estimation of chlorophyll-a concentration because currently there is no operational algorithm to extract chlorophyll-a for Malaysian waters.
In view of this problem this research focuses on measuring the concentration of chlorophyll-a in EEZ of East Coast Peninsular Malaysia from SeaWiFS data. In order to achieve this objective it is essential to determine an empirical relation between the chlorophyll-a and the radiances values recorded by the sensor. This study used SeaWiFS satellite data combined with in-situ data measurement of chlorophyll-a concentration in east coast of Peninsular Malaysia. Algorithm to estimate the chlorophyll-a concentration in the South China Sea generated by computation based on empirical method using radiance ratio of SeaWiFS channel.
Materials
Sea truth
The data from the sea truth campaigned of 24th August 2000 until 29th August 2000 were applied to obtain the correlation between chlorophyll-a concentration (mg/m3) and the radiance values in chosen channel of SeaWiFS image. The amount of concentration of chlorophyll-a was calculated based on blue, blue/green and green (442nm-555nm) reflectance ratios, this was done by selecting representative radiance values corresponding to in-situ data measurements.
