Concentrations of some taxonomic of functional groups such as Coccolithophorides, Cyanobacteria etc.
The Indonesian archipelago is located in the tropics between the Pacific and Indian oceans and the Asian and Australian continents. This particular location in the Asian-Australian Monsoon system gives it a unique role in the regional and global climate system.
Two main oceanographic processes have been the focus of research in Indonesian waters. Upwelling, induced by southeasterly winds generating Ekman offshore transport of surface water along the coast of South Java; and the through flow phenomenon, where warm water from the western Pacific Ocean is transported to the Indian Ocean through the Makassar Strait, the Lombok Strait, the Ombai Strait and the Timor passage due to sea-level differences between these two regions.
Hendiarti et al (2004) proved that satellite imagery could be successfully applied to distinguish different water types in Sunda Strait area and used SeaWiFS data in combination with SST images to investigate monsoonal dependence and spatial extent of upwelling along the southeast Java coast, transport of Java Sea water into the Sunda Strait , and coastal discharge in the western Java Sea. For typical years, they concluded that upwelling and through flow phenomena occur during the southeast monsoon (June to September) with chlorophyll concentrations higher than 0.8 mg.m-3 and SST values lower than 28°C characterizing the upwelling events, and typical values for the through flow in the Sunda Strait of about 0.5 mg.m-3 and SST higher than 29.5°C. High concentrations of derived chlorophyll corresponded to high pelagic fish catches.
During the rainy season (December to March) large amount of discharged waters occur in the coastal regions of East Sumatra due to the high diffuse impacts of fish farms, aquaculture and mangrove coasts. High diffuse inflow, driven by westerly winds, was observed from chlorophyll images with concentrations of 3-10mg.m-3 (Hendiarti et al 2004). Strong river plume discharge were observed during transition phase from the rainy to dry season, during March and April, with high concentrations of suspended particulate matter (more than 8 mg.dm-3) and chlorophyll values higher than 2.5 mg.m-3.
Hendiarti N, Siegel H, Ohde T (2004) Investigation of different coastal processes in Indonesian waters using SeaWiFS data. Deep-Sea Research II, 51:85-97.
