Detection of harmful algal blooms of Karenia mikimotoi using MODIS measurements: A case study of Seto-Inland Sea, Japan

Abstract The end of Sea-viewing Wide Field-of-view Sensor (SeaWiFS) mission makes harmful algal bloom (HAB) detection with moderate resolution satellite data now relies on Moderate Resolution Imaging Spectroradiometer (MODIS). Based on MODIS and in situ data collected in the coastal region of the western part of Seto-Inland Sea, Japan with HAB-forming algae Karenia mikimotoi , a simpler new satellite remote sensing-based HAB detection method was developed. The strength of this method is, although it does not require indigenous atmospheric correction scheme, it is expected to be able to classify K. mikimotoi blooms, diatom blooms, TSM-dominated waters, gelbstoff-dominated waters, and mixed waters in the optically complex coastal waters. We anticipate that our satellite remote sensing-based HAB detection method can operate as a valuable complementary tool assisting in situ HAB monitoring and as an integrated part of HAB early warning systems to mitigate HAB negative impacts not only in the coastal waters of the western part of Seto-Inland Sea, Japan, but also in the other coastal waters with different HAB-forming algae, providing that backscattering signature and pigment packaging of other HAB-forming algae are similar to those of K. mikimotoi .