Detection of HAB Using Satellite Data and HABAS Program

摘要

In the Korean waters, the outbreaks of Harmful Algal Blooms(HABs) were sporadic until 1980s, but became frequent and widespread during the 1990s. They were generally observed from late spring to autumn, with peak in late summer season (from July to September). Since 1995, HABs (the dinoflagellate bloom of Cochlodinium polykrikoides) became more frequent and widespread in whole coastal area of the South sea and East sea, persisted nearly two months. Therefore, an early HAB warning system is very necessary to mitigate the economical loss of aquaculture industries. HAB monitoring wrer carried out by vessel cruising, patrolling coastal waterfront, aircraft observation and remote sensing. We had collected the dispersion area of HAB using vessel cruising and aircraft observation. A biological and chemical parameters of coastal water environment are monitored, including phytoplankton abundance, density, chlorophyll concentration, nutrients and physical parameters such as temperature, salinity, pH, water transparency and tidal currents. Meteorological data such as wind, precipitation, sun light intensity were analyzed for the dispersion of HABs. However, we need to more organized HAB information system for construction of HAB database system and to develop the detection algorithm using satellite data. In this study, I would like to introduce the HABAS(Harmful Algal Blooms Analysis System), which is developed by visual basic and Map object. HABAS program shows the dispersion area, species and density of daily algal bloom from 1995 to 2004 in Korean waters. Satellite data such as Landsat, SPOT, OCM, MODIS were used for detection of HAB and compared with in-situ data collected by vessel cruising. Long filamentary structures of algal blooms are detectable in the Landsat imagery, which means that the filaments are wider than 30 m. These satellite images of HAB were displayed with HABAS program.