Harmful algal blooms (red tide): a review of causes, impacts and approaches to monitoring and prediction

Red tide, an impermanent natural phenomenon including harmful algal blooms, causes changing the color of the sea generally to red or almost brown, and has a serious impact on environment along the coast and aquatic ecosystem. Due to recent extensive steady harmful algal blooms events that cause adverse impacts on human healthsome, aquaculture and tourism industry, and the entire economy of the coastal region, the need of society for realizing these phenomena is much greater than the past. In the recent decades, consideration of algal blooms and determination of bloom-former species and fundamental researches about dynamics of blooms are increased worldwide. Development in technology has increased our abilities in monitoring oceans and has provided new opportunities for blooms identification as well as defining the biological, physical and chemical parameters that lead to algae beginning, expansion and disappearance. In spite of these rapidly developing observational capabilities, harmful algal blooms' proceedings will carry on to be undersampled for the foreseeable future, due to their spacious spaced and temporal coverage. Therefore, reliance on models to help interpreting observations is necessary. To watch red tides, there are different methods: field observation and using sampling data, satellite-based studies, laboratory studies, modeling. (This item includes complex numerical models, conceptual models, simple analytic formula, semi-empirical models and aggregated box models or zero-dimensional models.) This paper proposes different observation and prediction methods ever used worldwide.