A Methodology for Application of a Nowcast/Forecast System for Bottom Layer Dissolved Oxygen (DO) to Fisheries in Tokyo Bay

Abstract

Eutrophication is a serious problem in Tokyo Bay environment. As a result, hypoxic water mass occurs every year from spring to autumn. Since sea bass, caught in a trawl fishery in the bay, try to avoid hypoxic water mass, spatial distribution of DO in the bottom layer is the key information for the fishery. We thus developed a nowcast/forecast system for the bottom layer DO distribution coupling a coastal circulation model and an ecosystem model. We then enhanced the system with the assimilation of monitoring data, which is validated through the comparison between computation and measurements. Positions of sea bass catch and border of hypoxic water mass matched and the usefulness of the system have been confirmed.