Volume 55 (2008) Pages 1081-1085
Temporal and spatial variations of hypoxic water mass in Tokyo Bay were investigated based on intensive field surveys coupled with numerical simulation in Summer 2007. Measurements results showed that the hypoxic water mass existed in the bottom layer from the head to the mouth of the bay in the beginning of August. It was lifted up to the middle layer in the mid of August and disappeared in the beginning of following month. The analysis of observed seawater characteristics (temperature and salinity) and numerical simulation results suggested that these variations of hypoxic water mass were regulated by the combination between the upwelling phenomenon at the mouth of Tokyo bay and wind-driven current.