WEB-BASED REALTIME MONITORING OF WATER QUALITY CONDITIONS IN THE KOREAN COASTAL WATERS

Young Jae Ro, Yang Ho Choi and Cha Kyum Kim

Chungnam National University, Yusung-ku, Kung-dong 220, Taejon, 305-764 Republic of Korea royoungj@cnu.ac.kr

This study is based on the operational realtime monitoring system for the water quality conditions in Korean coastal waters at two locations. To establish warning system for harmful algal bloom and other emergent episodes for local fishery farming, it is necessary to obtain very detailed information for abrupt change of water quality conditions. To make effective warning messages possible, required such information is required on a realtime basis. This study developed a realtime monitoring system of oceanic conditions (current, sea level, salinity, dissolved oxygen, turbidity) in the Chunsu Bay and the Namhae Bay, western and southern coastal waters of Korea, respectively. The system consist of three major subsystem of data loggers with sensor array in the sea water, to which wireless internet data terminal such as pda is connected and host computer on the remote location. The system produces the database of oceanic conditions with sampling interval of 10 minutes continuously. Realtime monitored data can be browsed on the Internet web pages in terms of text and graphics with query function for the existing database. The display pages contain the time series plot of temperature and other conditions, statistics of data-based parameters, recall of the past parameters, etc. In this study, we will describe seasonal and high frequency variation of temperature as well as other oceanic conditions in terms of descriptive statistical parameters and spectral analyses. Results of multivariate analyses will be given with emphasis of regressing time series of dissolved oxygen to various oceanic processes. In particular, episodes of oxygen depletion in summer season will be highlighted and is attempted to forecast with a stochastic model.