Remote monitoring of oxygen levels in Savin Hill cove of Boston harbor

Seasonal oxygen levels of Savin Hill cove of Boston harbor were monitored using an interactive remote sensing device. A combination oxygen and temperature meter with RS232 linkage was used to process and send data to a portable computer. The sensing probes for the meter were suspended 1.5 meters from the water surface on a floating platform which rose and fell with the tide. Stored data were retrieved either on site by transfer computer or by telemetry using a modified cellular telephone connection to the remote sensor computer. There was a wide variation in seasonal oxygen values during the year. Spring and winter values showed lower temperatures with higher and more constant oxygen values than the summer and fall data. Summer and fall measurements showed a great deal of daily biotic input with oxygen levels ranging from 3 mg to 8 mg per liter of water. Fast fourier transforms of the data exhibited seasonal diel and tidal influences.