CTD Oxygen Sensor Calibration Procedures

Abstract

Oxygen sensors currently afford one of the few oppor tunities to acquire accurate measurements of a biogeochemical parameter at the same vertical re solution as CTD data. Electrochemical cells have been used to measure dissolved oxygen concentration in a water solution, initially blood (Clark et al., 1953) but soon thereafter aquatic environments (Kanwisher, 1959) for many decades. More recently, optical sensors have been applied to aquatic uses (Klimant et al., 1995). Here we present outlines of procedures on acquisition, processing, and calibration of oxygen data collected from both electrochemical and optical oxygen sensors. We focus only on one model of electrochemical cell, specifically the SeaBird Electronics SBE-43. He re also we provide detailed material on recent experience with acquisition, processing, and calib ration of data from optical oxygen sensors, specifically the Aanderaa Data Instruments Optode 3830 and the JFE Alec Rinko Optode. For all sensor types, readers should bear in mind th at oceanic oxygen measurement and calibration techniques are subject to improvement. This outlin e should be viewed only as a supplement to the existing literature, manufacturer documentation, and manufacturer instructions.