Oxygen Sensors
Oxygen Measurements at Folger
Oxygen sensors at Folger Deep show seasonal trends. The optode at Folger Deep records maximum oxygen levels in the winter when downwelling of the oxygen-rich water occurs, and records minimum oxygen levels in the summer when upwelling of nutrient-rich but oxygen-depleted water occurs.
Aanderaa Optodes
The Aanderaa Oxygen Optodes measures oxygen concentrations by shining modulated blue light at a gas permeable foil containing platinum porphyrin. This blue light excites the foil, causing it to emit red light at various phases, depending on the amount of oxygen present. The phase shift indicates oxygen concentration. These instruments generate measurements of temperature, oxygen saturation (%) and oxygen concentration (μmol/l). They can operate at temperatures between 0-40C to depths of 6000m.
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