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QA/QC Dissolved Oxygen

Sensor Information:

We currently deploy four types of sensors which measure Dissolved Oxygen. These are summarized in the following table:

Click sensor name for link to manufacturer website
SeaBird SBE 43
SeaBird SBE 37-SMP-IDO SeaBird SBE 63 Aandera Optode (3835)

Deployments (historical deployments marked with asterisk

Saturn01
Saturn02 (1m, 35m*)
Saturn03
Saturn04

Saturn051

Saturn02 (35m)

Saturn07

Glider
Sensor Methodology Polarographic/Clark electrode type sensor Polarographic/Clark electrode type sensor Optical/Luminescent Optical/Luminescent
Accuracy +/-2% (Initial) +/-2% (Initial) +/-2% (Initial)  <8uM below 160uM & 5% above 160uM

1 As part of a LOBO mooring

Calibration Evaluation:
The dissolved oxygen sensors are calibrated by the manufacturer. Sensors are recovered from the stations (where possible) on a quarterly basis for calibration checks. The sensors are placed in a well stirred and aerated tank and the readings are checked against each other and typically against one or more freshly calibrated sensors.  For remote buoy deployments the sensors are checked prior to and following recovery. The results of these sensor cross-checks are used to determine when a sensor should be returned to the manufacturer for re-calibration.  When a sensor's calibration is within 5% of a newly calibrated sensor, the sensor is typically redeployed. When the cross-check indicates that the calibration is off by more than 5%, the sensor is typically returned to the manufacturer but may be re-deployed in certain cases. In all instances the cross-check data are used to evaluate the sensor calibration and the data quality is flagged accordingly.  If a sensor is found to have a consistent offset based on subsequent cross-checks a correction to the data may be applied.  Data that have been adjusted will always have a flag of less than 'good' and the details of data adjustments will be provided in the metadata and can be found on the QA/QC Archive link at the bottom of this page.

 

Dissolved Oxygen QA/QC Archive

PDF or hyperlink Dates Description
SATURN-01    
data quality summary 8/3/10 - 1/31/17 evaluation/validation of calibration & sensor performance
s1-do01   Identifying and correcting for periods of insufficent flow to the sensor
SATURN-02    

data quality summary

2011 -2016 evaluation/validation of calibration & sensor performance
s2-do01   estimated salinity for 1m sensor deployment (2012)
SATURN-03    
data quality summary 6/13/10 - 5/1/19 evaluation/validation of calibration & sensor performance
  s3-do01 6/13/10 - 3/2/11 performance evalution; offset correction
s3_do02 12/18/12 - 5/31/13 performance evalution; offset correction
s3-do03 5/31/13 - 2/20/14 performance evalution; offset correction
s3-do04 2/20/14 - 11/8/14 performance evalution; offset correction
s3-do05 11/8/14 - 4/3/15 performance evalution; offset correction
s3-do06 4/4/15 - 10/30/15 performance evalution; offset correction
s3-do08 10/30/15 - 9/1/17 performance evalution; offset correction
SATURN-04    
data quality summary 9/23/09 - 2/1/17 evaluation/validation of calibration & sensor performance
s4-do01 4/8/13 - 2/20/14 performance evalution; offset correction
s4-do02 2/20/14 - 11/8/14 performance evalution; offset correction
s4-do03 11/8/14-2/23/16 performance evalution; offset correction
s4-do04 2/23/16 - 9/1/16 performance evalution; offset correction
SATURN-07    
data quality summary   evaluation/validation of calibration & sensor performance
s7-do01 1/15/15 - 2/1/17 performance evalution; offset correction
SATURN-09    
data quality summary 9/8/14 - 6/1/16 evaluation/validation of calibration & sensor performance
s9-do01 10/10/14 - 6/10/16 evaluation/validation of calibration
SATURN-10   evaluation/validation of calibration & sensor performance
data quality summary 8/28/16 - 12/17/16