QARTOD Dissolved Oxygen group

1. QARTOD Dissolved Oxygen group

2. Prelude • Limited group with limited experience with DO probes • Much of the discussion focused on the YSI 6562 Rapid Pulse Dissolved Oxygen Probe

4. Question 1 – Identify existing and emerging standards that should be considered. (No standards just common practices) • Pre-deployment calibrations ***(Incorporated into data stream) • Post-deployment calibrations ***(Incorporated into data stream) • In-water, simultaneous readings with freshly calibrated reference sensors • Water sample collection for analysis (Winkler Titration) • Utilization of manufacturer recommendations for instruments • Historical comparisons • Proper storage of instruments between deployments

5. Question 2 – List the manufacturer specifications that should be used to evaluate the instrument. • Manufacturer’s specifications can be subjective • Accuracy was noted to be a general term • Significant differences between a piece of equipment’s specified accuracy, its calibrated accuracy achieved, and its ongoing accuracy during an extended operational deployment. • Sensor behavior is highly dependent on the type of sensor and the environment in which it is deployed.

6. Question 3 –Processes a user can employ to confirm that a sensor is producing the highest quality data. • Purchasing the correct instrument for the job • Maintaining the sensors in good working order • Pre- and post- calibrations • Manufacturer recommendations should always be followed to insure proper operation

7. Question 4 – Identify potential options or partnerships to conduct field verification of the system while deployed. • Ships of Opportunity, Research Programs, and Field Surveys are all considered good sources of verification data, assuming they are present and the data are available. • Climatology-- A good understanding of your operating environment • YSI allows the user to select “DO charge” as one of the parameters

8. Question 5 – Identify available venues where QA-related issues and information can be exchanged among users. • Manufacturer web sites • QARTOD - nautilus.baruch.sc.edu/twiki/bin/view • Marine Technology Society (MTS) - www.mtsociety.org/ • Marine Metadata Interoperability Project (MMI) - www.marinemetadata.org/ • EPA’s Environmental Technology Verification Program (ETV) - www.epa.gov/etv/ • EPA’s Environmental Monitoring and Assessment Program (EMAP) - www.epa.gov/docs/emap/ • National Estuarine Research Reserve System (NERRS) - nerrs.noaa.gov/ • USGS/EPA National Water Quality Monitoring Council Meeting (NWQCM) - acwi.gov/monitoring/ • Buoy Workshop (WHOI) - www.whoi.edu/buoyworkshop/2006/index.html • DMAC - dmac.ocean.us/index.jsp • ***Alliance for Coastal Technologies (ACT) - www.act-us.info***

9. Alliance for Coastal Technologies ***(ACT)*** • Singled out as a good venue for the exchange of information • Runs a database of available sensors that allows users to browse through and compare sensor specifications regardless of manufacturer. • Insight into real world performance • Sponsor Sensor workshops

10. Question 7 – Bio-fouling? • More closely related to QA rather then QC • Anti-fouling paints • Guards • Wipers • Gas generation • Frequent change over of sensors • QC Recommendations • Range check (difficult due to drift) • Develop algorithms to adjust sensor drift

11. Metadata Recommendations • Group was not necessarily fully equipped to complete discussion of metadata options • Extent of metadata reporting was noted to likely differ depending on the level of “real-time” being achieved • Requirements • Depends on sensor

12. DO Sample Discussion Questions • What are the specific QA/QC procedures that apply to: • Polarographic; pulsed and steady state, optical, and galvanic sensors • Moored vs. profiled, AUV, point measurements • Estuarine vs. ocean, scientific vs. management • High end, precise scientific instruments vs. low cost, not as precise monitoring instruments • Do different reporting units; %, mg/L, ml/L, M require different QC checks? • Is the data from different DO monitoring technologies intercomparable? If not, how should they be differentiated? Are the data from newer technologies, i.e. optical sensors, fully accepted in the community? • If one method of automatic QC is to utilize ranges, what should be used for hard ranges (data is bad) and for soft ranges (data is questionable)?

13. Are gradient tests, the difference between two contiguous samples, a good way to test DO values? What about testing for stuck values? • Should Winkler titrations be used to verify DO values? If so, what standards in sample collection, processing, and chemical titrating need to be implemented to accomplish this? • Is there a way to standardize the post correction of DO data? How would this be used to supplement real-time checks? • What training standards should be utilized to improve the skill levels of users which should ultimately improve QA? • What metadata requirements are needed for DO? – Time, position, etc • DO sensors require conductivity and temperature data to calculate saturation and concentration? What steps are needed to adequately QA/QC these additional sensors? • How do you deal with bio-fouling? • What roadblocks might prevent the implementation of improved QA/QC methods? • Will tests be area specific?

14. Recommendations for the Next DO Breakout Group • More experienced users from a variety of backgrounds • Consider questions general to DO and also by sensor type. • Address questions from previous two slides

15. Questions and/or Discussion?