Handbook of best practices

4.2 Emergency procedures
Sometimes, emergency procedures need to be performed during the observatory
deployment. For example, unexpected early buoy recoveries have to be done. After the
recovery, it is essential to examine the system components and to modify items where
weaknesses had been exposed. For example, the data hub housing leaked for two
deployments, CTD cables connecting into the buoy had both failed in the two previous
deployments, etc.…
These operations are manpower consuming but they are necessary if we want to maintain
long term observatory with limited data gaps.
5. Quality control procedures and data correction (CNRS,
GEOMAR)
The primary objective of any ocean observing infrastructure is the acquisition of sensor data
which in turn is used to provide information about relevant ocean variables (e.g. salinity,
alkalinity, particulate organic matter, Chlorophyll-a concentration) for ocean system
understanding as well as for monitoring. The data that is delivered by a sensor requires
certain procedures for its conversion into an ocean variable. The procedures must consider
two basic expectations:
1. Quality control according to defined standards (or alternatively proper documentation
of new standards)
2. Quantification of data quality (e.g. standard error, error distribution)
Only if both expectations are addressed the derived variables can be used to quantify,
describe and assess the oceanic environment. Moreover, any use of data within a network
approach, that is merging information from one infrastructure with observations of other
networks, requires the two data quality procedures to be applied. For example, a chlorophylla
observation from a glider that surveys the waters around a FixO3 mooring can only be
merged with the single depth mooring data if the parameter “Chlorophyll-a” derived from
sensor data at the mooring is similar to the “Chlorophyll-a” derived from a maybe very
different sensor data that comes from the glider. In order to protocol the quality control we
follow the OceanSITES recommendations outlined in the “OceanSITES User’s Manual”
available from their website (www.oceansites.org).
Similar processes of quality control are used by other disciplines of ocean science active in
FixO3. The principles presented in this chapter are similar and under implementation by
projects such as EMODNET and SeaDataNet. EMSO is supporting these processes.
5.1. Quality control
5.1.1 Quality flag
For quality control flagging the concept as being worked out by the Data management team
of the international OceanSITES initiative is applied (table below).
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