MTP II - MATER
Mediterranean
Targeted
Project
II,
MAss Transfer
and Ecosystem
Response
A project of the European
Commission's
MArine Sciences & Technology (MAST)
programme
Eastern Basin(Aegean/Levantine Sea, S.E.
Ionian Basin)
Quality Checks
1. Objectives and General Description
2. Flag Scale
3. Check of the format, QC-0
4. Check of the Headers: date and location, QC-1
5. Check of the parameters, QC-2
6. Regional Parametrisation
Objectives
It is important to archive data set of good quality, directly usable for scientific or operational purposes. Therefore a cruise is only archived at the end of a series of quality checks, which is in conformity with the Intergovernmental Commission and MAST recommendations. Theese checks are a necessity for the historical data, but are also useful for recent data already validated by the scientific laboratories because any data handling is a potential source of error.
Each data set (cruise) is submitted globally to a series of automatic (objective) tests, followed by manual tests by displaying the results of the automatic test on a screen. As a result, a quality flag is added to each numerical value, but the values themselves are not modified. The chosen flag scale is simple and already used in other international projects. The flags are then validated or corrected manually, taking in consideration the overall coherence of the data within the cruise, which is somehow subjective but not arbitary. The automatic checks are made by using pre-existing knowledge of the region: extreme values for broad range checks (corresponding to high error level) and previous climatological profiles for narrow range checks; there is also some subjectivity in the tuning of these parameters.
Specific software is on UNIX (SCOOP) at SISMER and HNODC, which is described herebelow. It is expected not to get any flag different from 1. In case of outlier, the originator will be contacted to see where is the problem and if the data point has to be corrected or rejected.
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Flag Scale
The flag scale is the flag scale adopted by the IOC for the GTSPP International program of temerature exchange in real time. The flag value if documented, is proportional to the level of error. When the data are displayed on a screen for visual checks, a color is assigned to each flag which are the following:
0 : No QC
1 : Correct
2 : Inconsistent
3 : Dubious
4 : Faulse
5 : Modified
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Check of the format, QC-0
This check include the completeness of the documentation like ship name and code etc. Requested corrections or completion are made before any further control.
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Check of the Headers: date and location, QC-1
The following tests are performed automatically first and the results displayed on a screen to perform the manual check. As theese checks concerns location and date, they may be followed with a correction (C) in case of obvious errors. If this is not the case, the profile is eliminated (E) with a global flag to 4(false) (C).
TEST RESULT FLAG VALUE
no outlier 1
1.1: Check for duplicates E
1.2: Check the date C or E 5
1.3: Check the ship velocity C or E 5
1.4: Check the location/shoreline C or E 5
1.5: Check the bottom sounding (ETOPO5) C or E 2
1.6: Visualization and manual checks and
validation of the flags (35kb)
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Check of the parameters, QC-2
Theese checks do not modify the observation but only add the quality flags.
TEST RESULT FLAG VALUE
no outlier 1
2.1: Missing pressure E
2.2: Constant value on the vertical 4
2.3: Impossible regional values(min & max.) 4
2.4: Check the increasing reference (pressure) 4
2.5: Data point below the bottom depth 4
2.6: Check for spikes 3
2.7: Compare with the pre-existing statistics (LEVITUS, MODB) 2
2.8: Check the vertical stability 4
2.9: Visualization and manual checks and
validation of the flags (33kb)
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Regional Parametrisation
Geographical sub-domains
Broad Range Control Values for Observed Parameters
Temperature Control Values
Salinity Control Values
Oxygen Control Values
Geographical sub-domains
The Mediterranean is a very contrasted region from the Black Sea to the Gibraltar Straits and the same control values cannot be used everywhere. For simplicity, Mediterranean Sea has been subdivided in rectangle geographical sub-domains (15kb) whose geographical limits and maximum depth values are the following:
CODE REGION/SUB-DOMAIN LATITUDE LONGITUDE MAX. DEPTH
DF1 ALGERIAN BASIN NORTH N42 00.00 N39 18.00 E004 30.00 E009 18.00 2900
DF2 GULF OF LIONS N43 36.00 N42 00.00 E002 48.00 E006 18.00 2732
DF3 LIGURIAN SEA WEST N44 30.00 N42 00.00 E006 18.00 E009 24.00 2964
DF4 LIGURIAN SEA EAST N44 18.00 N42 48.00 E009 24.00 E010 48.00 1632
DH1 AEGEAN SEA N41 12.00 N35 15.00 E022 30.00 E027 18.00 4500
DH2 CRETAN PASSAGE N35 15.00 N31 00.00 E022 30.00 E027 18.00 4220
DH3 LEVANTINE BASIN N37 04.00 N30 42.00 E027 18.00 E036 30.00 4620
DI1 SARDINIA STRAIT N39 18.00 N36 48.00 E008 24.00 E010 00.00 2857
DI3 SICILIA STRAIT N38 00.00 N36 00.00 E010 00.00 E014 00.00 1585
DJ1 ADRIATIC NORTH N45 54.00 N41 48.00 E012 00.00 E015 48.00 715
DJ2 ADRIATIC MIDDLE N43 54.00 N40 36.00 E015 48.00 E018 08.00 1362
DJ3 ADRIATIC SOUTH N42 48.00 N40 00.00 E018 00.00 E019 48.00 1375
DJ4 IONIAN 1 (NE) N40 00.00 N38 00.00 E018 00.00 E022 30.00 3725
DJ5 IONIAN 2 (SOUTH) N36 00.00 N30 06.00 E010 00.00 E022 30.00 4465
DJ6 IONIAN 3 (NW) N40 36.00 N38 00.00 E016 07.80 E018 00.00 2826
DJ7 IONIAN 4 (MIDDLE) N38 00.00 N36 00.00 E014 00.00 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
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