sismer systèmes d’informations scientifiques pour la mer f-nodc
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SISMER Systèmes d’Informations Scientifiques pour la Mer F-NODC. Quality Control Procedure at IFREMER Argo data management meeting Brest 03-05/10/2000. 2. 5. 9. 1. 3. 4. 0. No QC. Correct. Inconsistent. Changed. Missing. Doubtful. Bad. Quality Checks : Automatic + Visual. - PowerPoint PPT PresentationTRANSCRIPT
TMSI/IDM/SISMER Sept 2000
SISMERSISMER Systèmes d’Informations Scientifiques pour la Mer F-NODC
Quality Control Procedure at IFREMER
Argo data management meeting
Brest 03-05/10/2000
2
Quality Checks : Automatic + VisualQC0 : Format, Codes, Completeness of InformationQC1 : Date, Time, Location, DuplicatesQC2 : Data PointsResult : Elimination or Quality Flag from GTSPP Scale
References UNESCO/COI/IODE : Manual of Quality Control Procedures for validation of
Oceanographic Data - Manuals and Guides 26 - (GTSPP chapter) ICES -GETADE Formatting Guidelines for Oceanographic Data Exchange
(http://www.ices.dk/ocean/) ICES -MDM QA Guidelines - CTD - Marine Data Management working Group (CIEM)
Reports UNESCO/IOC/IODE : GF3 A General Formatting System for Geo-Referenced Data -
Manual and Guides 17
0 1 2 3 4 5 9No QC Correct Inconsistent Doubtful Bad Changed Missing
3
QC0 - FORMATS, CODES, INFORMATION
Check of Meta-Data/Information : RDBS - ORACLE
Present Input Format for full QC : autodescriptive ASCII (MEDATLAS) NetCDF (in preparation) Other input formats (Via conversion interfaces)
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QC1 Control of the location and Date - Data collected in station
Automatic Checks Results - Flag
Duplicate data sets EliminationDate Elimination or 5 Ship/Platform velocity Elimination or 5Location/shoreline Elimination or 5Bottom sounding (ETOPO5) Elimination or 3
5 = Correction/Interpolation 3 = doubtfull depth
5
QC2 - Control of the Data points
Automatic Checks Results/Flag
Pressure record only EliminationOut of the regional scale 4 (min & max values)Non Increasing pressure 4Data below the bottom depth 4Coherence with pre-existing statistics (LEVITUS, REYNAUD, MEDATLAS) 2
Constant profiles 4Spikes - Gradient 3Vertical instability > noise 4
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QC2 - Control of the Data pointsMinimum & Maximum - Broad Range Check
0
200
2000
6000
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QC2 - Control of the Data pointsRegional Adjustment for Broad Range Checks
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QC2- Vertical Stability Check
Threshold noise for instability detection 0.03 in sigma-t for high resolution deep water
stations 0.05 to 0.1 for coastal or low resolution stations
4 data points to be checked : 2 levels T, S Automatic seach for further anomaly
if any flag=4 at this point if none flag=4 at the 4 points and manual
decision
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QC2 - Spike and Gradient Checks
On 2 consecutive points at the top and bottom On 3 consecutive points in between Threshold for detection adjustable in geographical
subregions and vertical layers
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QC2- Climatological Checks
Several available climatologies : Levitus 94, 98, Reynaud, Medatlas, MODB
Default Climatology is Levitus 98 1x1 degree Allowed Variability
Shallow water stations bottom < 100 m : 5 standard deviations
Shelf Stations 200< bottom < 400 : 4 standard deviations
Deep Stations bottom > 400 m : 3 standard deviations
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Visual Checks Check of the Internal Coherence
QC1 : Check of the route or trajectory QC2 : Internal coherence of the values and search for shifts or
gaps Check of the External Coherence
QC1 : Display of all the profiles of another cruise/trajectory if at least one station is in the space/time vicinity
QC2 : Possibility of superposing the profiles made during another experiment in the same region
Removing Doubts Vertical intabilities Spikes Climatological test (Erroneous climatological standard deviations)
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QC1 Control of the location and Date VISUAL CHECKS - Data collected in station
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QC1: Control of the location and Date - Time series on fixed mooring
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QC2 - Control of the Data pointsVisual Checks
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QC2 - Control of the Data pointsVisual Checks - case of problematic climatology