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QC Procedures at INCOIS. TVS Udaya Bhaskar, CLIVAR(GSOP), 12 - 14 th June, 2013. Type of Data sets. Argo data from Indian and non-Indian floats. CTD data from Indian ORV. XBT/XCTD data from National Institute of Oceanography (NIO), Goa.
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QC Procedures at INCOIS TVS Udaya Bhaskar, CLIVAR(GSOP), 12 - 14th June, 2013
Type of Data sets • Argo data from Indian and non-Indian floats. • CTD data from Indian ORV. • XBT/XCTD data from National Institute of Oceanography (NIO), Goa. • Specific Project related data viz., ARMEX, BOBMEX, ICRP etc. • Time series data also available. • Moorings, Drifters, Current Meter Arrays, ADCPs etc.
QC procedures • For CTDs and Argo floats • Automatic QC as proposed by ADMT • Three-way-QC • Automatic QC, • QC based on Objective Analysis • Visual Quality Control Tool • Cluster based • Latitude, Longitude based clusters • For XBT/XCTDs • QC is performed at NIO, Goa • Planning to use Mquest by CSIRO.
CTD Profiles RTQC (18 checks) Assign quality flag Objective Analysis Bulls eye Others Visual QC (adjust flags) Data-base
Visual Quality Control of Argo/CTD data • Visual Quality Control Tools is used for QC of Argo data. WOA05 is used in the background for the QC process. • Profiles falling out of 3*sigma are set as bad. T&S Profiles (Argo Floats, XBT, XCTD, CTD)
Quality control of oceanographic data sets based on spatio-temporal clustering • Clustering method with recent WOA09 climatology. • Tested for all standard levels • Sensitivity studies were done.
QC based on Lat/Lon Clusters • Climatological mean and standard deviation are used to build n-sided (dimensional) polygon. • Outliers are detected based by judging whether the points are falling with in the polygon or out side. • These are re-examined for any special events and then injected into the database.
Good point Outlier The n-sided polygon is used for checking outliers. Now the data points whose quality is to checked are introduced and checked whether the points fall with in the n-sided polygon (good points) or outside the polygon (bad points).
Depth 10 m Outliers Outliers Latitude (deg)
Persian Gulf Red Sea Outliers BOB