Quality Assurance of Real-Time Data

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COASTAL DATA INFORMATION PROGRAM 1975 - present

• Quality Assurance of Real-Time Data
• February 2004

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Real-Time Web Products
Southern California Summary Map
Nowcast Model Products
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1995 Wave Data Standards Analysis US Army
Corps of Engineers provide specifications on
the analysis techniques that must be applied to
wave data .to ensure quality and uniformity of
the final product. The standard has evolved
through a consensual approach involving the
principal organizations which are responsible
for the vast majority of wave measurements for
this country. 2003 Handbook of Automated Data
Quality Control Checks and Procedure of the
National Data Buoy Center
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QUALITY ASSURANCEPressure Sensor Calibration

• COLD BOX
• Constant Temperature
• Standard Paros
• Battery of statistical test of dynamic pressure
  responses over several weeks to establish noise
  floor.

• DEEP TANK
• Soak complete package (sensors cable)
• Establish noise floor

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Generated from Aceh, Indonesia earthquake on
Dec 26, 2005 _at_ 0059UTC.
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Quality Control SpecificationsPressure Sensors
Time Domain

• Max Wave Height Test
• Flat episodes Test
• Spike Test
• Max value Test successive trough to crest
• Min Value Test successive trough to crest
• Mean Shift Test
• Equal Peaks Test
• Acceleration Test
• Mean crossing Test
• Period Distribution Test

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Quality Control SpecificationsWave Buoys
Frequency Domain

• Check Factors Test ratio of vertical to
  horizontal displacement
• Inclination Test
• Period exceedence Test
• Quality of Telemetery
• Discontinuities in transmission
• Data Corruption

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Central Computer Automated Real-Time Processing
Time Series
Time Domain Quality Control
Frequency Domain
PRODUCTS
NWS/NDBC Transmission Station Specific Requests
WEB UPDATEReal-Time/Historical Pub/Non-Public
STORAGE rawspectralparameters
Error/Diagnostic Statistics
Post Processing Inter-comparison of last 24
hours
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-106 01 07/11/2003 201930 hrs UTC
code551 (bdd_editor.f) Tp out of bounds
33.33
Waimea Buoy, HA Frequency Domain QC 106 First
indicated bad by TP errors gt 30s
Flagged as NON-PUB 7/11/03
BAD Energy in Low Frequency for all records
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Scripps Canyon NorthWest BuoyFrequency Domain
QC Check factor values 114
01 08/16/2003 003930 hrs UTC code500
(bdd_editor.f) Abnormally high check
factors (relationship between vertical and
horizontal cross-spectra)
Calibration Test Bad displacement
Direction Period erratic. Retrieved buoy and
performed calibration tests.
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Wave Data
Torrey Pines Inner 20m deep Torrey Pines
Outer 549m deep
Buoys approximately 6 miles apart
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Dana Point Buoy, CA

• First indicated bad by inclination errors (gt 5)
• 096 01 09/13/2003 185930 hrs UTC code702
  (buoy_stats.f) Inclination off, arch 58.52 file
  52.73

GOOD DISPLACEMENT PLOT
BAD Exagerrated Horizontal Amplitude
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Modeling Waves Across the Basin
Headland shadowing
Refractive effects
Directional wave buoy to initiate model
Island shadowing
Diffraction effects
Amplification over shoals
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Pacific Gas Electric Company Diablo Canyon
Nuclear Power Plant
2004
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CDIP In-House Diagnostics

• Paged
• off site (GPS ARGOS)
• data is gt 1 hr old,
• computer system is down,
• computer partitions are gt 90 full.
• Programmers emailed
• Offsite
• Data gt 1 hr old, power outages, data
• transfer failedSystem messages

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CDIP Diagnostics
2004- Data Collection Coverage Percentages -------
-------------------------- La Jolla
99.89 Torrey Pines O 95.29 San Pedro
95.24 Santa Monica 99.64 Pt Dume
95.88 Goleta 97.06 Harvest 94.70 Pt. Reyes
91.88 Grays Harbor 99.31 Guam 99.72
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http//cdip.ucsd.edu