Quality Assurance of Real-Time Data

February 2004

CCOASTALOASTAL DDATAATA IINFORMATIONNFORMATION PPROGRAMROGRAM

1975 - present

Nowcast Model Products

Real-Time Web Products

Southern CaliforniaSummary Map

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

QUALITY ASSURANCEPressure Sensor Calibration

DEEP TANKSoak complete package

(sensors & cable) – Establish noise floor

COLD BOX

•Constant Temperature

•Standard Paros

•Battery of statistical test of dynamic pressure responses over several weeks to establish noise floor.

Generated from Aceh, Indonesia earthquake on Dec 26, 2005 @ 00:59UTC.

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

Quality Control SpecificationsWave Buoys: Frequency Domain

• Check Factors Test – ratio of vertical to horizontal displacement

• Inclination Test• Period exceedence TestQuality of Telemetery: • Discontinuities in transmission• Data Corruption

Central Computer Automated Real-Time Processing

Time Domain Quality Control

Time Series

Frequency Domain

STORAGE rawspectralparameters

WEB UPDATEReal-Time/Historical

Pub/Non-Public

NWS/NDBC Transmission

Station Specific Requests

Error/Diagnostic Statistics

Post Processing Inter-comparison of last

24 hours

PRODUCTS

-106 01 07/11/2003 20:19:30 hrs UTC code=551: (bdd_editor.f) Tp out of bounds: 33.33

Waimea Buoy, HA – Frequency Domain QC

106: First indicated bad by TP errors > 30s

BAD – Energy in Low Frequency for all records

Flagged as NON-PUB 7/11/03

Scripps Canyon NorthWest BuoyScripps Canyon NorthWest BuoyFrequency Domain QC Check factor values 114 01 08/16/2003 00:39:30 hrs UTC code=500: (bdd_editor.f) Abnormally high check factors (relationship between vertical and horizontal cross-spectra)

Direction & Period erratic. Retrieved buoy and performed calibration tests.

Calibration Test – Bad displacement

Wave Wave DataData

Torrey Pines Inner –

20m deep

Torrey Pines Outer –

549m deep

Buoys approximately 6 miles apart

Dana Point Buoy, CADana Point Buoy, CA

First indicated bad by inclination errors (> 5°)• 096 01 09/13/2003 18:59:30 hrs UTC

code=702: (buoy_stats.f) Inclination off, arch: 58.52 file: 52.73

GOOD DISPLACEMENT PLOT BAD – Exagerrated Horizontal Amplitude

Modeling Waves Across the BasinModeling Waves Across the BasinHeadland shadowingHeadland shadowing

Island Island shadowingshadowing

DiffractionDiffractioneffectseffects

Amplification over shoals

RefractiveeffectsDirectional Directional

wave buoywave buoyto initiateto initiatemodelmodel

Pacific Gas & Electric Company Diablo Canyon Nuclear Power Plant

2004

CDIP In-House DiagnosticsCDIP In-House Diagnostics• Paged:

– off site (GPS & ARGOS)– data is > 1 hr old,– computer system is down, – computer partitions are > 90% full.

• Programmers emailed : – Offsite– Data > 1 hr old, power outages, data transfer failedSystem messages

CDIP Diagnostics2004- 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%

http://cdip.ucsd.edu