1. Initial Automated Quality Checks for Oil Platform Current Data Don Conlee, Richard Bouchard, Steve Collins and Dave Gilhousen National Data Buoy Center Stennis Space Center, MS 39529 Cortis Cooper ChevronTexaco San Ramon, CA 94583

2. NTL Background NTL – Notice to Lessees –First Issued November 24, 2004 –Revised January 7, 2005 –Implementation Date 31 March Next Revision will require 15 April implementation Requirements –Deep water (400m) production facilities and mobile drilling units –Monitor and report in real-time currents from 30 to 1000m Every 16m, 20 min. averages –Delayed mode reporting for near bottom currents when deeper than 1100m –Report to a publicly accessible website MMS Asked NDBC to be website/distributor (January meeting) Rapidly evolving!

3. Process Overview Operators encode data in modified RDI binary format with header FTP to NDBC NDBC display and provide data via website, insert to GTS, OpenDAP

4. NDBC Role and Implementation Single Station Data Display and Distribution –No value-added products Phased Implementation –Phase 1: Decode and Display/Distribute on Web –Phase 2: QA/QC, GTS TESAC encoding, Delayed Mode processing, Log Files, Emails for missing data, Monthly reports to MMS –Phase 3: OpenDAP and Cleanup Open Issues –Mesh profiles? (multiple instruments) –Level of QC

5. Initial QA/QC Operators, MMC, RDI and NDBC Teleconference Reference: RDI Memorandum of 7 Feb. 05 38 Khz and 75 Khz only, External Power Single-profile based Two-Tier Approach –Thresholds at Each Bin –Overall Profile Internal Built-In Test (BIT)

6. Initial QA/QC, cont. PassSoftFlagHard Flag Error Velocity< 15 cm/sec15-30 cm/sec>30 cm/sec Percent Good38: >25% 75: >10% 38: 22-25% 75: 5-10% 38: <22% 75: <5% Correlation Magnitude (counts) 38: 3 beams > 110 75: 3 beams > 64 38: 2 beams > 110 75: 2 beams > 64 38: 1 beam >110 75: 1 beam > 64 Echo Intensity (After 15 th bin) No adjacent bin differences >20 Adjacent bin differences 20-30 Adjacent bin differences >30 Vertical Velocity (each bin) Departure from mean <5 cm/sec Departure from mean 5-10 cm/sec Departure from mean >10 cm/sec Horizontal Velocity <1.25 m/sec1.25-2.5 m/sec>2.5 m/sec

7. Initial QA/QC, Cont. Tier 2 Processing –Pass: All bins passed all Tier 1 tests –Soft Flag: Less than half bins flagged –Hard Flag: More than half bins flagged NDBC Flag Implementation (proposed) –Flag and release all data via web –Do not release Hard-Flagged data to GTS in TESAC code

8. Follow-on QC Efforts Adapt strategy to higher frequency (and battery powered) ADCPs, and all ADCP data processed by NDBC –Large ADCP expansion underway at NDBC Time continuity and other processing dependent on previous report Spatial Checks Model Comparisons? Training of NDBC DAC Staff for Man/machine QA/QC Issue: Level of QC for MMS data may require extensive human effort: role for value-added providers?

9. Questions? Contact Info: Don T. Conlee, Ph.D. Chief Scientist National Data Buoy Center Stennis Space Center, MS 39529 don.conlee@noaa.gov 228-688-1753