Quality Control of Minerals Management Service - Oil Company ADCP Data at NDBC: A Successful Partnership Implementation

摘要

The Minerals Management Service (MMS) requires that deep water oil drilling and production platforms in the northern Gulf of Mexico collect and provide current profile data to the National Data Buoy Center (NDBC). NDBC processes and displays the resulting currents on the NDBC website. NDBC has recently implemented quality control algorithms agreed upon by industry and the government-The resulting imagery and data, including quality control flags, are available on the publicly available NDBC website. The quality control algorithms and flags are presented and comparisons of the resulting files are described. Oil companies must collect current profile data when drilling wells or operating production platforms in water greater than 400 meters deep. They are required to collect the data at 20 minute intervals and transmit the data via FTP to NDBC. The data are received, decoded, and quality controlled at NDBC. The current profiles are then formatted in TEmperature Salinity and Current (TESAC) messages and transmitted over the Global Telecommunications System (GTS). The data are also viewed over the NDBC website as columnar listings and current vector stick plots. In order to determine the quality control algorithms for the current profiles, a committee of oil company, industry, and government representatives determined an approach that includes both individual bin (depth level) and profile algorithms. The algorithms take advantage of the fact that the Teledyne RDI Acoustic Doppler Current Profiler (ADCP) collects error velocity, percent good statistics for 3 and 4 beams, and correlation matrices and echo amplitudes for each beam. The algorithms described in this presentation were then implemented and flags generated for each quality control test. A total of nine flags are assigned within the NDBC database. The flags indicate good data (3), suspect data (2), or bad (1) data. Only bad data are not reproduced or plotted on the NDBC real-time webpage. Results from the implementation are being reviewed, but a quick look indicates that the algorithms are returning accurate descriptions of the ADCP data. The stick plots of ocean current with depth are much "cleaner" following the quality control implementation. The implementation of the quality control algorithms was delayed by Hurricanes Katrina and Rita, which impacted both the NDBC and the oil industry in the Gulf of Mexico. NDBC is now resubmitting past data files through the quality control algorithms to insure that all data at NDCB have been quality controlled. The results of this effort (including the quality control algorithms) are being shared with Integrated Ocean Observing System (IOOS) partners in an effort to standardize quality control of oceanographic data.