Data quality control and quality assurance practices for Ocean Networks Canada observatories

Cabled observatory installations permit the acquisition of large volumes of continuous, high-resolution data from in-situ instruments. This type of data acquisition presents new challenges and opportunities in the development of data quality assurance and quality control (QAQC) measures. Ocean Networks Canada (ONC) operates the world-leading NEPTUNE and VENUS cabled ocean observing systems in the NE Pacific, and a small seafloor observatory in the Canadian Arctic. ONC collects high-resolution, real-time data on physical, chemical, biological, and geological aspects of the ocean over long time periods, supporting research on complex earth and ocean processes with innovative methods. High quality research depends on high quality data, which in turn depends on robust data quality control practices. For the data to be useful to potential end users, they must be qualified under accepted international standards with additional metadata pertaining to methods of measurement, instrument calibrations, and subsequent data processing included. Ocean Network Canada's QAQC methodology presented here has been developed with the key objectives of maintaining consistency within a single data set and within a collection of data sets. The QAQC model also ensures that the end user has sufficient information on the quality and errors of the data to assess its suitability for their use. The data QAQC procedures and tools have the capability to associate distinctly different but related types of information with data to provide a systematic and timely examination of the measurements. Efforts have been taken to develop efficient and accurate data QAQC techniques and tools to ensure quality data delivery to the end users in a timely manner. The large volume of data coming from extremely complex, diverse, and unpredictable ocean environments has resulted in many challenges as well as opportunities to develop efficient and informative tools for data QAQC at ONC. This paper describes the current and future steps that ONC is undertaking to ensure that data delivered by the observatories are of high quality, easily accessible, and reliable.