Print PageThe National Ecological Observatory Network, NEON, will be deploying more than 11,000 sensors, of 44+ different types over a five year construction period, generating over 45 Tb of data per year. In addition, there will be 10’s k of field samples being analyzed by contract laboratories, whose long-term quality control must be managed over our 30-y operational lifespan. In preparation of construction, and follow on long-term operations of the observatory, NEON is developing a new and innovative calibration facility at its HQ (Boulder CO) as well as an outdoor calibration facility (Longmont CO) for sensors, and an audit lab to track contract labs. All calibration facilities will assure the data collected by the NEON project is of the highest quality and allow the data to be comparable to that collected by other entities. Both the scale and number of measurements/samples have not been attempted before by any agency or program. Hence, how will NEON manage the calibration uncertainty, and traceability, for a large scale ecological observatory?
It is the responsibility of the NEON’s calibration laboratory to assure that all sensors and samples are calibrated and traceable to nationally, and internationally recognized standards and procedures. When possible, calibrations will be made against first principles. In addition, the shear mass quantity of calibrations and the importance of data quality have made it apparent, that accounting for all uncertainty factors in each calibration type has to be one of the laboratories main priorities.
Results/Conclusions:
Our design process has focused on how to maintain the traceability and how uncertainty will be managed over 30-y. Here, we present the i) overall strategy for calibration and validation for all our sensors and samples, ii) results from our calibration fixtures, and iii) ISO traceable uncertainty analyses for ecological data.
As such, we report tests that evaluate the uncertainty originating from specific equipment, primary and secondary standards, test setup, user interface, operator, statistical approaches, and the QA/QC process. We report on the optimal calibration procedure for field sensors and transfer standards by direct comparison to a primary standard or through the use of secondary standards. In addition to this evaluation process, we report procedures and design process to remove, minimize and/or account for; human bias, equipment faults, ambient environment changes, data acquisition error and other operational errors. The identification and elimination of uncertainties will be an ongoing task requiring consistent reevaluation and adjustments to optimize policies, procedures, and designs.
