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Greenhouse Gas Emissions and Dispersion 4. Quality control process of in-situ INFLUX tower-based observation data



Kuldeep R. Prasad, Heming Hu, Israel Lopez Coto, Subhomoy Ghosh, James R. Whetstone


The Indianapolis Flux Experiment (INFLUX) was designed to develop top-down methods for measurement and modeling of urban fluxes of greenhouse gases (GHG) to the atmosphere with spatial and temporal scale of one km. and one hour respectively. A small bias in the observation data relative to the background can introduce significantly large bias in the computed fluxes if it is relatively high to the emission enhancement. Hence, it is important to maintain accuracy of in situ GHG data for unbiased estimation of urban fluxes. Accuracy of GHG observation data can be influenced by quality control (QC) process used for error detection, instrument calibration and error correction. Currently different organizations employ different QC processes on the same raw data resulting in significantly different QC’ed data. This report introduces a standardized approach integrating all present techniques. It consists of four major sequential steps: data screening, gas source based data separation, calibration and time-lag correction, and data averaging. QC’ed data for a set of twelve towers are compared with that from other organization for a period of two months. The influences of different methodologies in the QC process were analyzed, and the important parameters were optimized to reconcile the differences. Finally, recommendations in different phases of QC process are presented to provide guidelines for tower observation.
NIST Interagency/Internal Report (NISTIR) - 8070
Report Number


Quality Control, Greenhouse Gas


Prasad, K. , Hu, H. , Lopez, I. , Ghosh, S. and Whetstone, J. (2015), Greenhouse Gas Emissions and Dispersion 4. Quality control process of in-situ INFLUX tower-based observation data, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed March 4, 2024)
Created September 30, 2015, Updated November 10, 2018