TITLE: In-situ tower greenhouse gas data (The Pennsylvania State University)
PROJECT: Indianapolis Flux Experiment (INFLUX)
DATES: September 2010 – current
ABSTRACT: The Indianapolis Flux Experiment (INFLUX) was designed to develop and evaluate methods for the measurement and modeling of greenhouse gas fluxes from urban environments. Determination of greenhouse gas fluxes and uncertainty bounds is essential for the evaluation of the effectiveness of mitigation strategies. The current INFLUX observation network includes twelve in-situ tower-based, continuous measurements of CO2, CO, and CH4 (although not all species will be measured at all sites), flask sampling of 14CO2 and other trace gases, and periodic aircraft sampling of greenhouse gases and meteorological conditions. A total carbon column observing network (TCCON) column remote sensing station was deployed Aug – Dec 2012. Four of the tower sites include eddy covariance and radiative flux measurements, and a scanning Doppler lidar is located near Site 02. The data from the towers, TCCON, and aircraft measurements are being used in an inverse-modeling approach to yield estimates of the urban area flux at 1 km2 resolution. Additionally, very high space/time resolution estimates of fossil fuel carbon emissions (Hestia project) offer state-of-the-art “bottom up” emissions estimates for the city and its surroundings.
COMMENTS: Measurements are made with Picarro Inc. wavelength-scanned cavity ring down spectroscopic instruments at multiple levels. Hourly averages are reported here, with the minimum and maximum time included in the average indicated. The standard deviation within the averaging window is also reported. All sites measuring CO are dried using a Nafion dryer and a dry air source for purge. As of late May 2013, all sites are dried. A zero-offset correction is applied daily, using data collected from 1 or 2 NOAA-calibrated tanks. A round robin test using 3 NOAA-calibrated tanks was conducted in November 2013. Results were then used to field calibrate (slope and intercept) the instruments.
COLUMN HEADERS: Location(Site number), Height (m AGL), Time (minimum fractional day of year of the measurement, GMT), Time(maximum fractional day of year of the measurement, GMT), Year, DOY(day of year), Hour(GMT), CO2(dry mole fraction, ppm), Standard_Deviation(during measurement, ppm), Instrument_CO2_Uncertainty(ppm), CH4(dry mole fraction, ppb), Standard_Deviation(during measurement, ppb), Instrument_CH4_Uncertainty(ppb), CO(dry mole fraction, ppb), Standard_Deviation(during measurement, ppb), Instrument_CO_Uncertainty(ppb).
STANDARD DEVIATION: The atmospheric variability is characterized by the standard deviation during the reported measurement period.
UNCERTAINTY: In lieu of a full assessment of the total uncertainty as it changes in time, the instrument uncertainty is characterized by the standard deviation of the reference gas error for a 31-day period (including 15 days prior to the measurement day and 15 days following the measurement day). For more details, please see Richardson SJ, Miles NL, Davis KJ, Lauvaux T, Martins DK, Turnbull JC, et al.. Tower measurement network of in-situ CO2, CH4, and CO in support of the Indianapolis FLUX (INFLUX) Experiment. Elem Sci Anth. 2017;5:59. DOI: http://doi.org/10.1525/elementa.140
FAIR USE POLICY:
We reserve the right to make corrections to the data based on scientific grounds, e.g., recalibration of standard gases or discovery of operational issues not known at the time of the release. If the data are obtained for potential use in a publication or presentation, kindly inform Penn State personnel (email@example.com) of the nature of this work.
Citations: Richardson SJ, Miles NL, Davis KJ, Lauvaux T, Martins DK, Turnbull JC, et al. Tower measurement network of in-situ CO2, CH4, and CO in support of the Indianapolis FLUX (INFLUX) Experiment. Elem Sci Anth. 2017;5:59. DOI: http://doi.org/10.1525/elementa.140
Miles, N.L.,S.J. Richardson, K.J. Davis, and B.J. Haupt, 2017. In-situ tower atmospheric measurements of carbon dioxide, methane and carbon monoxide mole fraction for the Indianapolis Flux (INFLUX) project, Indianapolis, IN, USA. Data set. Available on-line [http://datacommons.psu.edu] from The Pennsylvania State University Data Commons, University Park, Pennsylvania, USA. http://dx.doi.org/10.18113/D37G6P.
To access the data, please go to the PSU Data Commons, keyword INFLUX. Thanks!
(last updated 20 December 2017)