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.
UNCERTAINTY: The atmospheric uncertainty is characterized by the standard deviation during the reported measurement period. 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).
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).
REQUEST INFLUX TOWER DATA ACCESS VIA AN EMAIL TO CO2DATA@meteo.psu.edu. Include your name, affiliation, and intended use. Please keep PI’s informed about any publication plans.
FAIR USE POLICY: Permission to download this data does not grant permission to use the information contained in that data for publication or any commercial use. Please request permission by e-mailing the Penn State group (email@example.com) before any commercial use or publication. If you have any questions about the use of these data or the Fair Use policy, please contact a member of the group at firstname.lastname@example.org.
PLEASE DO NOT DISTRIBUTE THESE DATA.
(last updated 10 October 2014)