DOI: 10.18434/1503164
title: Carbon Dioxide Mole Fraction Measurements and Model Output in the Northeast Corridor:
      Baltimore/Washington for February 2016

description: Dataset accompanying publication: "Investigating Sources of Variability and Error
      in Simulation of Carbon Dioxide in an Urban Region" Cory R. Martin, N. Zeng, A. Karion, K.
      Mueller, S. Ghosh, I. Lopez Coto, K. Gurney, T. Oda, K. Prasad, Y. Liu, R. Dickerson, and J.
      Whetstone in the Journal Atmospheric Environment DOI forthcoming Data files presented here
      include both carbon dioxide (CO2) mole fraction observations from NIST-Earth Networks tower
      stations in the region surrounding Washington, D.C. and Baltimore, MD and modeled mole
      fractions for these same sites. Please refer to the publication above for all details,
      including locations of sites, and abbreviations of models and site codes. Observations from
      SNP are not included, as they can be obtained from NOAA/ESRL. Model Output Files: All files
      are comma-delimited text files. The filename indicates the site (three letter code: SNP, ARL,
      NDC, HAL), followed by the inlet height above ground (in meters), followed by the name of the
      inventory (Vulcan, ODIAC, ODIACFIX, EDGAR, FFDAS, VEGAS), or Back, indicating the incoming CO2
      mole fraction background. The total modeled CO2 mole fractions, for example, for FFDAS, are
      the sum of Back, VEGAS, and FFDAS tracers. Example: HAL_29_FFDAS.csv contains the CO2 mole
      fraction contribution at HAL at 29m from the FFDAS inventory. The sum shown in the paper is
      HAL_29_FFDAS + HAL_29_Back + HAL_29_VEGAS. Model output files contain two columns: The
      date-time stamp (UTC), and the CO2 mole fraction in micromoles of CO2 per mole of dry air, or
      ppm. Observation Files: CO2 Measurements are reported on the WMO X2007 (CO2) scales. Refer to
      Verulst et al, 2017 for measurement and calibration details. Verhulst, K. R., A. Karion, J.
      Kim, P. K. Salameh, R. F. Keeling, S. Newman, J. Miller, C. Sloop, T. Pongetti, P. Rao, C.
      Wong, F. M. Hopkins, V. Yadav, R. F. Weiss, R. M. Duren and C. E. Miller (2017), Carbon
      dioxide and methane measurements from the Los Angeles Megacity Carbon Project PartÂ 1:
      calibration, urban enhancements, and uncertainty estimates, Atmos. Chem. Phys., 17(13),
      8313-8341, doi:10.5194/acp-17-8313-2017. Each file name is encoded with the site, year,
      revision number and date, as follows: For all sites, all file names follow this naming scheme:
      [site]-[year]-[gas]-[measurement height]-[averaging-interval]-[revision date].csv Example:
      ARL-2016-co2-100m-1-hour-20160504.csv Column Headers (with description) for observation CO2
      files: datetime_UTC (date, dd-mm-yyyy HH:MM:SS) dec_year_UTC (decimal year) yyyy (year) mm
      (month) dd (day) HH (hour, UTC) co2_ppm (dry air mole fraction, ppm, averaged over the hour
      following the time stamp) co2_SD (standard deviation of air data in 1 hour) co2_n_minutes
      (number of 1-minute values in each 1-hour average) co2_min (ppm, minimum 1-min value in each
      1-hour) co2_max (ppm, maximum 1-min value in each 1-hour) co2_uncertainty (ppm, 1-sigma
      measurement uncertainty) co2_flags (data quality flag: "..P" indicates preliminary data, which
      might change if a final calibration is applied at a later date).