Observations of CO2, CH4, and CO mole fractions from the NIST Northeast Corridor urban testbed

NOTE: please see the latest (March 2025) update at https://doi.org/10.18434/mds2-3765 . This archive is from November 2021.We have become aware of errors in the inlet heights at multiple sites and have corrected these in the newest version. Hourly observations of CO2 and CH4 from tower-based sites in the NIST Northeast Corridor network; CO observations from one site. Data files are comma delimited (CSV). Measurements of each species may be from two or more different heights above ground. Site locations, heights, and other information is in a separate ascii (CSV) file (NEC_sites.csv). Data in this archive is reported for the years 2015-2020. An ASCII Readme file (NEC_Readme_11012021) is also posted, along with an Updates_11012021.txt file that includes information on updates. In this update, we added a new directory with Obspack-formatted text and netcdf files for users familiar with those data formats (https://gml.noaa.gov/ccgg/obspack/), and have added Kenneth Schuldt (NOAA-GML and CIRES), who generated this ObsPack, to the data citation. These files include all years 2015-2020. Note about calibrations: CO2 data are reported on the NOAA/WMO X2007 calibration scale. CH4 data are reported on the NOAA/WMO X2004A calibration scale; CO data, where available, are reported on the NOAA/WMO X2014 scale. This archive, with CO2 data on the X2007 scale, will no longer be updated. A full revision of all the data on the NOAA/WMO X2019 scale for CO2 is forthcoming, and will be linked here; that archive will maintain its own record and DOI, include CH4 and CO, and will be continually updated. This data is being freely distributed for research, academic and related non-commercial purposes consistent with NIST's mandate to further the science and the promulgation of appropriate standards.Current update: Nov 1, 2021.