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    • In Situ Carbon Dioxide, Methane, and Carbon Monoxide Mole Fractions from the Los Angeles Megacity Carbon Project

    Metadata Updated: July 9, 2025

    NOTE: please see the latest (April 2025) update at https://doi.org/10.18434/mds2-3814 . Hourly observations of carbon dioxide (CO2) and methane (CH4) mole fractions in dry air from tower- and rooftop-based sites in the Los Angeles Megacity Carbon Project network. Carbon monoxide (CO) observations exist at several stations in this network but are not included in this data release pending additional calibration verification. Please contact the authors for higher frequency data, which are available on request. 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 are in a separate ASCII (CSV) file (LAM_sites.csv). Data are currently reported for the years 2015-2023. An ASCII Readme file (LAM_Readme_2024) is also posted. CO2 data are reported on the NOAA/WMO X2007 calibration scale. A full revision on the NOAA/WMO X2019 scale for CO2 is forthcoming, and will be linked here. CH4 data are reported on the NOAA/WMO X2004A calibration scale. Current update: May 17, 2024.

    Access & Use Information

    Public: This dataset is intended for public access and use. License: See this page for license information.

    Downloads & Resources

    Dates

    Metadata Created Date May 17, 2021
    Metadata Updated Date July 9, 2025

    Metadata Source

    Harvested from NIST

    Other Data Resources

    Additional Metadata

    Resource Type Dataset
    Metadata Created Date May 17, 2021
    Metadata Updated Date July 9, 2025
    Publisher National Institute of Standards and Technology
    Maintainer
    Identifier ark:/88434/mds2-2388
    Language en
    Data Last Modified 2021-05-03 00:00:00
    Category Environment:Greenhouse gas measurements
    Public Access Level public
    Bureau Code 006:55
    Metadata Context https://project-open-data.cio.gov/v1.1/schema/data.json
    Schema Version https://project-open-data.cio.gov/v1.1/schema
    Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
    Harvest Object Id c8fd2015-994a-41da-bf30-cba21f7229ad
    Harvest Source Id 74e175d9-66b3-4323-ac98-e2a90eeb93c0
    Harvest Source Title NIST
    Homepage URL https://data.nist.gov/od/id/mds2-2388
    License https://www.nist.gov/open/license
    Old Spatial Southern California, United States
    Program Code 006:047
    Replaces ark:/88434/mds2-2388
    Source Datajson Identifier True
    Source Hash 17f7ea6847c4068dab3a4b0d3b0306aa23cf71b040e90afe41f5b6681907bffe
    Source Schema Version 1.1
    Spatial
    Temporal 2015-01-01/2019-12-31

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