{
    "identifier": "gov.noaa.ncdc:C01539",
    "accessLevel": "public",
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        "fn": "Your contact point",
        "hasEmail": "mailto:[email protected]"
    },
    "programCode": [
        "010:000"
    ],
    "landingPage": "",
    "title": "Earth System Research Laboratory Long-Term Surface Aerosol Measurements",
    "description": "Aerosol measurements began at the NOAA Earth System Research Laboratory (ESRL) Global Monitoring Division (GMD) baseline observatories in the mid-1970's with the purpose of detecting a response, or lack of response, of atmospheric aerosols to changing conditions on a global scale. In 1992 ESRL\/GMD expanded its aerosol research program to include regional aerosol monitoring stations due to anthropogenic aerosols creating a significant perturbation in the Earth's radiative balance on regional scales. The goals of this regional-scale monitoring program are to characterize means, variability, and trends of climate-forcing properties of different types of aerosols, and the factors that control them. In situ measurements of aerosol optical properties (including light absorption, total scattering, hemispheric backscattering, and total aerosol number concentration) are made at monitoring sites at hourly time resolution. The basic aerosol measurement system consists of a nephelometer (measures aerosol light scattering), absorption photometer (measures light absorption), and a condensation nuclei counter (measures particle number concentration). Data from the aerosol monitoring stations are updated several times a day. Following collection of the raw data at the station, the data are inspected through automatic and manual contamination screenings to eliminate contamination from local pollution sources. Automatic screenings use measured wind speed, direction, and\/or total particle number concentration to flag contaminated data. Manual screening is more subjective, relying on the station scientist to evaluate the data in the context of automated contamination flags and their knowledge of the site.  \n  \nData applications indicate the importance of continuing to provide long-term aerosol in-situ measurements for use in analysis of trends and climatologies, evaluation of model simulations of aerosol climatologies, and behavior and validation of remote sensing retrievals of aerosol optical properties. GMD's measurements also provide ground-truth for satellite measurements and global models, as well as key aerosol parameters for global-scale models. \n\nThrough the Big Earth Data Initiative (BEDI), ESRL\/GMD has taken their data collection and converted files into NetCDF-4, a self-describing format.",
    "language": "",
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    "bureauCode": [
        "010:04"
    ],
    "modified": "2025-11-20T02:55:20.060Z",
    "publisher": {
        "@type": "org:Organization",
        "name": "Your Publisher"
    },
    "theme": "",
    "keyword": [
        "Earth Science > Atmosphere > Aerosols",
        "Earth Science > Atmosphere > Aerosols > Aerosol Backscatter",
        "Earth Science > Atmosphere > Aerosols > Aerosol Forward Scatter",
        "Earth Science > Atmosphere > Aerosols > Aerosol Particle Properties",
        "Earth Science > Atmosphere > Aerosols > Aerosol Light Scattering Coefficient",
        "Earth Science > Atmosphere > Aerosols > Aerosol Light Absorption Coefficient",
        "Earth Science > Atmosphere > Aerosols > Aerosol Number Concentration",
        "Atmospheric - Composition - Aerosol Properties",
        "Continent > North America > United States Of America > Illinois",
        "Continent > North America > United States Of America > Alaska",
        "Continent > North America > United States Of America > Hawaii",
        "Ocean > Pacific Ocean > Central Pacific Ocean > American Samoa",
        "Continent > Antarctica",
        "Continent > North America > United States Of America > California",
        "Vertical Location > Land Surface",
        "ESRL > Earth System Research Laboratory (NOAA)",
        "NEPHELOMETERS",
        "AEROSOL MONITOR",
        "CNC > Condensation Nuclei Counter",
        "LIGHT ABSORPTION PHOTOMETER",
        "AIR MONITORING STATIONS\/NETWORKS",
        "ESRL STATIONS > NOAA Earth Science Research Laboratory Stations",
        "Point Resolution",
        "Point Resolution",
        "Hourly - HTML Markup Was Removed",
        "DOC\/NOAA\/NESDIS\/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce",
        "DOC\/NOAA\/ESRL\/GMD > Global Monitoring Division, Earth System Research Laboratory, NOAA, U.S. Department of Commerce",
        "climatologyMeteorologyAtmosphere"
    ]
}