Hourly in-situ aerosol measurements began in the mid-1970s at baseline observatories and expanded to regional stations in 1992. The NOAA Earth System Research Laboratory Global Monitoring Division collects data on light absorption, scattering, backscattering, and particle number concentration. Data are updated several times daily and screened for contamination using wind speed, direction, and particle concentration.
Use Cases
Analyze trends in aerosol light absorption and total scattering to assess long-term climate forcing.
Validate remote sensing retrievals by comparing satellite-derived aerosol optical depth with in-situ hemispheric backscattering and total scattering measurements.
Evaluate model simulations of aerosol behavior using ground-truth data on particle number concentration and optical properties.
Study regional aerosol variability by correlating measured optical properties with local meteorological data like wind speed and direction used in contamination screening.
Strengths
Hourly temporal resolution provides detailed diurnal and seasonal cycles.
Data collection spans from the mid-1970s to present, enabling long-term trend analysis.
Rigorous quality control includes automatic screening using wind speed, direction, and particle number concentration, plus manual review.
Limitations
Specific row count, geographic coverage of stations, and sample size per station are unknown.
Manual contamination screening is described as subjective, potentially introducing analyst-dependent bias.
The dataset's completeness and potential gaps for specific stations or time periods are not detailed.
Provenance
Source
NOAA Earth System Research Laboratory (ESRL) Global Monitoring Division (GMD).
Collection Method
In-situ measurements from nephelometers, absorption photometers, and condensation nuclei counters at baseline and regional monitoring stations.
Time Range
Mid-1970s to present.
Freshness
Data are updated several times a day.
Geography
Global baseline observatories and regional monitoring stations (specific locations unknown).
Data files have been converted to NetCDF-4 format through the Big Earth Data Initiative. License terms are not specified.