Measurement : Visibility

The greatest horizontal distance in a given direction at which it is just possible to see and identify with the unaided eye (a) in the daytime, a prominent dark object against the sky at the horizon, and (b) at night, a moderately intense light source.

Categories
Atmospheric State

Instruments

The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes.

  • ARM Instruments
    • MET : Surface Meteorological Instrumentation
    • METTWR : Surface and Tower Meteorological Instrumentation at NSA
  • External Instruments
    • MOLTS : Model Output Location Time Series
    • NOAASURF : NOAA Surface Meteorology Data, collected by NWS and NCDC
    • RUC : Rapid Update Cycle Model Data
  • Field Campaign Instruments
    • NOAASURF : NOAA Surface Meteorology Data, collected by NWS and NCDC
    • MET : Surface Meteorological Instrumentation

Datastreams

  • METTWR : Surface and Tower Meteorological Instrumentation at NSA Datastreams
    • PWS : Present weather sensor, 1-min avg
    • METTWR2H : Meteorological tower with 2 sampling heights (2 and 5 m)
  • MET : Surface Meteorological Instrumentation Datastreams
    • MET : ARM-standard Meteorological Instrumentation at Surface
  • RUC : Rapid Update Cycle Model Data Datastreams
    • RUC20ISOB : Rapid Update Cycle (RUC) model: daily isobaric analysis data, 20 km resolution
    • ALLRUC20ISOB : Rapid Update Cycle (RUC) model: isobaric main analysis data, 20-km resolution
    • ALLRUC40ISOB : Rapid Update Cycle (RUC) model: isobaric main analysis data, 40-km resolution
    • SYNRUC20ISOB : Rapid Update Cycle (RUC) model: isobaric output, 20 km grid, averaged to 40 km
  • NOAASURF : NOAA Surface Meteorology Data, collected by NWS and NCDC Datastreams
    • 60NWSSURF : National Weather Service (NWS) surface meteorology data: 60-minute averages
  • MOLTS : Model Output Location Time Series Datastreams
    • MOLTSEDASSFCCLASS1 : Model Output Loc. Time Ser. (MOLTS): EDAS meteor. analy., enhanced surface, params, stations