Nephelometers

• Full Name: Integrating Nephelometer

• Short Name or Acronym: Neph

• Measurements Provided: Light scattering extinction coefficient at 530 nm wavelength. Sample air temperature, pressure, relative humidity

• Manufacturer or Builder of the Instrument: Radiance Research

• Operational Status:

  • requestable, ready for deployment

• General Description:

  • The nephelometer measures light extinction integrated over a wide range of scattering angles, ~0 to 180 deg, at a single-wavelength. Extinction varies with aerosol loading, particle composition and humidity. Two identical instruments are available, and can be used simultaneously. Sample air can be divided so that one unit samples at ambient humidity, and the other measures air that passes through a humidifier controlled at 90% RH. Nephelometers require an air sample inlet, tubing and a pump or other source of suction.

• Measurement Characteristics:

  • Overall estimate of uncertainty: see references
  • Response time: ~5 to 10 sec, depending on flow rate

  • Precision: Extinction range 0.001 to > 1 km^-1; also see references

  • Other measurement characteristics (comments on signal/noise, bias limits, etc):

• Lead Contact: Dave Rogers

Documentation

• Descriptive Publications

• Heintzenberg, J., and Coauthors, 2006: Intercomparisons and Aerosol Calibrations of 12 Commercial Integrating Nephelometers of Three Manufacturers. J. Atmos. Oceanic Technol., 23, 902–914. doi: http://dx.doi.org/10.1175/JTECH1892.1

• Documentation of the Processing Algorithm(s): See the Technical Note on Processing Algorithms at this URL (fix when available)