The Aurora Integrating Nephelometer

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The Aurora Integrating Nephelometer
The Aurora Integrating Nephelometer
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What is a Nephelometer?
Nephelometers measure light scattering
(ssp) Light scattering correlates with visibility
and PM2.5 mass measurement Visibility measurement
Lv 3.912 / sext Lv Visibility sext ssp
(scattering) sap (absorption) Correlation with
PM2.5 mass measurement in numerous studies
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Applications of the Nephelometer

• The Nephelometer is an essential addition to any
  monitoring station, providing accurate visibility
  measurements and correlating well to PM2.5 mass
  measurements.
• The Nephelometers other applications are
• Visibility monitoring (Haze, Smog and Fog)
• PM2.5 mass measurement (correlation)
• Dust/Sand storm monitoring (Early Warning)
• Global Warming studies
• Bushfire Monitoring

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Visibility
Accurate information on visible distance Ideal
for Airport visibility measurements Fog, Smog and
Haze measurements Simple measurement that the
wider population can understand (as opposed to
ppm, mg/m3 etc) Provides valuable, extra
information together with

• Gases (O3, NOX, SO2, CO)
• Particulate matter (PM10, PM2.5 in units mg/m3)

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PM2.5 Mass Measurement Correlation

• The Aurora Nephelometer has shown high
  correlation with PM2.5 mass measurement in
  numerous studies.
• PM2.5 concentration directly affects human
  health
• Monitor industrial and automotive pollution in
  the air
• Includes VOCs in measurement (lost in other
  instruments)
• Three Wavelength version provides extra
  information on possible sources of PM2.5

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Dust/Sand storm Monitoring

• The Aurora Nephelometer can be used to monitor
  the origin of dust and sand storms or as an early
  warning tool
• Used in conjunction with meteorological
  stations, Nephelometers can detect the
  direction and possible origin of sandstorms
• A Network of Nephelometers can detect
  sandstorms in real-time and calculate how long
  until storm reaches cities
• Three wavelengths provide extra information on
  sources of dust/sand

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Dust/Sand storm Monitoring
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Global warming studies

• The Three Wavelength Aurora Nephelometer is used
  to measure light scattering and its affects on
  Global radiation balance.
• Uses backscattering to measure reflection of
  light back into atmosphere
• Use of all three wavelengths gives angstrom
  exponent
• Low maintenance and low power makes it useful
  in remote areas for wider ranging studies

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Bushfire Monitoring

• The Aurora Nephelometer can be used for both the
  measurement of pollution from bushfires or as
  part of an early warning network
• Nephelometers can continuously measure
  particulate matter during high concentrations
  events, unlike filter based particulate
  monitors
• A network of Nephelometers can detect location
  and path of bushfires in real time providing
  valuable information

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How does it work?

• The Aurora samples air through a vertical inlet
  and the sample air is illuminated by the light
  source and a photomultiplier detects the
  scattering
• The three wavelength version has a multiple array
  of LEDs which consecutively measure the sample
  thereby getting a slightly different picture of
  the particulate matter
• 450nm (blue) interacts strongly with fine and
  ultrafine particulates (e.g. wood fires,
  automobiles)
• 520nm (green) most sensitive wavelength for the
  human eye (e.g. visibility, smog, fog, haze)
• 700nm (red) interacts strongly with large
  particulate matter (e.g. pollen, sea salt)

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Advantages of the Aurora

• Compared to TSI Nephelometer
• Lower cost of ownership
• Smaller in size
• Lower power consumption (Low carbon footprint)
• Less maintenance and easy operation

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Advantages of the Aurora

• Compared to TEOM
• Lower cost of ownership
• Doesnt miss VOCs (without heater)
• Lower power consumption (Low carbon
  footprint), ideal for remote locations
  (Battery power option)
• Low maintenance and easier to operate
• Can measure high concentration (no filter)
• Vibration insensitive

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Case Studies

• CMA Sand Storm Monitoring
• Centre for Atmosphere Watch And Services (CAWAS),
  CMA
• CMA has deployed 22 Nephelometers Stations in
  rural China Provinces.
• Additionally just purchased 18 extra
  nephelometers to increase monitoring
• Early warning system for approaching dust storms
• Provides aerosol scattering data for numerical
  forecasting of dust storms as well as
  fingerprinting particulate sources (clean vs.
  polluted)

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Case Studies

• Puget Sound Clean Air Agency
• Leader in the United States for Nephelometer
  Ambient Air monitoring
• Used in conjunction with other PM2.5 measurement
  devices
• Accurate monitoring of wood fire stove use
  (particulates)
• Detects rapid changes in particulate pollution
  accurately
• Provides additional visibility measurement
  parameter

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