Measuring Aerosol Composition

• Characterizations of different sources of aerosols(e.g., biomass burning, automobile combustion, dust, sea-salt, etc.)
• Extent and rates of photochemical aging for emitted plumes
• Quantification and apportionment of column-based aerosol optical depth observations to different particle sources/types
• Quantification of mass absorption/scattering efficiency values which are directly used by regional- and global-scale models to relate emissions optical/climate processes

• Sensitive to sub-micron non-refractory (volatilize at T<600°C) particles
• Size-resolved (60-800 nm diameter)
• High-resolution mass spectra allow elemental analysis (O, C, H)
• Statistical methods to quantify mass concentrations of sulfate, nitrate, organic compounds as well as processing state of organic aerosol.
  http://www.aerodyne.com/products/aerosol-mass-spectrometer
  http://cires.colorado.edu/~jjose/ams.html

• Sub-micron aerosol is collected, WSOC concentration is measured in near-real time
  http://www.brechtel.com/chemistry.html

• Sub-micron aerosol is collected in vials
• Post-processing laboratory analysis by IC yields concentrations of common anions (Br-, Cl-, NO^2-, NO^3-, SO4^2-, oxalate) and cations (NH⁴⁺, Na⁺, Ca²⁺, Mg²⁺, K⁺)
• More complex analytical techniques are possible with stored aqueous samples
  http://www.brechtel.com/chemistry.html

• Provides real-time measurement of sulfate aerosol after quantitative conversion to SO2
  http://www.thermoscientific.com/ecomm/servlet/productsdetail_11152___11962248_-1

• Measures black carbon (BC) mass concentrations for single particles based on laser-induced incandescence
• Sensitive to 90-500nm BC particles
• Provides a measure of coating thickness (assuming a core-shell model) by simultaneously assessing scattering intensity spectra
  http://dropletmeasurement.com/products/ground-based/sp2.html

• Measures polycyclic aromatic hydrocarbon (PAH) concentrations by measuring the charge produced by UV ionization
  http://www.ecochem.biz/PAH/PAS2000.htm

• Provides concentrations of organic carbon (OC) and elemental carbon (EC) on collected filters
  http://www.sunlab.com/products-services/lab-aerosol-analyzer.html

• Single-particle measurement of the optical size, asymmetry factor, and fluorescence characteristics of biological aerosols (e.g., bacteria, viruses, plant debris, pollens, fungal spores, chlorophyll, etc.)
• Sensitive to particles with optical diameter greater than 500nm
• Operates with two excitation wavelengths (280nm and 370nm) in order to distinguish between different types of biological material and to assess viability
  http://dropletmeasurement.com/products/ground-based/wideband-integrated-bioaerosol-sensor.html