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Recent Experiments with the Particle-Into-Liquid Sampler. Rodney Weber, Yilin Ma, Amy Sullivan, K. Maxwell-Meier Doug Orsini, Chul Song - Georgia Tech - Outline PILS description. One instrument (PILS-IC), many compounds Highlights from aircraft studies
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Recent Experiments with the Particle-Into-Liquid Sampler Rodney Weber, Yilin Ma, Amy Sullivan, K. Maxwell-Meier Doug Orsini, Chul Song - Georgia Tech - Outline • PILS description. • One instrument (PILS-IC), many compounds • Highlights from aircraft studies • Yosemite National Park (Jeff Collett et al.). • Recent results measuring water-soluble OC
Particle-Into-Liquid-Sampler Schematic A method to continuously collect particles into a flowing liquid Vac. Pump Transport Liq. Flow Sample Air Flow: 10 to 20 L/min Steam Generator Drains Sample Water Continuous liquid flow at selectable rate; 30 nl/min to 2 ml/min. Concentrated liquid sample. Fast response time.
PILS-IC Measurements from Aircraft TRACE-P and ACE-ASIA March 30 - May 6, 2001 Feb. 24 - April 10, 2001 C 130 viewed from P3
TRACE-P and ACE-Asia ACE TRACE TRACE-P: Feb. 24 - April 10, 2001 ACE-Asia: March 30 - May 6, 2001
Comparisons: Airborne Measurements of Fine Particles- Unique insights from rapid measurements - time • Consistently lower concentrations on P3-B • C-130: Low Turbulence Inlet • P3-B: Standard Diffuser Inlet Ma et al., JGR, 2003
Major Sources of Inorganic Particles Compounds can interact when plumes are mixed KNO3, K2SO4 (NH4)2SO4, NH4NO3 CaCO3, MgCO3 NaCl
TRACE-P: Biomass Burning in Southeast Asia (Thailand) AVHRR Fire Counts For 3/7/01 Modeled BC emissions F10: 3/9/01 From Carmichael, U. Iowa, and Fuelberg, FSU
Characteristics of the Biomass Plume:Aircraft Soundings Pass A Pass B Biomass plume Urban/ Indust. • K+ - light absorbing particles, r2 = 0.73 • K+ - NO3-, r2 = 0.64 • K+ - NH4+, r2 = 0.47 • K+ - CO, r2 = 0.61 • No correlation with Na+ (0.03) and Ca2+ (0.01)(sea salt and dust) All TRACE-P & ACE-Asia Data: • Fine particulate K+ mainly in BB plume, (marker). Ma et al. JGR 2003
TRACE-P Latitude > 25°N Fine Particulate Potassium Spatial Distribution and Relation to PM(fine) “Mass” TRACE-P K+ concentrations K+ dK+/dSO42- High in biomass, low in fossil fuel plumes • K+ found throughout TRACE-P experiment (and ACE-Asia) • Most polluted plumes had highest fractions of K+/SO42- • Biomass/biofuel burning a significant component of spring time Asian emissions
http://daac.gsfc.nasa.gov/CAMPAIGN_DOCS/OCDST/asian_dust.htmlhttp://daac.gsfc.nasa.gov/CAMPAIGN_DOCS/OCDST/asian_dust.html A Large Dust Event During ACE Asia SeaWiFS April 7/01
Reactions Between Acidic Gases and Fine Mineral Dust An accommodation coefficient dependence on RH? CaCO3 + 2HNO3 Ca(NO3)2 + H2O + CO2 CaCO3 + H2SO4 CaSO4 + H2O + CO2 CaCO3 + SO2 . . . CaSO4 + … Fraction of Carbonate Replaced Inferred from Ion balance (cations-anions) Maxwell-Meier et al. 2004
Measurements of a Suite of Compounds Is Useful Even in the US On the speciation and measurement of aerosol nitrate in regional aerosols J. L. Collett, T. Lee, X. Yu, and S. M. Kreidenweis Colorado State University W. J. Malm – National Park Service Funding: National Park Service
Similar results in Tokyo - Kondo et al. (PM2.5) NO3- Na+ Cl-
Studies of PM2.5 Water-Soluble Organic CarbonBroad Classification of Organic Compounds 6-minute measurement LOD 0.1 µgC/m3 WSOC is operationally defined as the fraction of OC in water at 0.01 to 0.025 gC/100L that passes through a 0.45 µm filter.
St Louis Midwest SupersiteAmy Sullivan, Andrea Clements, Jay Turner, Minsuk Bae, and James Schauer • Mean WSOC/OC: June,August, Oct.: 0.64,0.61, 0.31 • At times WSOC may be composed of more aged (oxidized) compounds. • “Fresh” plumes are mainly water-insoluble OC. • Need to chemically sub-divide the WSOC fraction of OC on-line.
Summary: Pros of Liquid Systems Many compounds detected with single instrument (i.e., ion chromatography) Anions: Cl-, NO2-, NO3-, SO42-, organic acids etc. Cations: Na+, NH4+, K+, Mg2+, Ca2+, (many situations where more than NH4+ important) Generally less susceptible to artifacts than integrated filters. Capable of measuring total (coarse + fine) or fine particles. “Easy” analysis, straight-forward calibrations, quantitative (ion balance). High sensitivity, order of ng/m3 (IC measurement) Amenable to a range of detectors
Summary: Cons of Liquid Systems • No (or at least very limited) size resolving capabilities. • Must deal with liquids, more complex less robust instrument. • Must have a clean source of water. • Possible interferences under unique conditions • Houston TEXAQS, PILS-IC: not K+, likely an ethanolamine. • May have there own set of artifacts.