Design and Application of a Pulsed Cavity Ring-Down Aerosol Extinction Spectrometer for Field Measurements

This paper describes the design and application of a pulsed cavity ring-down aerosol extinction spectrometer (CRD-AES) for in-situ atmospheric measurement of the aerosol extinction coefficient and its relative humidity dependence. This CRD-AES measures the aerosol extinction coefficient (σ ep) at 355 nm, 532 nm, 683 nm, and 1064 nm with a minimal size dependent bias for particles with diameter less than 10 μm. The σ ep at 532 nm is measured with an accuracy of 1% when extinction is ≥ 10 Mm −1 . The precision is limited by statistical fluctuations within the small optical volume and the time resolution of extinction at 2% uncertainty for various air mass types is evaluated. The CRD-AES is configured with two separate cavity ring-down cells for measurement of the extinction coefficient at 532 nm. This allows the determination of the RH dependence of extinction at 532 nm through independent RH control of the sample for each measurement. Gas phase absorption and minimization of potential interferences is also considered.

[1]  J. Ogren,et al.  Determining Aerosol Radiative Properties Using the TSI 3563 Integrating Nephelometer , 1998 .

[2]  Anthony W. Strawa,et al.  The Measurement of Aerosol Optical Properties Using Continuous Wave Cavity Ring-Down Techniques , 2003 .

[3]  Israel Schechter,et al.  Aerosol analysis by cavity-ring-down laser spectroscopy , 2002 .

[4]  Stephen E. Schwartz,et al.  Uncertainty Requirements in Radiative Forcing of Climate Change , 2004, Journal of the Air & Waste Management Association.

[5]  A. R. Ravishankara,et al.  Measurement of aerosol optical extinction at 532 nm with pulsed cavity ring down spectroscopy , 2004 .

[6]  A. O’Keefe,et al.  Cavity ring‐down optical spectrometer for absorption measurements using pulsed laser sources , 1988 .

[7]  W. Patrick Arnott,et al.  Evaluation of Multiangle Absorption Photometry for Measuring Aerosol Light Absorption , 2005 .

[8]  P. Hobbs,et al.  Optical extinction properties of smoke from the Kuwait oil fires , 1992 .

[9]  W. Patrick Arnott,et al.  Nitrogen dioxide and kerosene-flame soot calibration of photoacoustic instruments for measurement of light absorption by aerosols , 2000 .

[10]  J. Driscoll,et al.  Rayleigh scattering cross sections of combustion species at 266, 355, and 532 nm for thermometry applications. , 2004, Optics letters.

[11]  W. Patrick Arnott,et al.  Cavity Ring-Down and Cavity-Enhanced Detection Techniques for the Measurement of Aerosol Extinction , 2005 .

[12]  Owen B. Toon,et al.  The optical constants of several atmospheric aerosol species: Ammonium sulfate, aluminum oxide, and sodium chloride , 1976 .

[13]  Bruce A. Wielicki,et al.  Scientific Objectives, Measurement Needs, and Challenges Motivating the PARAGON Aerosol Initiative , 2004 .

[14]  Steven S Brown,et al.  Absorption spectroscopy in high-finesse cavities for atmospheric studies. , 2003, Chemical reviews.

[15]  Kenneth W. Busch,et al.  Cavity-ringdown spectroscopy : an ultratrace-absorption measurement technique , 1999 .

[16]  A. Ravishankara,et al.  Measurement of atmospheric NO2 by pulsed cavity ring-down spectroscopy , 2006 .

[17]  R. Jones,et al.  Temperature dependent ultraviolet‐visible absorption cross sections of N2O and N2O4: Low‐temperature measurements of the equilibrium constant for 2NO2 ⇌ N2O4 , 1994 .

[18]  R. Penndorf,et al.  Tables of the Refractive Index for Standard Air and the Rayleigh Scattering Coefficient for the Spectral Region between 0.2 and 20.0 μ and Their Application to Atmospheric Optics , 1957 .

[19]  J. Penner,et al.  Quantifying and minimizing uncertainty of climate forcing by anthropogenic aerosols , 1994 .

[20]  Reinhard F. Bruch,et al.  Photoacoustic spectrometer for measuring light absorption by aerosol: instrument description , 1999 .

[21]  A. Ravishankara,et al.  Parameterization for the relative humidity dependence of light extinction: Organic-ammonium sulfate aerosol , 2007 .

[22]  J. D. de Gouw,et al.  Particle characteristics following cloud-modified transport from Asia to North America , 2004 .

[23]  A. Sullivan,et al.  Variability in ammonium nitrate formation and nitric acid depletion with altitude and location over California , 2003 .

[24]  I. Tang,et al.  Water activities, densities, and refractive indices of aqueous sulfates and sodium nitrate droplets of atmospheric importance , 1994 .

[25]  J. Ogren,et al.  Towards Aerosol Light-Absorption Measurements with a 7-Wavelength Aethalometer: Evaluation with a Photoacoustic Instrument and 3-Wavelength Nephelometer , 2005 .

[26]  J. B. Paul,et al.  Cavity Ringdown Laser Absorption Spectroscopy: History, Development, and Application to Pulsed Molecular Beams. , 1997, Chemical reviews.

[27]  James B. Burkholder,et al.  Temperature dependence of the ozone absorption spectrum over the wavelength range 410 to 760 nm , 1994 .

[28]  P. Barber.  Absorption and scattering of light by small particles , 1984 .

[29]  Larry C. Andrews,et al.  Absorption and Scattering , 2004, Introduction to Optical Microscopy.

[30]  J. Seinfeld,et al.  Studies of concentrated electrolyte solutions using the electrodynamic balance. 1. Water activities for single-electrolyte solutions , 1987 .

[31]  J. Coakley,et al.  Aerosols and Climate , 1974, Science.

[32]  I. Tang.  Chemical and size effects of hygroscopic aerosols on light scattering coefficients , 1996 .

[33]  M. Noguer,et al.  Climate change 2001: The scientific basis. Contribution of Working Group I to the Third Assessment Report of the Intergovernmental Panel on Climate Change , 2002 .

[34]  J. Penner,et al.  Aerosol direct radiative effects over the northwest Atlantic, northwest Pacific, and North Indian Oceans: estimates based on in-situ chemical and optical measurements and chemical transport modeling , 2005 .

[35]  D. Covert,et al.  A Three-Wavelength Optical Extinction Cell for Measuring Aerosol Light Extinction and Its Application to Determining Light Absorption Coefficient , 2005 .

[36]  Tami C. Bond,et al.  Calibration and Intercomparison of Filter-Based Measurements of Visible Light Absorption by Aerosols , 1999 .

[37]  J. Seinfeld,et al.  Studies of concentrated electrolyte solutions using the electrodynamic balance. 3. Solute nucleation , 1987 .

[38]  G. Meijer,et al.  Cavity Ringdown Spectroscopy , 1998, Technical Digest. 1998 EQEC. European Quantum Electronics Conference (Cat. No.98TH8326).

[39]  H. Saatho,et al.  The AIDA soot aerosol characterisation campaign 1999 , 2003 .

[40]  I. Tang.  Deliquescence properties and particle size change of hygroscopic aerosols , 1979 .

[41]  Bruce Morley,et al.  Aerosol hygroscopic properties as measured by lidar and comparison with in situ measurements , 2003 .

[42]  A. R. Ravishankara,et al.  Aerosol Absorption Measurement using Photoacoustic Spectroscopy: Sensitivity, Calibration, and Uncertainty Developments , 2006 .

[43]  Harald Saathoff,et al.  The AIDA soot aerosol characterisation campaign 1999 , 2003 .

[44]  T. Eck,et al.  Comparisons of techniques for measuring shortwave absorption and black carbon content of aerosols from biomass burning in Brazil , 1998 .

[45]  P. Quinn,et al.  Modification, Calibration and a Field Test of an Instrument for Measuring Light Absorption by Particles , 2005 .

[46]  A. R. Ravishankara,et al.  Key factors influencing the relative humidity dependence of aerosol light scattering , 2006 .

[47]  I D Nikolov,et al.  Optical plastic refractive measurements in the visible and the near-infrared regions. , 2000, Applied optics.

[48]  J. Spann,et al.  Measurement of the water cycle in a levitated ammonium sulfate particle , 1984 .

[49]  M. Schnaiter,et al.  Absorption of light by soot particles: determination of the absorption coefficient by means of aethalometers , 2003 .

[50]  Mark J. Rood,et al.  Mixtures of pollution, dust, sea salt, and volcanic aerosol during ACE‐Asia: Radiative properties as a function of relative humidity , 2003 .

[51]  Beat Schmid,et al.  Comparison of Aerosol Single Scattering Albedos Derived by Diverse Techniques in Two North Atlantic Experiments , 2002 .

[52]  Ernest Weingartner,et al.  Effect of humidity on aerosol light absorption and its implications for extinction and the single scattering albedo illustrated for a site in the lower free troposphere , 2005 .

[53]  D. Atkinson.  Solving chemical problems of environmental importance using cavity ring-down spectroscopy. , 2003, The Analyst.

[54]  J. Smith,et al.  A portable pulsed cavity ring-down transmissometer for measurement of the optical extinction of the atmospheric aerosol. , 2001, The Analyst.