Evolution of mixing state of black carbon particles: Aircraft measurements over the western Pacific in March 2004

We report the evolution of the mixing state of black carbon (BC) particles in urban plumes measured by an airborne single particle soot photometer. The aircraft observations were conducted over the ocean near the coast of Japan in March 2004. The number fraction of coated BC particles with a core diameter of 180 nm increased from 0.35 to 0.63 within 12 hours (h), namely 2.3% h−1, after being emitted from the Nagoya urban area in Japan. BC particles with a core diameter of 250 nm increased at the slower rate of 1.0% h−1. The increase in coated BC particles was associated with increases in non‐sea salt sulfate and water‐soluble organic carbon by a factor of approximately two, indicating that these compounds contributed to the coating on the BC particles. These results give direct evidence that BC particles become internally mixed on a time scale of 12 h in urban plumes.

[1]  J. Abatzoglou,et al.  Wave breaking along the stratospheric polar vortex as seen in ERA‐40 data , 2007 .

[2]  Yutaka Kondo,et al.  Effects of Mixing State on Black Carbon Measurements by Laser-Induced Incandescence , 2007 .

[3]  Yutaka Kondo,et al.  Time‐resolved measurements of water‐soluble organic carbon in Tokyo , 2006 .

[4]  T. Bond,et al.  Limitations in the enhancement of visible light absorption due to mixing state , 2006 .

[5]  Axel Lauer,et al.  Single‐particle measurements of midlatitude black carbon and light‐scattering aerosols from the boundary layer to the lower stratosphere , 2006 .

[6]  N. Takegawa,et al.  Temporal variations of elemental carbon in Tokyo , 2006 .

[7]  M. Molina,et al.  Processing of soot in an urban environment: case study from the Mexico City Metropolitan Area , 2005 .

[8]  James Allan,et al.  Characterization of an Aerodyne Aerosol Mass Spectrometer (AMS): Intercomparison with Other Aerosol Instruments , 2005 .

[9]  Tami C. Bond,et al.  Export efficiency of black carbon aerosol in continental outflow: Global implications , 2005 .

[10]  G. Carmichael,et al.  Removal of NOx and NOy in Asian outflow plumes: Aircraft measurements over the western Pacific in January 2002 , 2004 .

[11]  Y. Kondo,et al.  Intercontinental Transport and Chemical Transformation 2002 (ITCT 2K2) and Pacific Exploration of Asian Continental Emission (PEACE) experiments: An overview of the 2002 winter and spring intensives , 2004 .

[12]  Barry J. Huebert,et al.  Size distributions and mixtures of dust and black carbon aerosol in Asian outflow: Physiochemistry and optical properties , 2004 .

[13]  Jay R. Turner,et al.  A method for on‐line measurement of water‐soluble organic carbon in ambient aerosol particles: Results from an urban site , 2004 .

[14]  P. Mcmurry,et al.  Measurement of Inherent Material Density of Nanoparticle Agglomerates , 2004 .

[15]  G. Raga,et al.  Warming of the Arctic lower stratosphere by light absorbing particles , 2004 .

[16]  D. Blake,et al.  Highlights of OH, H2SO4, and methane sulfonic acid measurements made aboard the NASA P‐3B during Transport and Chemical Evolution over the Pacific , 2003 .

[17]  D. Blake,et al.  Description of the analysis of a wide range of volatile organic compounds in whole air samples collected during PEM-tropics A and B. , 2001, Analytical chemistry.

[18]  Rodney J. Weber,et al.  A Particle-into-Liquid Collector for Rapid Measurement of Aerosol Bulk Chemical Composition , 2001 .

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

[20]  J. Seinfeld,et al.  Atmospheric Chemistry and Physics: From Air Pollution to Climate Change , 1998 .

[21]  K. Coakley,et al.  Novel method to classify aerosol particles according to their mass-to-charge ratio—Aerosol particle mass analyser , 1996 .

[22]  F. Raes Entrainment of free tropospheric aerosols as a regulating mechanism for cloud condensation nuclei in the remote marine boundary layer , 1995 .