Abstract
Aerosol particles from megacities influence the regional and global climate as well as the health of their occupants. We used transmission electron microscopes (TEMs) to study aerosol particles collected from the Los Angeles area during the 2010 CalNex campaign. We detected major amounts of ns-soot, defined as consisting of carbon nanospheres, sulfate, sea salt, and organic aerosol (OA) and lesser amounts of brochosome particles from leaf hoppers. Ns-soot-particle shapes, mixing states, and abundances varied significantly with sampling times and days. Within plumes having high CO2 concentrations, much ns-soot was compacted and contained a relatively large number of carbon nanospheres. Ns-soot particles from both CalNex samples and Mexico City, the latter collected in 2006, had a wide range of shapes when mixed with other aerosol particles, but neither sets showed spherical ns-soot nor the core-shell configuration that is commonly used in optical calculations. Our TEM observations and light-absorption calculations ofmodeled particles indicate that, in contrast to ns-soot particles that are embedded within other materials or have the hypothesized core-shell configurations, those attached to other aerosol particles hardly enhance their light absorption. We conclude that the ways in which ns-soot mixes with other particles explain the observations of smaller light amplification by ns-soot coatings thanmodel calculations during the CalNex campaign and presumably in other areas.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 3723-3730 |
| Number of pages | 8 |
| Journal | Journal of Geophysical Research: Atmospheres |
| Volume | 118 |
| Issue number | 9 |
| DOIs | |
| State | Published - Aug 16 2013 |
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ASJC Scopus subject areas
- Atmospheric Science
- Geophysics
- Earth and Planetary Sciences (miscellaneous)
- Space and Planetary Science
Cite this
Changes of ns-soot mixing states and shapes in an urban area during CalNex. / Adachi, Kouji; Buseck, P R.
In: Journal of Geophysical Research: Atmospheres, Vol. 118, No. 9, 16.08.2013, p. 3723-3730.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Changes of ns-soot mixing states and shapes in an urban area during CalNex
AU - Adachi, Kouji
AU - Buseck, P R
PY - 2013/8/16
Y1 - 2013/8/16
N2 - Aerosol particles from megacities influence the regional and global climate as well as the health of their occupants. We used transmission electron microscopes (TEMs) to study aerosol particles collected from the Los Angeles area during the 2010 CalNex campaign. We detected major amounts of ns-soot, defined as consisting of carbon nanospheres, sulfate, sea salt, and organic aerosol (OA) and lesser amounts of brochosome particles from leaf hoppers. Ns-soot-particle shapes, mixing states, and abundances varied significantly with sampling times and days. Within plumes having high CO2 concentrations, much ns-soot was compacted and contained a relatively large number of carbon nanospheres. Ns-soot particles from both CalNex samples and Mexico City, the latter collected in 2006, had a wide range of shapes when mixed with other aerosol particles, but neither sets showed spherical ns-soot nor the core-shell configuration that is commonly used in optical calculations. Our TEM observations and light-absorption calculations ofmodeled particles indicate that, in contrast to ns-soot particles that are embedded within other materials or have the hypothesized core-shell configurations, those attached to other aerosol particles hardly enhance their light absorption. We conclude that the ways in which ns-soot mixes with other particles explain the observations of smaller light amplification by ns-soot coatings thanmodel calculations during the CalNex campaign and presumably in other areas.
AB - Aerosol particles from megacities influence the regional and global climate as well as the health of their occupants. We used transmission electron microscopes (TEMs) to study aerosol particles collected from the Los Angeles area during the 2010 CalNex campaign. We detected major amounts of ns-soot, defined as consisting of carbon nanospheres, sulfate, sea salt, and organic aerosol (OA) and lesser amounts of brochosome particles from leaf hoppers. Ns-soot-particle shapes, mixing states, and abundances varied significantly with sampling times and days. Within plumes having high CO2 concentrations, much ns-soot was compacted and contained a relatively large number of carbon nanospheres. Ns-soot particles from both CalNex samples and Mexico City, the latter collected in 2006, had a wide range of shapes when mixed with other aerosol particles, but neither sets showed spherical ns-soot nor the core-shell configuration that is commonly used in optical calculations. Our TEM observations and light-absorption calculations ofmodeled particles indicate that, in contrast to ns-soot particles that are embedded within other materials or have the hypothesized core-shell configurations, those attached to other aerosol particles hardly enhance their light absorption. We conclude that the ways in which ns-soot mixes with other particles explain the observations of smaller light amplification by ns-soot coatings thanmodel calculations during the CalNex campaign and presumably in other areas.
UR - http://www.scopus.com/inward/record.url?scp=84881095769&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84881095769&partnerID=8YFLogxK
U2 - 10.1002/jgrd.503212013
DO - 10.1002/jgrd.503212013
M3 - Article
AN - SCOPUS:84881095769
VL - 118
SP - 3723
EP - 3730
JO - Journal of Geophysical Research: Atmospheres
JF - Journal of Geophysical Research: Atmospheres
SN - 2169-897X
IS - 9
ER -