Extensive Soot Compaction by Cloud Processing from Laboratory and Field Observations
Soot particles form during combustion of carbonaceous materials and impact climate and air quality. When freshly emitted, they are typically fractal-like aggregates. After atmospheric aging, they can act as cloud condensation nuclei, and water condensation or evaporation restructure them to more com...
Saved in:
Published in | Scientific reports Vol. 9; no. 1 |
---|---|
Main Authors | , , , , , , , , , , , , , , , , , , , , , , , , |
Format | Journal Article |
Language | English |
Published |
United Kingdom
Nature Publishing Group
14.08.2019
|
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | Soot particles form during combustion of carbonaceous materials and impact climate and air quality. When freshly emitted, they are typically fractal-like aggregates. After atmospheric aging, they can act as cloud condensation nuclei, and water condensation or evaporation restructure them to more compact aggregates, affecting their optical, aerodynamic, and surface properties. Here we survey the morphology of ambient soot particles from various locations and different environmental and aging conditions. We used electron microscopy and show extensive soot compaction after cloud processing. We further performed laboratory experiments to simulate atmospheric cloud processing under controlled conditions. We find that soot particles sampled after evaporating the cloud droplets, are significantly more compact than freshly emitted and interstitial soot, confirming that cloud processing, not just exposure to high humidity, compacts soot. Our findings have implications for how the radiative, surface, and aerodynamic properties, and the fate of soot particles are represented in numerical models. |
---|---|
Bibliography: | National Aeronautics and Space Administration (NASA) USDOE Office of Science (SC), Biological and Environmental Research (BER) Research Council of Norway LA-UR-19-28388; PNNL-SA-143342 National Science Foundation (NSF) SC0006941; 89233218CNA000001; SC0010019; SC0018931; AC05-76RL01830; F265; NNX12AN97H; 80NSSC17K0449; NNX15AI48G; NNX15AI66G; AGS-1110059; AGS 1039742; AGS-1544425; AGS-1455215; AGS-1754244 USDOE Laboratory Directed Research and Development (LDRD) Program |
ISSN: | 2045-2322 2045-2322 |