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05:07
Assessing the Particulate Matter Removal Abilities of Tree Leaves
Published on: October 7, 2018
Reduction of tropical cloudiness by soot
1NASA Ames Research Center, Moffett Field, CA 94035, USA. University of Colorado, Boulder, CO 80309, USA. Lawrence Livermore National Laboratory, Livermore, CA 94551, USA. National Center for Atmospheric Research, Boulder, CO 80301, USA.
Science (New York, N.Y.)
|May 12, 2000
Summary
Enhanced aerosol concentrations typically cool the climate. However, this study reveals aerosols can paradoxically reduce cloud cover, offsetting cooling effects regionally.
Area of Science:
- Atmospheric Science
- Climate Science
- Cloud Physics
Background:
- Aerosol pollution is conventionally understood to cool the global climate.
- This cooling occurs via increased cloud albedo, droplet size, and water content.
Purpose of the Study:
- To investigate an alternative mechanism where aerosols reduce cloud cover.
- To demonstrate how this can offset regional aerosol-induced radiative cooling.
Main Methods:
- Utilizing model simulations to analyze aerosol-cloud interactions.
- Focusing on daytime clearing of trade cumulus clouds.
Main Results:
- Aerosols can accelerate and intensify the daytime clearing of trade cumulus clouds.
- Solar heating of dark haze exacerbates this cloud reduction effect.
Conclusions:
- Aerosols can exert a regional warming influence by decreasing cloud cover.
- This counteracts the expected net cooling effect of aerosol pollution.
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