Improved parameterization for the size distribution of emitted dust aerosols reduces model underestimation of super coarse dust

Meng, J., Huang, Y., Leung, D. M., Li, L., Adebiyi, A. A., Ryder, C. L. ORCID: https://orcid.org/0000-0002-9892-6113, Mahowald, N. M. and Kok, J. F. (2022) Improved parameterization for the size distribution of emitted dust aerosols reduces model underestimation of super coarse dust. Geophysical Research Letters, 49 (8). e2021GL097287. ISSN 0094-8276 doi: 10.1029/2021GL097287

Abstract/Summary

Aircraft measurement campaigns have revealed that super coarse dust (diameter >10 μm) surprisingly accounts for approximately a quarter of aerosols by mass in the atmosphere. However, most global aerosol models either underestimate or do not include super coarse dust abundance. To address this problem, we use brittle fragmentation theory to develop a parameterization for the emitted dust size distribution that includes emission of super coarse dust. We implement this parameterization in the Community Earth System Model (CESM) and find that it brings the model in good agreement with aircraft measurements of super coarse dust close to dust source regions. However, the CESM still underestimates super coarse dust in dust outflow regions. Thus, we conclude that the model underestimation of super coarse atmospheric dust is in part due to the underestimation of super coarse dust emission and likely in part due to errors in deposition processes.

Item Type	Article
URI	https://reading-clone.eprints-hosting.org/id/eprint/104995
Identification Number/DOI	10.1029/2021GL097287
Refereed	Yes
Divisions	Science > School of Mathematical, Physical and Computational Sciences > Department of Meteorology
Publisher	American Geophysical Union
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