Articles | Volume 24, issue 1
https://doi.org/10.5194/acp-24-109-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-24-109-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| Highlight paper
| 
05 Jan 2024
Research article | Highlight paper |
| 05 Jan 2024
| 05 Jan 2024
Climatologically invariant scale invariance seen in distributions of cloud horizontal sizes
Thomas D. DeWitt
Department of Atmospheric Sciences, University of Utah, 135 S 1460 E, Salt Lake City, UT 84112, USA
Department of Atmospheric Sciences, University of Utah, 135 S 1460 E, Salt Lake City, UT 84112, USA
Karlie N. Rees
Department of Atmospheric Sciences, University of Utah, 135 S 1460 E, Salt Lake City, UT 84112, USA
Corey Bois
Department of Atmospheric Sciences, University of Utah, 135 S 1460 E, Salt Lake City, UT 84112, USA
Steven K. Krueger
Department of Atmospheric Sciences, University of Utah, 135 S 1460 E, Salt Lake City, UT 84112, USA
Nicolas Ferlay
LOA – Laboratoire d'Optique Atmosphérique, UMR 8518, CNRS, University of Lille, 59000 Lille, France
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Kyle E. Fitch, Chaoxun Hang, Ahmad Talaei, and Timothy J. Garrett
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Executive editor
The field of climate prediction has been bedeviled by the problem of how to represent the enormous complexity of clouds. The usual strategy is to peform deterministic simulations with advanced cloud models.
The study outlined here concentrates on a statistical approach that is arguably better suited to determining the mean climatological state.
The presented observations from a wide range of satellite platforms show that a power-law well describes frequencies of occurence of cloud sizes across a very wide range of scales, and that the exponent is robust to local climatological characteristics as surface temperature, aerosol loading, Coriolis forces, or dominant cloud type. Instead, the distribution of cloud sizes emerge simply from a competition for energy and air that occurs due to small-scale cloud mixing processes at cloud edge.
The field of climate prediction has been bedeviled by the problem of how to represent the...
Short summary
Viewed from space, a defining feature of Earth's atmosphere is the wide spectrum of cloud sizes. A recent study predicted the distribution of cloud sizes, and this paper compares the prediction to observations. Although there is nuance in viewing perspective, we find robust agreement with theory across different climatological conditions, including land–ocean contrasts, time of year, or latitude, suggesting a minor role for Coriolis forces, aerosol loading, or surface temperature.
Viewed from space, a defining feature of Earth's atmosphere is the wide spectrum of cloud sizes....
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