Sotiropoulou, G, Vignon, É, Young, G orcid.org/0000-0002-8464-7332 et al. (5 more authors) (2021) Secondary ice production in summer clouds over the Antarctic coast: an underappreciated process in atmospheric models. Atmospheric Chemistry and Physics, 21 (2). pp. 755-771. ISSN 1680-7316
Abstract
The correct representation of Antarctic clouds in atmospheric models is crucial for accurate projections of the future Antarctic climate. This is particularly true for summer clouds which play a critical role in the surface melting of the ice shelves in the vicinity of the Weddell Sea. The pristine atmosphere over the Antarctic coast is characterized by low concentrations of ice nucleating particles (INPs) which often result in the formation of supercooled liquid clouds. However, when ice formation occurs, the ice crystal number concentrations (ICNCs) are substantially higher than those predicted by existing primary ice nucleation parameterizations. The rime-splintering mechanism, thought to be the dominant secondary ice production (SIP) mechanism at temperatures between −8 and −3 ∘C, is also weak in the Weather and Research Forecasting model. Including a parameterization for SIP due to breakup (BR) from collisions between ice particles improves the ICNC representation in the modeled mixed-phase clouds, suggesting that BR could account for the enhanced ICNCs often found in Antarctic clouds. The model results indicate that a minimum concentration of about ∼ 0.1 L−1 of primary ice crystals is necessary and sufficient to initiate significant breakup to explain the observations, while our findings show little sensitivity to increasing INPs. The BR mechanism is currently not represented in most weather prediction and climate models; including this process can have a significant impact on the Antarctic radiation budget.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © Author(s) 2021. This work is distributed under the Creative Commons Attribution 4.0 License. |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Environment (Leeds) > School of Earth and Environment (Leeds) > Inst for Climate & Atmos Science (ICAS) (Leeds) |
Funding Information: | Funder Grant number NERC (Natural Environment Research Council) NE/R009686/1 |
Depositing User: | Symplectic Publications |
Date Deposited: | 26 Jan 2021 13:10 |
Last Modified: | 26 Jan 2021 13:10 |
Status: | Published |
Publisher: | Copernicus Publications |
Identification Number: | 10.5194/acp-21-755-2021 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:170279 |