Stillwell, RA, Neely III, RR orcid.org/0000-0003-4560-4812, Thayer, JP et al. (3 more authors) (2019) Radiative Influence of Horizontally Oriented Ice Crystals over Summit, Greenland. Journal of Geophysical Research: Atmospheres, 124 (22). pp. 12141-12156. ISSN 2169-897X
Abstract
Ice crystals commonly adopt a horizontal orientation under certain aerodynamic and electrodynamic conditions that occur in the atmosphere. While the radiative impact of horizontally oriented ice crystals (HOIC) has been theoretically studied with respect to their impact on shortwave cloud albedo, the longwave impact remains unexplored. This work analyzes the occurrence of HOIC at Summit, Greenland, from July 2015 to June 2017. Using polarization lidar and ancillary atmospheric sensors, ice crystal orientations are identified and used to interpret cloud radiative impact on the surface radiation budget. We find HOIC occur in at least 25.6% of all ice-only column observations. We find that the shortwave impact of HOIC is to increase cloud radiative effect by approximately 22% for a given solar zenith angle. We also find that the longwave impact of HOIC compared to randomly oriented ice crystals are statistically different at the p < 0.01 significance level, increasing the surface radiative effect by approximately 8% for clouds with infrared optical depths < ~1. We suggest that the observed difference between the surface radiative effect for clouds containing randomly oriented ice crystals and HOIC may be due to enhanced scattering, but this hypothesis needs to be further explored with more detailed observations and modeling.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | ©2019. American Geophysical Union. All Rights Reserved. Uploaded in accordance with the publisher's self-archiving policy. |
Keywords: | Horizontally Oriented Ice Crystals; Arctic; Cloud Radiative Effect |
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) > National Centre for Atmos Science (NCAS) (Leeds) |
Funding Information: | Funder Grant number NERC NE/S00906X/1 |
Depositing User: | Symplectic Publications |
Date Deposited: | 05 Dec 2019 12:58 |
Last Modified: | 26 Apr 2020 00:38 |
Status: | Published |
Publisher: | American Geophysical Union |
Identification Number: | 10.1029/2018JD028963 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:154181 |