Characteristic nature of vertical motions observed in Arctic mixed-phase stratocumulus
Over the Arctic Ocean, little is known on cloud-generated buoyant overturning vertical motions within mixed-phase stratocumulus clouds. Characteristics of such motions are important for understanding the diabatic processes associated with the vertical motions, the lifetime of the cloud layer and its...
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ftdoajarticles:oai:doaj.org/article:ec912604ee224046a3464803aaa62b67 2023-05-15T14:53:04+02:00 Characteristic nature of vertical motions observed in Arctic mixed-phase stratocumulus J. Sedlar M. D. Shupe 2014-04-01T00:00:00Z https://doi.org/10.5194/acp-14-3461-2014 https://doaj.org/article/ec912604ee224046a3464803aaa62b67 EN eng Copernicus Publications http://www.atmos-chem-phys.net/14/3461/2014/acp-14-3461-2014.pdf https://doaj.org/toc/1680-7316 https://doaj.org/toc/1680-7324 1680-7316 1680-7324 doi:10.5194/acp-14-3461-2014 https://doaj.org/article/ec912604ee224046a3464803aaa62b67 Atmospheric Chemistry and Physics, Vol 14, Iss 7, Pp 3461-3478 (2014) Physics QC1-999 Chemistry QD1-999 article 2014 ftdoajarticles https://doi.org/10.5194/acp-14-3461-2014 2022-12-31T01:18:17Z Over the Arctic Ocean, little is known on cloud-generated buoyant overturning vertical motions within mixed-phase stratocumulus clouds. Characteristics of such motions are important for understanding the diabatic processes associated with the vertical motions, the lifetime of the cloud layer and its micro- and macrophysical characteristics. In this study, we exploit a suite of surface-based remote sensors over the high-Arctic sea ice during a weeklong period of persistent stratocumulus in August 2008 to derive the in-cloud vertical motion characteristics. In-cloud vertical velocity skewness and variance profiles are found to be strikingly different from observations within lower-latitude stratocumulus, suggesting these Arctic mixed-phase clouds interact differently with the atmospheric thermodynamics (cloud tops extending above a stable temperature inversion base) and with a different coupling state between surface and cloud. We find evidence of cloud-generated vertical mixing below cloud base, regardless of surface–cloud coupling state, although a decoupled surface–cloud state occurred most frequently. Detailed case studies are examined, focusing on three levels within the cloud layer, where wavelet and power spectral analyses are applied to characterize the dominant temporal and horizontal scales associated with cloud-generated vertical motions. In general, we find a positively correlated vertical motion signal amongst vertical levels within the cloud and across the full cloud layer depth. The coherency is dependent upon other non-cloud controlled factors, such as larger, mesoscale weather passages and radiative shielding of low-level stratocumulus by one or more cloud layers above. Despite the coherency in vertical velocity across the cloud, the velocity variances were always weaker near cloud top, relative to cloud middle and base. Taken in combination with the skewness, variance and thermodynamic profile characteristics, we observe vertical motions near cloud top that behave differently than those from ... Article in Journal/Newspaper Arctic Arctic Ocean Sea ice Directory of Open Access Journals: DOAJ Articles Arctic Arctic Ocean Atmospheric Chemistry and Physics 14 7 3461 3478 |
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Directory of Open Access Journals: DOAJ Articles |
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English |
topic |
Physics QC1-999 Chemistry QD1-999 |
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Physics QC1-999 Chemistry QD1-999 J. Sedlar M. D. Shupe Characteristic nature of vertical motions observed in Arctic mixed-phase stratocumulus |
topic_facet |
Physics QC1-999 Chemistry QD1-999 |
description |
Over the Arctic Ocean, little is known on cloud-generated buoyant overturning vertical motions within mixed-phase stratocumulus clouds. Characteristics of such motions are important for understanding the diabatic processes associated with the vertical motions, the lifetime of the cloud layer and its micro- and macrophysical characteristics. In this study, we exploit a suite of surface-based remote sensors over the high-Arctic sea ice during a weeklong period of persistent stratocumulus in August 2008 to derive the in-cloud vertical motion characteristics. In-cloud vertical velocity skewness and variance profiles are found to be strikingly different from observations within lower-latitude stratocumulus, suggesting these Arctic mixed-phase clouds interact differently with the atmospheric thermodynamics (cloud tops extending above a stable temperature inversion base) and with a different coupling state between surface and cloud. We find evidence of cloud-generated vertical mixing below cloud base, regardless of surface–cloud coupling state, although a decoupled surface–cloud state occurred most frequently. Detailed case studies are examined, focusing on three levels within the cloud layer, where wavelet and power spectral analyses are applied to characterize the dominant temporal and horizontal scales associated with cloud-generated vertical motions. In general, we find a positively correlated vertical motion signal amongst vertical levels within the cloud and across the full cloud layer depth. The coherency is dependent upon other non-cloud controlled factors, such as larger, mesoscale weather passages and radiative shielding of low-level stratocumulus by one or more cloud layers above. Despite the coherency in vertical velocity across the cloud, the velocity variances were always weaker near cloud top, relative to cloud middle and base. Taken in combination with the skewness, variance and thermodynamic profile characteristics, we observe vertical motions near cloud top that behave differently than those from ... |
format |
Article in Journal/Newspaper |
author |
J. Sedlar M. D. Shupe |
author_facet |
J. Sedlar M. D. Shupe |
author_sort |
J. Sedlar |
title |
Characteristic nature of vertical motions observed in Arctic mixed-phase stratocumulus |
title_short |
Characteristic nature of vertical motions observed in Arctic mixed-phase stratocumulus |
title_full |
Characteristic nature of vertical motions observed in Arctic mixed-phase stratocumulus |
title_fullStr |
Characteristic nature of vertical motions observed in Arctic mixed-phase stratocumulus |
title_full_unstemmed |
Characteristic nature of vertical motions observed in Arctic mixed-phase stratocumulus |
title_sort |
characteristic nature of vertical motions observed in arctic mixed-phase stratocumulus |
publisher |
Copernicus Publications |
publishDate |
2014 |
url |
https://doi.org/10.5194/acp-14-3461-2014 https://doaj.org/article/ec912604ee224046a3464803aaa62b67 |
geographic |
Arctic Arctic Ocean |
geographic_facet |
Arctic Arctic Ocean |
genre |
Arctic Arctic Ocean Sea ice |
genre_facet |
Arctic Arctic Ocean Sea ice |
op_source |
Atmospheric Chemistry and Physics, Vol 14, Iss 7, Pp 3461-3478 (2014) |
op_relation |
http://www.atmos-chem-phys.net/14/3461/2014/acp-14-3461-2014.pdf https://doaj.org/toc/1680-7316 https://doaj.org/toc/1680-7324 1680-7316 1680-7324 doi:10.5194/acp-14-3461-2014 https://doaj.org/article/ec912604ee224046a3464803aaa62b67 |
op_doi |
https://doi.org/10.5194/acp-14-3461-2014 |
container_title |
Atmospheric Chemistry and Physics |
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14 |
container_issue |
7 |
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3461 |
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3478 |
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