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Fragmentation in Collisions of Snow with Graupel/Hail : New Formulation from Field Observations

Gautam, Martanda LU ; Waman, Deepak LU orcid ; Patade, Sachin LU ; Deshmukh, Akash LU ; Phillips, Vaughan LU orcid ; Jackowicz-Korczynski, Marcin LU ; Pazhambilly Paul, Freddy LU ; Smith, Paul and Bansemer, Aaron (2024) In Journal of the Atmospheric Sciences 81(12). p.2149-2164
Abstract

Secondary ice production (SIP) has been attributed to the generation of most ice particles observed in precipitating clouds with cloud tops warmer than 2368C, from various aircraft- and ground-based field observations across the globe. One of the known SIP mechanisms is fragmentation during collisions among ice particles. It has been studied with our theoretical formulation, which has been applied in microphysical schemes of atmospheric models in a few studies. These have predicted an extensive impact on cloud glaciation and radiative properties. However, there has been a lack of experimental field studies, especially involving naturally falling snowflakes, to better understand this particular mechanism of SIP. This study reports the... (More)

Secondary ice production (SIP) has been attributed to the generation of most ice particles observed in precipitating clouds with cloud tops warmer than 2368C, from various aircraft- and ground-based field observations across the globe. One of the known SIP mechanisms is fragmentation during collisions among ice particles. It has been studied with our theoretical formulation, which has been applied in microphysical schemes of atmospheric models in a few studies. These have predicted an extensive impact on cloud glaciation and radiative properties. However, there has been a lack of experimental field studies, especially involving naturally falling snowflakes, to better understand this particular mechanism of SIP. This study reports the first field measurements with modern technology for fragmentation during collisions between naturally falling snowflakes and graupel/hail particles. This was observed with an innovatively designed portable chamber that was deployed outdoors in northern Sweden. Applying the observations from this field-based study, we optimized the existing formulation for predicting numbers of fragments from collisions of snow with graupel/hail. The observations show the average numbers of fragments per collision for dendritic (3–12 mm) and nondendritic (1–3 mm) snow were about 12 and 1, respectively. This represents a boost of predicted fragment numbers relative to our original formulation published in 2017. The updated formulation for breakup in ice–ice collisions can be implemented in the microphysical schemes of atmospheric models.

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author
; ; ; ; ; ; ; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Cloud microphysics, Cloud parameterizations, In situ atmospheric observations, Measurements, Optimization, Secondary ice production
in
Journal of the Atmospheric Sciences
volume
81
issue
12
pages
16 pages
publisher
Amer Meteorological Soc
external identifiers
  • scopus:85213813433
ISSN
0022-4928
DOI
10.1175/JAS-D-23-0122.1
language
English
LU publication?
yes
id
55c83bd8-9cfe-4e68-87ef-7fb3104e9e93
date added to LUP
2025-02-24 15:48:04
date last changed
2025-04-04 13:53:59
@article{55c83bd8-9cfe-4e68-87ef-7fb3104e9e93,
  abstract     = {{<p>Secondary ice production (SIP) has been attributed to the generation of most ice particles observed in precipitating clouds with cloud tops warmer than 2368C, from various aircraft- and ground-based field observations across the globe. One of the known SIP mechanisms is fragmentation during collisions among ice particles. It has been studied with our theoretical formulation, which has been applied in microphysical schemes of atmospheric models in a few studies. These have predicted an extensive impact on cloud glaciation and radiative properties. However, there has been a lack of experimental field studies, especially involving naturally falling snowflakes, to better understand this particular mechanism of SIP. This study reports the first field measurements with modern technology for fragmentation during collisions between naturally falling snowflakes and graupel/hail particles. This was observed with an innovatively designed portable chamber that was deployed outdoors in northern Sweden. Applying the observations from this field-based study, we optimized the existing formulation for predicting numbers of fragments from collisions of snow with graupel/hail. The observations show the average numbers of fragments per collision for dendritic (3–12 mm) and nondendritic (1–3 mm) snow were about 12 and 1, respectively. This represents a boost of predicted fragment numbers relative to our original formulation published in 2017. The updated formulation for breakup in ice–ice collisions can be implemented in the microphysical schemes of atmospheric models.</p>}},
  author       = {{Gautam, Martanda and Waman, Deepak and Patade, Sachin and Deshmukh, Akash and Phillips, Vaughan and Jackowicz-Korczynski, Marcin and Pazhambilly Paul, Freddy and Smith, Paul and Bansemer, Aaron}},
  issn         = {{0022-4928}},
  keywords     = {{Cloud microphysics; Cloud parameterizations; In situ atmospheric observations; Measurements; Optimization; Secondary ice production}},
  language     = {{eng}},
  number       = {{12}},
  pages        = {{2149--2164}},
  publisher    = {{Amer Meteorological Soc}},
  series       = {{Journal of the Atmospheric Sciences}},
  title        = {{Fragmentation in Collisions of Snow with Graupel/Hail : New Formulation from Field Observations}},
  url          = {{http://dx.doi.org/10.1175/JAS-D-23-0122.1}},
  doi          = {{10.1175/JAS-D-23-0122.1}},
  volume       = {{81}},
  year         = {{2024}},
}