In-situ observations of cloud microphysics over Arabian Sea during dust transport events
(2024) In Environmental Research Communications 6(5).- Abstract
The unique in situ measurements of clouds and precipitation within the shallow and deep cumulus over the north-eastern Arabian Sea region during the Indian monsoon are illustrated in this study with a focus on droplet spectral parameters. The observational period showed a significant incursion of Arabian dust and the presence of giant cloud condensation nuclei (GCCN), modifying the cloud and precipitation spectral properties. Warm rain microphysics supported the mixed-phase development in these clouds and exhibited hydrometeors of snow, graupel and large aggregates as part of ice processes. Cloud base droplet number concentration is about 142 ± 79 cm−3 which is one third of the cloud condensation nuclei (CCN) number... (More)
The unique in situ measurements of clouds and precipitation within the shallow and deep cumulus over the north-eastern Arabian Sea region during the Indian monsoon are illustrated in this study with a focus on droplet spectral parameters. The observational period showed a significant incursion of Arabian dust and the presence of giant cloud condensation nuclei (GCCN), modifying the cloud and precipitation spectral properties. Warm rain microphysics supported the mixed-phase development in these clouds and exhibited hydrometeors of snow, graupel and large aggregates as part of ice processes. Cloud base droplet number concentration is about 142 ± 79 cm−3 which is one third of the cloud condensation nuclei (CCN) number concentration at 0.2% supersaturation. A rapid broadening of droplet size distribution (DSD) near to the cloud base was noted in contrast to polluted continental clouds. Relationship between the relative dispersion ( ϵ ; the ratio of DSD spectral width ( σ ) to mean radius ( r m )) and liquid water adiabatic fraction (AF) indicates that the entrainment effect has increased relative dispersion significantly (2-3 times larger) in these clouds. Effective radius ( r eff ) is found to be proportional to mean volume radius ( r v ) with a proportionality constant ( β ) that varies between 1.0-1.6, depending on the spectral dispersion parameter. Drop size distributions for the small cloud droplets with size range 2-50 μ m and the large drizzle drops (or ice hydrometeors) with size range 100-6400 μ m are parameterized using the gamma function distributions useful for large-scale cloud models.
(Less)
- author
- Bera, Sudarsan ; Patade, Sachin LU and Prabhakaran, Thara
- organization
- publishing date
- 2024-05-01
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Arabian Sea, cloud microphysics, dust, In-situ, observations
- in
- Environmental Research Communications
- volume
- 6
- issue
- 5
- article number
- 055009
- publisher
- IOP Publishing
- external identifiers
-
- scopus:85193214158
- ISSN
- 2515-7620
- DOI
- 10.1088/2515-7620/ad443d
- language
- English
- LU publication?
- yes
- id
- ab45eb6b-6121-4edf-aad5-4a2eff7ff559
- date added to LUP
- 2024-06-03 09:25:26
- date last changed
- 2024-06-03 09:26:07
@article{ab45eb6b-6121-4edf-aad5-4a2eff7ff559,
abstract = {{<p>The unique in situ measurements of clouds and precipitation within the shallow and deep cumulus over the north-eastern Arabian Sea region during the Indian monsoon are illustrated in this study with a focus on droplet spectral parameters. The observational period showed a significant incursion of Arabian dust and the presence of giant cloud condensation nuclei (GCCN), modifying the cloud and precipitation spectral properties. Warm rain microphysics supported the mixed-phase development in these clouds and exhibited hydrometeors of snow, graupel and large aggregates as part of ice processes. Cloud base droplet number concentration is about 142 ± 79 cm<sup>−3</sup> which is one third of the cloud condensation nuclei (CCN) number concentration at 0.2% supersaturation. A rapid broadening of droplet size distribution (DSD) near to the cloud base was noted in contrast to polluted continental clouds. Relationship between the relative dispersion ( ϵ ; the ratio of DSD spectral width ( σ ) to mean radius ( r m )) and liquid water adiabatic fraction (AF) indicates that the entrainment effect has increased relative dispersion significantly (2-3 times larger) in these clouds. Effective radius ( r eff ) is found to be proportional to mean volume radius ( r v ) with a proportionality constant ( β ) that varies between 1.0-1.6, depending on the spectral dispersion parameter. Drop size distributions for the small cloud droplets with size range 2-50 μ m and the large drizzle drops (or ice hydrometeors) with size range 100-6400 μ m are parameterized using the gamma function distributions useful for large-scale cloud models.</p>}},
author = {{Bera, Sudarsan and Patade, Sachin and Prabhakaran, Thara}},
issn = {{2515-7620}},
keywords = {{Arabian Sea; cloud microphysics; dust; In-situ; observations}},
language = {{eng}},
month = {{05}},
number = {{5}},
publisher = {{IOP Publishing}},
series = {{Environmental Research Communications}},
title = {{In-situ observations of cloud microphysics over Arabian Sea during dust transport events}},
url = {{http://dx.doi.org/10.1088/2515-7620/ad443d}},
doi = {{10.1088/2515-7620/ad443d}},
volume = {{6}},
year = {{2024}},
}