| DOI: | 10.1016/j.atmosres.2018.02.013
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| Scopus记录号: | 2-s2.0-85042269428
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| 论文题名: | The effect of ice nuclei on a deep convective cloud in South China |
| 作者: | Deng X.; Xue H.; Meng Z.
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| 刊名: | Atmospheric Research
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| ISSN: | 1698095
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| 出版年: | 2018
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| 卷: | 206 | | 起始页码: | 1
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| 结束页码: | 12
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| 语种: | 英语
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| 英文关键词: | Deep convective cloud
; Heterogeneous nucleation
; Homogeneous freezing
; Ice nucleation
; Ice nuclei
; Vertical transport
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| Scopus关键词: | Aerosols
; Atmospheric thermodynamics
; Clouds
; Drops
; Freezing
; Light polarization
; Mixing
; Nucleation
; Snow
; Spatial distribution
; Weather forecasting
; Deep convective clouds
; Heterogeneous nucleation
; Ice nucleation
; Ice nuclei
; Vertical transports
; Ice
; aerosol
; cloud condensation nucleus
; computer simulation
; concentration (composition)
; convective cloud
; haze
; heterogeneity
; ice
; mixing ratio
; nucleation
; numerical model
; spatial distribution
; updraft
; China
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| 英文摘要: | This study uses the Weather Research and Forecasting Model to simulate a deep convective cloud under a relatively polluted condition in South China. Ice nuclei (IN) aerosols near the surface are effectively transported upwards to above the 0 °C level by the strong updrafts in the convective cloud. Four cases with initial surface IN aerosol concentrations of 1, 10, 100, and 1000 L−1 are simulated. All simulations can well reproduce the major characteristics of the deep convective cloud in terms of the evolution, spatial distribution, and its track. IN aerosols have little effect on these macrophysical characteristics but can significantly affect ice formation. When IN concentration is increased, all heterogeneous nucleation modes are significantly enhanced, whereas the homogeneous freezing of cloud droplets is unchanged or weakened depending on the IN concentration and the development stages of the deep convective cloud. The homogeneous freezing of haze particles is generally not affected by increased IN but is slightly weakened in the extremely high IN case. As IN concentration is increased by 10 and 100 times, the enhanced heterogeneous nucleation is still not strong enough to compete with homogeneous freezing. Ice formation is hence still dominated by the homogenous freezing of cloud droplets and haze particles in the layer of 9–14 km, where most of the ice crystals are produced. The microphysical properties are generally unaffected in all the stages of cloud evolution. As IN concentration is increased by 1000 times and heterogeneous nucleation is further enhanced, the homogeneous freezing of cloud droplets and haze particles dominates only in the mature and dissipating stages, leading to unaffected ice number mixing ratio in the anvil region (approximately above 9 km) for these two stages. However, in the developing stage, when the supply of cloud droplets is limited, the homogeneous freezing of cloud droplets is weakened or even suppressed due to the very strong competition for liquid water with heterogeneous nucleation, leading to significantly lower ice number mixing ratio in the anvil regions. In addition, the microphysical properties in the convective core regions below the cloud anvil (approximately below 9 km) are also affected in the case of 1000 L−1. The enhanced heterogeneous nucleation produces more ice crystals below 9 km, leading to a stronger conversion from ice crystals to snow particles, and hence higher number and mass mixing ratios of snow. The IN effect on the spatial distributions and temporal evolutions of the surface precipitation and updraft velocity is generally insignificant. © 2018 The Authors |
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| 资源类型: | 期刊论文
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| 标识符: | http://119.78.100.158/handle/2HF3EXSE/108909
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| Appears in Collections: | 影响、适应和脆弱性
气候变化事实与影响
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作者单位: | Department of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing, China
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| Recommended Citation: | |
Deng X.,Xue H.,Meng Z.. The effect of ice nuclei on a deep convective cloud in South China[J]. Atmospheric Research,2018-01-01,206
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