DOI: 10.1002/2016JD025278
论文题名: Airborne observations of the microphysical structure of two contrasting cirrus clouds
作者: O'Shea S.J. ; Choularton T.W. ; Lloyd G. ; Crosier J. ; Bower K.N. ; Gallagher M. ; Abel S.J. ; Cotton R.J. ; Brown P.R.A. ; Fugal J.P. ; Schlenczek O. ; Borrmann S. ; Pickering J.C.
刊名: Journal of Geophysical Research: Atmospheres
ISSN: 2169897X
出版年: 2016
卷: 121, 期: 22 起始页码: 510
结束页码: 536
语种: 英语
英文关键词: cirrus
; ice nucleation
; microphysics
Scopus关键词: airborne sensing
; artificial neural network
; cirrus
; cloud microphysics
; concentration (composition)
; data set
; experimental study
; heterogeneity
; high temperature
; ice crystal
; nucleation
; observational method
; parameterization
; particle size
; size distribution
英文摘要: We present detailed airborne in situ measurements of cloud microphysics in two midlatitude cirrus clouds, collected as part of the Cirrus Coupled Cloud-Radiation Experiment. A new habit recognition algorithm for sorting cloud particle images using a neural network is introduced. Both flights observed clouds that were related to frontal systems, but one was actively developing while the other dissipated as it was sampled. The two clouds showed distinct differences in particle number, habit, and size. However, a number of common features were observed in the 2-D stereo data set, including a distinct bimodal size distribution within the higher-temperature regions of the clouds. This may result from a combination of local heterogeneous nucleation and large particles sedimenting from aloft. Both clouds had small ice crystals (<100 µm) present at all levels However, this small ice mode is not present in observations from a holographic probe. This raises the possibility that the small ice observed by optical array probes may at least be in part an instrument artifact due to the counting of out-of-focus large particles as small ice. The concentrations of ice crystals were a factor ~10 higher in the actively growing cloud with the stronger updrafts, with a mean concentration of 261 L−1 compared to 29 L−1 in the decaying case. Particles larger than 700 µm were largely absent from the decaying cirrus case. A comparison with ice-nucleating particle parameterizations suggests that for the developing case the ice concentrations at the lowest temperatures are best explained by homogenous nucleation. ©2016. The Authors. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/62808
Appears in Collections: 影响、适应和脆弱性 气候减缓与适应
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作者单位: School of Earth, Atmospheric and Environmental Sciences, University of Manchester, Manchester, United Kingdom; Met Office, Exeter, United Kingdom; Particle Chemistry Department, Max Planck Institute for Chemistry, Mainz, Germany; Institute for Atmospheric Physics, Johannes Gutenberg University, Mainz, Germany; Department of Physics, Imperial College London, London, United Kingdom
Recommended Citation:
O'Shea S.J.,Choularton T.W.,Lloyd G.,et al. Airborne observations of the microphysical structure of two contrasting cirrus clouds[J]. Journal of Geophysical Research: Atmospheres,2016-01-01,121(22)