DOI: 10.1002/2017JD026535
Scopus记录号: 2-s2.0-85041037018
论文题名: The Influence of Aerosol Hygroscopicity on Precipitation Intensity During a Mesoscale Convective Event
作者: Kawecki S. ; Steiner A.L.
刊名: Journal of Geophysical Research: Atmospheres
ISSN: 2169897X
出版年: 2018
卷: 123, 期: 1 起始页码: 424
结束页码: 442
语种: 英语
英文关键词: aerosols
; hygroscopicity
; mesoscale convective system
; microphysics
; precipitation
; WRF-Chem
Scopus关键词: aerosol
; aerosol composition
; atmospheric convection
; cloud microphysics
; cold pool
; hygroscopicity
; mesoscale meteorology
; model
; precipitation intensity
; simulation
; updraft
; weather forecasting
英文摘要: We examine how aerosol composition affects precipitation intensity using the Weather and Research Forecasting Model with Chemistry (version 3.6). By changing the prescribed default hygroscopicity values to updated values from laboratory studies, we test model assumptions about individual component hygroscopicity values of ammonium, sulfate, nitrate, and organic species. We compare a baseline simulation (BASE, using default hygroscopicity values) with four sensitivity simulations (SULF, increasing the sulfate hygroscopicity; ORG, decreasing organic hygroscopicity; SWITCH, using a concentration-dependent hygroscopicity value for ammonium; and ALL, including all three changes) to understand the role of aerosol composition on precipitation during a mesoscale convective system (MCS). Overall, the hygroscopicity changes influence the spatial patterns of precipitation and the intensity. Focusing on the maximum precipitation in the model domain downwind of an urban area, we find that changing the individual component hygroscopicities leads to bulk hygroscopicity changes, especially in the ORG simulation. Reducing bulk hygroscopicity (e.g., ORG simulation) initially causes fewer activated drops, weakened updrafts in the midtroposphere, and increased precipitation from larger hydrometeors. Increasing bulk hygroscopicity (e.g., SULF simulation) simulates more numerous and smaller cloud drops and increases precipitation. In the ALL simulation, a stronger cold pool and downdrafts lead to precipitation suppression later in the MCS evolution. In this downwind region, the combined changes in hygroscopicity (ALL) reduces the overprediction of intense events (>70 mm d−1) and better captures the range of moderate intensity (30–60 mm d−1) events. The results of this single MCS analysis suggest that aerosol composition can play an important role in simulating high-intensity precipitation events. ©2017. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/114713
Appears in Collections: 气候减缓与适应
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作者单位: Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, MI, United States
Recommended Citation:
Kawecki S.,Steiner A.L.. The Influence of Aerosol Hygroscopicity on Precipitation Intensity During a Mesoscale Convective Event[J]. Journal of Geophysical Research: Atmospheres,2018-01-01,123(1)