DOI: 10.1029/2018JD028365
Scopus记录号: 2-s2.0-85049866180
论文题名: Accuracy Required in Measurements of Refractive Index and Hygroscopic Response to Reduce Uncertainties in Estimates of Aerosol Radiative Forcing Efficiency
作者: Valenzuela A. ; Reid J.P. ; Bzdek B.R. ; Orr-Ewing A.J.
刊名: Journal of Geophysical Research: Atmospheres
ISSN: 2169897X
出版年: 2018
卷: 123, 期: 12 起始页码: 6469
结束页码: 6486
语种: 英语
英文关键词: hygroscopic kappa parameter
; radiative forcing efficiency
; real and imaginary refractive indices
; relative humidity
Scopus关键词: absorption
; accuracy assessment
; aerosol
; ammonium sulfate
; brown carbon
; estimation method
; hygroscopicity
; measurement method
; parameterization
; radiative forcing
; refractive index
; relative humidity
; uncertainty analysis
英文摘要: The magnitude of aerosol radiative forcing resulting from the scattering and absorption of radiation is still uncertain. Sources of uncertainty include the physical and optical properties of aerosol, reflected in uncertainties in real and imaginary refractive indices (n and k) and relative humidity (RH). The effect of RH on the geometrical size of aerosol particles is often reported as a hygroscopic kappa parameter (κ). The objective of this study is to explore the sensitivity of radiative forcing efficiency (RFE) to changes in particle properties in order to better define the accuracy with which optical and hygroscopic measurements must be made to reduce uncertainties in RFE. Parameterizations of precise values of n and k are considered as functions of RH for ammonium sulfate (AS) and brown carbon (BrC). The range of the RFE estimated for typical uncertainties of n and κ for AS of 0.1 μm dry radius is less than ±7% and is not affected by an increase of RH. For typical sizes of AS in the atmosphere (0.35 μm dry radius), the range of the RFE increases to ±20% at 90% RH and ±15% at 99% RH. Absorbing small BrC particles (0.1 μm dry radius) cause cooling at the top of the atmosphere, and as RH and κ increase, the RFE is more negative compared to the usual assumptions of dry unhygroscopic BrC. For larger BrC particles (0.35 μm dry radius), the change in RFE for RHs ~100% compared to dry conditions can take values around −100%. ©2018. 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/113681
Appears in Collections: 气候减缓与适应
There are no files associated with this item.
作者单位: School of Chemistry, University of Bristol, Bristol, United Kingdom
Recommended Citation:
Valenzuela A.,Reid J.P.,Bzdek B.R.,et al. Accuracy Required in Measurements of Refractive Index and Hygroscopic Response to Reduce Uncertainties in Estimates of Aerosol Radiative Forcing Efficiency[J]. Journal of Geophysical Research: Atmospheres,2018-01-01,123(12)