View : 129 Download: 0

Mass Extinction Efficiency Approximation for Polydispersed Aerosol Using Harmonic Mean-Type Approximation

Title
Mass Extinction Efficiency Approximation for Polydispersed Aerosol Using Harmonic Mean-Type Approximation
Authors
Um, JunshikJang, SeonghyeonYoon, Young JunLee, Seoung SooLee, Ji YiHan, Kyung ManChoi, Won JunKim, Yong PyoKim, Cheol-HeeJung, Chang Hoon
Ewha Authors
김용표이지이
SCOPUS Author ID
김용표scopus; 이지이scopus
Issue Date
2020
Journal Title
APPLIED SCIENCES-BASEL
ISSN
2076-3417JCR Link
Citation
APPLIED SCIENCES-BASEL vol. 10, no. 23
Keywords
mass extinction efficiencyextinction coefficientpolydispersed aerosolreconstruction methodMie scatteringharmonic mean type approximation
Publisher
MDPI
Indexed
SCIE; SCOPUS WOS scopus
Document Type
Article
Abstract
Among many parameters characterizing atmospheric aerosols, aerosol mass extinction efficiency (MEE) is important for understanding the optical properties of aerosols. MEE is expressed as a function of the refractive indices (i.e., composition) and size distributions of aerosol particles. Aerosol MEE is often considered as a size-independent constant that depends only on the chemical composition of aerosol particles. The famous Malm's reconstruction equation and subsequent revised methods express the extinction coefficient as a function of aerosol mass concentration and MEE. However, the used constant MEE does not take into account the effect of the size distribution of polydispersed chemical composition. Thus, a simplified expression of size-dependent MEE is required for accurate and conventional calculations of the aerosol extinction coefficient and also other optical properties. In this study, a simple parameterization of MEE of polydispersed aerosol particles was developed. The geometric volume-mean diameters of up to 10 mu m with lognormal size distributions and varying geometric standard deviations were used to represent the sizes of various aerosol particles (i.e., ammonium sulfate and nitrate, elemental carbon, and sea salt). Integrating representations of separate small mode and large mode particles using a harmonic mean-type approximation generated the flexible and convenient parameterizations of MEE that can be readily used to process in situ observations and adopted in large-scale numerical models. The calculated MEE and the simple forcing efficiency using the method developed in this study showed high correlations with those calculated using the Mie theory without losing accuracy.
Show the fulltext
DOI
10.3390/app10238637
Appears in Collections:
엘텍공과대학 > 화학신소재공학전공 > Journal papers
Files in This Item:
There are no files associated with this item.
Export
RIS (EndNote)
XLS (Excel)
XML


qrcode

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

BROWSE