A novel method for calculating ambient aerosol liquid water content based on measurements of a humidified nephelometer system
A novel method for calculating ambient aerosol liquid water content based on measurements of a humidified nephelometer system
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一种基于加湿浊度计系统测量计算环境气溶胶液态水含量的新方法
DOI：
10.5194/amt-11-2967-2018
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发表时间：
2017-10
影响因子：
3.8
通讯作者：
Zhao CS
中科院分区：
文献类型：
--
作者：
Kuang Ye;Tao Jiang Chuan;Ma Nan;Zhao Chun Sheng;Zhao Gang;Xu Wanyun;Bian Yu Xuan;Zhao CS
大气气溶胶粒子上凝结的水汽在大气环境、大气化学和气候等方面具有重要的意义。在此之前，没有仪器可用于实时监测环境气溶胶液态水含量（ALWC）。本文提出了一种基于三波长增湿浊度计系统测量的大气有效层厚度的新方法，该系统测量了干燥状态和不同相对湿度条件下三个波长的气溶胶光散射系数和后向散射系数，提供了光散射增强因子的测量结果。所提出的ALWC计算方法包括两个步骤：第一步是基于“干”浊度计的测量值，使用称为随机森林模型的机器学习方法估计环境气溶胶颗粒的干状态总体积浓度（干）。估计的（干）与测量的一致。第二步是使用相对湿度（RH）和朗格斯特伦指数估算由于水吸收引起的环境气溶胶颗粒的体积增长因子Vg（RH）。ALWC由估计值（干）和Vg（RH）计算。为了验证新方法的有效性，将谷城战役期间增湿浊度计系统测量值计算的环境ALWC与ISORROPIA热力学模型使用气溶胶化学数据计算的环境ALWC进行了比较。获得了良好的一致性，斜率和截距分别为1.14和8.6 µmcm（0.92）。这种新方法的优点是，环境ALWC可以得到单独的三波长加湿浊度计系统的测量的基础上，方便实时监测环境ALWC和促进气溶胶液态水及其在大气化学，二次气溶胶形成和气候变化的作用的研究。
Water condensed on ambient aerosol particles plays significant roles in atmospheric environment, atmospheric chemistry and climate. Before now, no instruments were available for real-time monitoring of ambient aerosol liquid water contents (ALWCs). In this paper, a novel method is proposed to calculate ambient ALWC based on measurements of a three-wavelength humidified nephelometer system, which measures aerosol light scattering coefficients and backscattering coefficients at three wavelengths under dry state and different relative humidity (RH) conditions, providing measurements of light scattering enhancement factor(RH). The proposed ALWC calculation method includes two steps: the first step is the estimation of the dry state total volume concentration of ambient aerosol particles,(dry), with a machine learning method called random forest model based on measurements of the “dry” nephelometer. The estimated(dry) agrees well with the measured one. The second step is the estimation of the volume growth factor Vg(RH) of ambient aerosol particles due to water uptake, using(RH) and the Ångström exponent. The ALWC is calculated from the estimated(dry) and Vg(RH). To validate the new method, the ambient ALWC calculated from measurements of the humidified nephelometer system during the Gucheng campaign was compared with ambient ALWC calculated from ISORROPIA thermodynamic model using aerosol chemistry data. A good agreement was achieved, with a slope and intercept of 1.14 and8.6 µmcm(0.92), respectively. The advantage of this new method is that the ambient ALWC can be obtained solely based on measurements of a three-wavelength humidified nephelometer system, facilitating the real-time monitoring of the ambient ALWC and promoting the study of aerosol liquid water and its role in atmospheric chemistry, secondary aerosol formation and climate change.
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华北平原夏季气溶胶吸湿增长对气溶胶直接辐射效应的影响
影响因子：
5
作者：
Ye Kuang;Chunsheng Zhao;Jiangchuan Tao;Yuxuan Bian;Nan Ma
通讯作者：
Nan Ma
影响因子：
2.2
作者：
T. Anderson;D. Covert;S. F. Marshall;M. L. Laucks;R. Charlson;A. Waggoner;J. Ogren;R. Caldow;R. L. Holm;F. R. Quant;G. Sem;A. Wiedensohler;N. Ahlquist;T. Bates
通讯作者：
T. Anderson;D. Covert;S. F. Marshall;M. L. Laucks;R. Charlson;A. Waggoner;J. Ogren;R. Caldow;R. L. Holm;F. R. Quant;G. Sem;A. Wiedensohler;N. Ahlquist;T. Bates
影响因子：
4.5
作者：
D. Rader;P. Mcmurry
通讯作者：
D. Rader;P. Mcmurry
华北平原高相对湿度气溶胶颗粒吸湿特性及其日变化
影响因子：
6.3
作者：
Liu, P. F.;Zhao, C. S.;Wiedensohler, A.
通讯作者：
Wiedensohler, A.
DOI：
10.1007/978-1-4419-9326-7_5
发表时间：
2012-01-01
期刊：
ENSEMBLE MACHINE LEARNING: METHODS AND APPLICATIONS
影响因子：
--
作者：
Cutler, Adele;Cutler, D. Richard;Stevens, John R.
通讯作者：
Stevens, John R.