...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Geophysical Research. Biogeosciences >Dependence of aerosol light absorption and single-scattering albedo on ambient relative humidity for sulfate aerosols with black carbon cores
【24h】

Dependence of aerosol light absorption and single-scattering albedo on ambient relative humidity for sulfate aerosols with black carbon cores

机译：含黑碳芯的硫酸盐气溶胶的气溶胶光吸收和单散射反照率对环境相对湿度的依赖性

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Atmospheric aerosols frequently contain hygroscopic sulfate species and black carbon (soot) inclusions. In this paper we report results of a modeling study to determine the change in aerosol absorption due to increases in ambient relative humidity (RH), for three common sulfate species, assuming that the soot mass fraction is present as a single concentric core within each particle. Because of the lack of detailed knowledge about various input parameters to models describing internally mixed aerosol particle optics, we focus on results that were aimed at determining the maximum effect that particle humidification may have on aerosol light absorption. In the wavelength range from 450 to 700 nm, maximum absorption humidification factors (ratio of wet to "dry=30% RH" absorption) for single aerosol particles are found to be as large as 1.75 when the RH changes from 30 to 99.5%. Upon lesser humidification from 30 to 80% RH, absorption humidification for single particles is only as much as 1.2, even for the most favorable combination of initial ("dry") soot mass fraction and particle size. Integrated over monomodal lognormal particle size distributions. maximum absorption humidification factors range between 1.07 and 1.15 for humidification from 30 to 80% and between 1.1 and 1.35 for humidification from 30 to 95% RH for all species considered. The largest humidification factors at a wavelength of 450 nm are obtained for "dry" particle size distributions that peak at a radius of 0.05 mum, while the absorption humidification factors at 700 nm are largest for "dry" size distributions that are dominated by particles in the radius range of 0.06 to 0.08 mum. Single-scattering albedo estimates at ambient conditions are often based on absorption measurements at low RH (similar to 30%) and the assumption that aerosol absorption does not change upon humidification (i.e., absorption humidification equal to unity). Our modeling study suggests that this assumption alone can introduce absolute errors in estimates of the midvisible single-scattering albedo of up to 0.05 for realistic dry particle size distributions. Our study also indicates that this error increases with increasing wavelength. The potential errors in aerosol single-scattering albedo derived here are comparable in magnitude and in addition to uncertainties in single-scattering albedo estimates that are based on measurements of aerosol light absorption and scattering. [References: 18]
机译：大气气溶胶经常含有吸湿性硫酸盐和黑碳（烟灰）夹杂物。在本文中，我们报告了一种模型研究的结果，用于确定三种常见硫酸盐物种由于环境相对湿度（RH）的增加而引起的气溶胶吸收变化，假设烟灰质量分数作为每个颗粒中的单个同心核心存在。由于缺乏有关描述内部混合气溶胶粒子光学模型的各种输入参数的详细知识，因此我们专注于旨在确定粒子加湿对气溶胶光吸收的最大影响的结果。在450到700 nm的波长范围内，当相对湿度从30变为99.5％时，单个气溶胶颗粒的最大吸收增湿因子（湿比与“干比= 30％RH”的吸收比）被发现高达1.75。在从30％RH降低到80％RH的情况下，即使对于初始（“干”）烟灰质量分数和粒度的最佳组合，单个颗粒的吸收增湿也仅为1.2。整合了单峰对数正态粒度分布。对于所考虑的所有物种，最大吸收增湿因子的相对湿度从30％到80％介于1.07和1.15之间，相对湿度从30％到95％介于1.1到1.35之间。对于“干”粒径分布在半径为0.05 mum处达到峰值的情况，在450 nm波长处获得最大的增湿因子，而对于“干”粒径分布以700 nm的吸收增湿因子最大，而“干”粒径分布中的颗粒占主导地位。半径范围为0.06到0.08微米。在环境条件下的单散射反照率估算通常基于低RH（大约30％）下的吸收率测量值以及假设气溶胶吸收量在加湿后不会改变的假设（即吸收湿度等于1）。我们的模型研究表明，仅此一个假设就可以在实际干颗粒尺寸分布的中可见性单散射反照率估计高达0.05时引入绝对误差。我们的研究还表明，该误差随着波长的增加而增加。此处得出的气溶胶单散射反照率的潜在误差在大小上是可比的，此外还有基于气溶胶光吸收和散射测量的单散射反照率估计的不确定性。 [参考：18]

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号