Wet deposition in a global size-dependent aerosol transport model. 2. Influence of the scavenging scheme on 210Pb vertical profiles, surface concentrations, and deposition
Wet deposition in a global size-dependent aerosol transport model. 2. Influence of the scavenging scheme on 210Pb vertical profiles, surface concentrations, and deposition
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全球尺寸相关气溶胶传输模型中的湿沉降。
DOI：
10.1029/98jd01826
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发表时间：
1998
期刊：
影响因子：
--
通讯作者：
F. Dulac
中科院分区：
文献类型：
--
作者：
W. Guelle;Y. Balkanski;J. Dibb;M. Schulz;F. Dulac
亚微米级气溶胶的主要大气汇是湿法去除。铅210是222Rn的放射性衰变产物，在形成亚微米粒子后立即附着。在这里，我们使用一个离线的、尺寸分辨的全球大气输送模式，比较了全球气溶胶模拟中使用的三种不同的湿清除方案对2.OPB气溶胶分布的影响。我们着重介绍了每种清扫计划在复制现有测量数据方面的优缺点，这些测量数据包括地面空气和沉积物中的浓度以及在北美和北太平洋西部和中部观测到的垂直剖面。我们表明，总沉降量的模型测量比较不允许区分清除方案，因为补偿效应可以掩盖它们各自清除效率的差异。清除参数的差异对气溶胶垂直分布的影响比地面浓度的影响要大得多。根据清扫公式，模型得出的不同海拔的纬向平均浓度相差3倍以上，只有一种方案使我们能够可靠地再现观察到的个别剖面。这项研究表明，仅靠地面测量不足以验证全球气溶胶输送模型。
The main atmospheric sink for submicron aerosols is wet removal. Lead 210, the radioactive decay product of 222Rn, attaches immediately after being formed to submicron particles. Here we compare the effects of three different wet-scavenging schemes used in global aerosol simulations on the 2•oPb aerosol distribution using an off-line, size-resolved, global atmospheric transport model. We highlight the merits and shortcomings of each scavenging scheme at reproducing available measurements, which include concentrations in surface air and deposition, as well as vertical profiles observed over North America and western and central North Pacific. We show that model-measurement comparison of total deposition does not allow to distinguish between scavenging schemes because compensation effects can hide the differences in their respective scavenging efficiencies. Differences in scavenging parameterization affect the aerosol vertical distribution to a much greater extent than the surface concentration. Zonally averaged concentrations at different altitudes derived from the model vary by more than a factor of 3 according to the scavenging formulation, and only one scheme enables us to reproduce reliably the individual profiles observed. This study shows that ground measurements alone are insufficient to validate a global aerosol transport model.