Regional modelling of Saharan dust and biomass-burning smoke
Regional modelling of Saharan dust and biomass-burning smoke
复制标题
撒哈拉尘埃和生物质燃烧烟雾的区域模型
DOI：
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发表时间：
2011
期刊：
影响因子：
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通讯作者：
M. Wendisch
中科院分区：
文献类型：
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作者：
B. Heinold;I. Tegen;S. Bauer;M. Wendisch
本文以2008年1月和2月SAMUM-2野外活动为例，介绍了撒哈拉沙尘和生物质燃烧气溶胶颗粒引起的直接辐射强迫和动态大气响应。使用cosmos - muscat区域模式系统。它允许计算的尘埃和烟雾负荷与太阳和地面辐射以及与模型动力学在线交互。根据佛得角地区的空气辐射测量值评估了向上太阳辐照度的模式结果。对比表明，在烟尘混合的情况下，两者具有较好的一致性。尘埃和烟雾粒子通过改变辐射加热速率来影响大气动力学。相关的压力扰动改变了局地尺度和天气尺度的气流模式。在辐射反馈模拟中，哈德利环流增强，几内亚沿岸出现辐合带。因此，烟雾颗粒向北扩散了5°以上，减少了向赤道的传输。在辐合带内，撒哈拉沙尘和生物质燃烧物质更有效地向佛得角平流。考虑到模式的不确定性，当考虑气溶胶与辐射的相互作用时，模拟的气溶胶分布与观测的气溶胶分布之间的一致性得到了局部改善。
The direct radiative forcing and dynamic atmospheric response due to Saharan dust and biomass-burning aerosol particles are presented for a case study during the SAMUM-2 field campaign in January and February 2008. The regional model system COSMO-MUSCAT is used. It allows online interaction of the computed dust and smoke load with the solar and terrestrial radiation and with the model dynamics. Model results of upward solar irradiances are evaluated against airborne radiation measurements in the Cape Verde region. The comparison shows a good agreement for the case of dust and smoke mixture. Dust and smoke particles influence the atmospheric dynamics by changing the radiative heating rates. The related pressure perturbations modify local and synoptic scale air-flow patterns. In the radiative feedback simulations, the Hadley circulation is enhanced and convergence zones occur along the Guinea coast. Thus, the smoke particles spread more than 5◦ further north and the equatorward transport is reduced. Within the convergence zones, Saharan dust and biomass-burning material are more effectively advected towards the Cape Verdes. Given the model uncertainties, the agreement between the modelled and observed aerosol distribution is locally improved when aerosol–radiation interaction is considered.