Evolution of aerosol optical thickness over Europe during the August 2003 heat wave as seen from CHIMERE model simulations and POLDER data
Evolution of aerosol optical thickness over Europe during the August 2003 heat wave as seen from CHIMERE model simulations and POLDER data
复制标题
从 CHIMERE 模型模拟和 POLDER 数据可以看出 2003 年 8 月热浪期间欧洲上空气溶胶光学厚度的演变
DOI：
10.5194/acp-6-1853-2006
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发表时间：
2005
影响因子：
6.3
通讯作者：
P. Couvert
中科院分区：
文献类型：
--
作者：
A. Hodzic;R. Vautard;H. Chepfer;P. Goloub;L. Menut;P. Chazette;J. Deuze;A. Apituley;P. Couvert
本文利用地球反射偏振与定向（POLDER）传感器在865 nm测量的气溶胶光学厚度（AOTs）和CHIMERE化学输运模型的模拟，描述了2003年8月发生的大规模污染事件中大气气溶胶负荷。在此期间，许多过程（停滞、光化学、森林火灾）导致了异常高的粒子浓度和光学厚度。观测/模拟的AOT比较有助于理解模式重现卫星数据中观测到的大部分AOT特征的能力，在因子2范围内大致一致，相关性在0.4-0.6范围内。然而，当使用常规人为源时，忽略了一些重要的气溶胶特征。另外的模拟，包括在葡萄牙发生的野火的排放和烟雾的高空运输，表明这些过程可能主导某些地区的AOT信号。我们的结果还强调了比较模拟和polder导出的aot的困难，因为在这两种情况下都有很大的不确定性。观测到的AOT值明显低于模拟值（30-50%）。他们与地面太阳光度计气溶胶机器人网络（AERONET）测量结果的比较表明，对于这里考虑的欧洲站点，polder衍生的气溶胶水平被低估了1到2之间的因子。与POLDER aot相比，AERONET aot在模拟中表现更好（没有特别的偏差）。
This study describes the atmospheric aerosol load encountered during the large-scale pollution episode that occurred in August 2003, by means of the aerosol optical thicknesses (AOTs) measured at 865 nm by the Polarization and Directionality of the Earth's Reflectances (POLDER) sensor and the simulation by the CHIMERE chemistry-transport model. During this period many processes (stagnation, photochemistry, forest fires) led to unusually high particle concentrations and optical thicknesses. The observed/simulated AOT comparison helps understanding the ability of the model to reproduce most of the gross AOT features observed in satellite data, with a general agreement within a factor 2 and correlations in the 0.4–0.6 range. However some important aerosol features are missed when using regular anthropogenic sources. Additional simulations including emissions and high-altitude transport of smoke from wildfires that occurred in Portugal indicate that these processes could dominate the AOT signal in some areas. Our results also highlight the difficulties of comparing simulated and POLDER-derived AOTs due to large uncertainties in both cases. Observed AOT values are significantly lower than the simulated ones (30–50%). Their comparison with the ground-based Sun photometer Aerosol Robotic Network (AERONET) measurements suggests, for the European sites considered here, an underestimation of POLDER-derived aerosol levels with a factor between 1 and 2. AERONET AOTs compare better with simulations (no particular bias) than POLDER AOTs.