Continuous observations of Asian dust and other aerosols by polarization lidars in China and Japan during ACE-Asia
Continuous observations of Asian dust and other aerosols by polarization lidars in China and Japan during ACE-Asia
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DOI：
10.1029/2002jd003253
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发表时间：
2004-10
影响因子：
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通讯作者：
A. Shimizu;N. Sugimoto;I. Matsui;K. Arao;I. Uno;T. Murayama;N. Kagawa;Kazuma Aoki;A. Uchiyama-A.-Uc
中科院分区：
文献类型：
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作者：
A. Shimizu;N. Sugimoto;I. Matsui;K. Arao;I. Uno;T. Murayama;N. Kagawa;Kazuma Aoki;A. Uchiyama-A.-Uc
[1]利用偏振激光雷达在2001年3 - 5月对中国和日本的气溶胶进行了连续观测，与亚太区域气溶胶特征试验（ACE-Asia）野外活动期相对应。北京、长崎和筑波的激光雷达在任何天气条件下都持续运行。在垂直剖面上对大气中的散射体进行分类，计算了6 km范围内的尘埃、球形气溶胶和云的出现频率。在整个高度范围内，北京的沙尘频率最高。长崎的地面附近有一个沙尘发生的高峰。在筑波的自由对流层中经常检测到灰尘。在假设尘埃和球形气溶胶混合的情况下，从退极化比估计了尘埃和球形气溶胶对总后向散射系数的贡献。尘埃和球形气溶胶后向散射的垂直分布曲线代表了这两种气溶胶的不同特征。北京、长崎和筑波的月平均后向散射系数分别为0.003/km/sr、0.001 ~ 0.002/km/sr和0.0006/km/sr。近地表球形气溶胶后向散射系数均为0.002 ~ 0.004/km/sr。我们将导出的后向散射系数与化学天气预报系统（CFORS）计算的气溶胶质量浓度进行了比较。CFORS很好地再现了高沙尘事件的垂直结构和整个观测期内球形气溶胶的增强。利用5台激光雷达对2001年5月16日至19日在日本发生的一次沙尘事件进行了分析，描述了沙尘的精细结构。
[1] Continuous observations of aerosols in China and Japan were made by polarization lidars during March to May 2001, corresponding with the Asian Pacific Regional Aerosol Characterization Experiment (ACE-Asia) field campaign period. Lidars in Beijing, Nagasaki, and Tsukuba were continuously operated regardless of weather conditions. Scatterers in the atmosphere were categorized for all vertical profiles, and occurrence frequencies of dust, spherical aerosols, and clouds up to 6 km were calculated. The frequency of dust was highest in Beijing for the whole height range. There was a peak of dust occurrence near the ground in Nagasaki. Dust was frequently detected in the free troposphere in Tsukuba. The contributions of dust and spherical aerosols to the total backscattering coefficient were estimated from the depolarization ratio with the assumption of the external mixture of both kinds of aerosols. Vertical profiles of backscattering by dust and by spherical aerosols represented the different characteristics of these aerosols. The monthly averaged backscattering coefficients by dust near the surface were 0.003/km/sr in Beijing, 0.001–0.002/km/sr in Nagasaki, and 0.0006/km/sr in Tsukuba. The backscattering coefficients by spherical aerosols near the surface were 0.002–0.004/km/sr at all three observatories. We compared the derived backscattering coefficients with aerosol mass concentrations calculated by a numerical model, Chemical Weather Forecasting System (CFORS). CFORS reproduced well the vertical structures of the tall dust events and the enhancements of spherical aerosols throughout the observation period. A specific dust event on 16–19 May 2001 was analyzed by using five lidars in Japan, and its fine structure is described.