Short-term variation in atmospheric constituents associated with local front passage observed by a 3-D coherent Doppler lidar and in-situ aerosol/gas measurements
Short-term variation in atmospheric constituents associated with local front passage observed by a 3-D coherent Doppler lidar and in-situ aerosol/gas measurements
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通过 3D 相干多普勒激光雷达和现场气溶胶/气体测量观测到的与局部锋面通道相关的大气成分的短期变化
DOI：
10.1016/j.aeaoa.2019.100043
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发表时间：
2019
影响因子：
--
通讯作者：
Akihiro Yamazaki
中科院分区：
文献类型：
--
作者：
Hisahiro Takashima;Keiichiro Hara;Chiharu Nishita-Hara;Yasushi Fujiyoshi;Koichi Shiraishi;Masahiko Hayashi;Ayako Yoshino;Akinori Takami;Akihiro Yamazaki
局地锋面，如海风和陆风锋面，不仅在气象方面，而且在污染物的运输和混合方面，特别是在城市地区，发挥着重要作用。由于三维风场测量的困难，很少有研究关注与局地锋面通道相关的气溶胶和气体成分的短期精细尺度时空变化。2016年11月底，在日本城市福冈市（33.55°N, 130.37°E）安装了一台三维相干多普勒激光雷达，此后连续测量了三维风场。2017年5月3日和6月29日观测到两个具有典型密度流结构的局地锋。2017年5月3日，在当地锋面经过处，气溶胶（特别是较小尺寸的气溶胶）、黑碳（BC）和一氧化碳（CO）的浓度逐步增加，据推测它们来自地表。然而，在海拔越高的地方，o3的含量越高，所以它的含量降低了。在2017年6月29日的另一个案例中，在锋面通过之前，清晨有小雨，所有气体和气溶胶含量都很低。锋面通道气溶胶、BC和CO含量从5月3日开始逐渐增加，但O3含量在日出后逐渐增加，O3变化不明显。多普勒激光雷达垂直气溶胶观测表明，6月29日锋面系统深度（300-400 m）比5月3日（~ 700 m）要薄得多，降温幅度也比5月3日大。这些事实表明，6月29日系统内气团与系统上方或前方气团的混合并不比5月3日强，因此地面的气溶胶和气体含量可能受到系统垂直混合/稀释以及局地排放的强烈影响。
Local fronts, such as sea-breeze and land-breeze fronts, play an important role not only from a meteorological aspect but also for pollutant transport and mixing, in urban areas in particular. Due to the difficulty of measuring three-dimensional (3-D) wind fields, there are few studies focusing on short-term fine-scale spatial and temporal variations in aerosol and gas compositions associated with local front passage. At the end of November 2016, a 3-D coherent Doppler lidar was installed in Fukuoka city (33.55°N, 130.37°E), an urban area in Japan, and 3D-wind fields have been continuously measured since then. Two local fronts with typical density current structure were observed on 3 May and 29 June 2017. On 3 May 2017, there was a stepwise increase in concentrations of aerosol (particularly smaller size aerosol), black carbon (BC) and carbon monoxide (CO), supposedly of surface origin, at the passage of the local front. However, O3content, which can be higher at higher altitudes, decreased. In another case on 29 June 2017, there was light rain in the early morning and all gas and aerosol contents were low before the passage of the front. At the front passage, there was a stepwise increase in aerosol, BC and CO contents as on 3 May, although O3content gradually increased after sunrise and no clear change was observed in O3. Vertical aerosol observations by the Doppler lidar indicate that the depth of the front system on 29 June was much thinner (up to 300–400 m) than that on 3 May (up to ∼700 m), and the temperature decrease was larger than on 3 May. These facts suggest that the mixing of air masses within the system with those above or ahead of the system on 29 June was no stronger than on 3 May, and thus the aerosol and gas contents at the ground may be strongly affected by the vertical mixing/dilution of the system as well as by local emission.
用多普勒激光雷达观察到的条纹结构的性质
影响因子：
4.3
作者：
Ayako Yagi;A. Inagaki;M. Kanda;C. Fujiwara;Y. Fujiyoshi
通讯作者：
Y. Fujiyoshi