PDF(Pubmed)
Abstract：
A sequence of dust intrusions occurred from the Sahara Desert to the central Mediterranean in the second half of June 2021. This event was simulated by means of the Weather Research and Forecasting coupled with chemistry (WRF-Chem) regional chemical transport model (CTM). The population exposure to the dust surface PM2.5 was evaluated with the open-source quantum geographical information system (QGIS) by combining the output of the CTM with the resident population map of Italy. WRF-Chem analyses were compared with spaceborne aerosol observations derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) and, for the PM2.5 surface dust concentration, with the Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2) reanalysis. Considering the full-period (17-24 June) and area-averaged statistics, the WRF-Chem simulations showed a general underestimation for both the aerosol optical depth (AOD) and the PM2.5 surface dust concentration. The comparison of exposure classes calculated for Italy and its macro-regions showed that the dust sequence exposure varies with the location and entity of the resident population amount. The lowest exposure class (up to 5 µg m-3) had the highest percentage (38%) of the population of Italy and most of the population of north Italy, whereas more than a half of the population of central, south and insular Italy had been exposed to dust PM2.5 in the range of 15-25 µg m-3. The coupling of the WRF-Chem model with QGIS is a promising tool for the management of risks posed by extreme pollution and/or severe meteorological events. Specifically, the present methodology can also be applied for operational dust forecasting purposes, to deliver safety alarm messages to areas with the most exposed population.
摘要：
2021年6月下半月，从撒哈拉沙漠到地中海中部发生了一系列尘埃入侵。此事件是通过天气研究和预报以及化学（WRF-Chem）区域化学传输模型（CTM）模拟的。通过将CTM的输出与意大利常住人口图相结合，使用开源量子地理信息系统（QGIS）评估了灰尘表面PM2.5的人口暴露。WRF-Chem分析与来自中分辨率成像光谱辐射计（MODIS）的星载气溶胶观测值进行了比较，对于PM2.5表面粉尘浓度，随着现代时代对研究和应用的回顾性分析，版本2（MERRA-2）重新分析。考虑到整个期间(6月17日至24日)和面积平均统计数据，WRF-Chem模拟显示，气溶胶光学深度（AOD）和PM2.5表面粉尘浓度普遍低估。对意大利及其宏观区域计算的暴露类别的比较表明，粉尘序列暴露随常住人口数量的位置和实体而变化。最低的暴露等级（高达5µgm-3）在意大利和意大利北部的大多数人口中所占比例最高（38％），而中部一半以上的人口，意大利南部和岛屿已经暴露在15-25µgm-3范围内的灰尘PM2.5中。WRF-Chem模型与QGIS的耦合是管理极端污染和/或严重气象事件带来的风险的有前途的工具。具体来说,本方法也可以应用于业务粉尘预报目的，向暴露人口最多的地区发送安全警报信息。
