摘要
采用WRF-CMAQ模式对2013年9月9～13日珠江口一次典型海陆风过程进行数值模拟,并进一步探讨了在此类型环流系统下,海盐气溶胶及其对大气环境的影响.结果表明:珠江口附近海风环流一般在14:00左右开始形成,17:00左右发展最旺盛,且在珠江口沿岸形成扇形风系.在海陆风环流影响下,珠江三角洲地区陆地上Na^+浓度从17:00开始增加,次日02:00左右达到最大,10:00以后开始下降.海盐气溶胶存在明显的氯亏损现象,其中白天的氯亏损情况远比晚上严重,细粒径的氯亏损情况比粗粒径严重.设置有无海盐气溶胶排放的敏感性试验进行对比研究发现:考虑海盐排放后,珠江口地区HCl,SO_4^(2-),NO_3^-的浓度均有增加,其中,HCl和NO_3^-的增加较多,SO_4^(2-)较少.HCl浓度增加的高值在Cl-高值之前;SO_4^(2-)浓度变化主要受海盐气溶胶排放中的硫酸盐组分影响;NO_3^-浓度变化则主要受氯亏损机制和NO_3^-干沉降过程共同影响.
The influence of sea salt aerosols on atmospheric environment in a typical sea-land-breeze circulation over Pearl River Estuary (PRE) during 9~13 September 2013 was investigated with the simulation based on the WRF-CMAQ modeling. The results indicated that the sea-breeze circulation was initiated at around 14:00 LST (local standard time) and subsequently reached its peak at around 17:00 LST, and formed a fan wind circulation along PRE. The mass concentration of Na+ in the Pearl River Delta (PRD) increased from 17:00 LST and reached the maximum value at around 02:00 LST the next day, then gradually decreased after 10:00 LST. The substantial chloride depletion was observed for the sea salt aerosols with more depletion being seen during daytime than nighttime, and more depletion for fine particles than coarse particles. Sensitivity experiments were respectively conducted with and without the emissions of sea salt aerosols in the model system. The results showed that the mass concentrations of HCl, SO4^2-, and NO3^- all increased with the emissions and more increases were seen for HCl and NO3- than for SO4^2-. The peak concentration of HCl arrived earlier than that of Cl^-. The SO4^2- concentration was mainly affected by the sulfate component in the emitted sea salt aerosols, while the NO3^- concentration was mainly affected by both the chloride depletion and its dry deposition.
作者
沈傲
田春艳
刘一鸣
申冲
陈晓阳
陈训来
王明洁
蓝静
樊琦
SHEN Ao;TIAN Chun-yan;LIU Yi-ming;SHEN Chong;CHEN Xiao-yang;CHEN Xun-lai;WANG Ming-jie;LAN Jing;FAN Qi(School of Atmospheric Sciences, Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Guangzhou 510275, China;Shenzhen National Climate Observatory, Shenzhen 518040, China;Guangzhou Climate and Agrometeorology Center, Guangzhou 511430, China)
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2019年第4期1427-1435,共9页
China Environmental Science
基金
国家重点研发计划大气专项课题(2017YFC0210105
2016YFC0203305
2016YFC0203600)
深圳市科技计划项目(JCYJ20170306150333250)
国家自然科学基金资助项目(91544102
41630422)
气象行业专项项目(GYHY201406031)
关键词
珠江口
海陆风环流
海盐气溶胶
氯亏损
数值模拟
Pearl River Estuary
sea-land-breeze circulation
sea salt aerosols
chloride depletion
numerical simulation
