摘要
利用WRF-Chem模式及不同植被覆盖率的敏感试验,模拟了内蒙古地区一次典型沙尘过程,研究了植被覆盖率对沙尘天气强度演变及远距离传输的影响。结果表明:WRF-Chem模式能较好地再现实际沙尘输送过程。沙源地植被覆盖率增加5%,起沙总量削减50%,下游地区地面沙尘浓度的削减>80%,PM10与PM2.5浓度的削减接近或超过80%,空气质量由严重污染降低到轻度污染,有效改善了大气环境;植被覆盖率增加≥15%,大粒径沙粒对起沙量的贡献率逐渐增加,沙尘输送过程中沉降速率增大,导致下游地区沙尘天气峰值浓度出现时间提前。初步得出结论:植被覆盖率增加,叶面积指数增大,植被对细粒子的捕获作用增强。所以,植树造林等荒漠化治理工作应该首先在细粒子为主的半荒漠化地区开展。
The typical dust behavior in Inner Mongolia with different vegetation coverages was simulated using the Weather Research and Forecasting model coupled with Chemistry(WRF-Chem)and sensitive tests.The influence of vegetation coverage on the evolution of the dust weather intensity and long-distance dust movement was investigated.The results show that WRF-Chem can better reproduce actual dust movement.Moreover,the sensitivity experiments with different vegetation coverages reduced 50%of the total dust when the vegetation coverage of the sand source was increased by 5%.Additionally,the reduction of the surface dust concentration,including PM10 and PM2.5,in the downstream area was over or nearly 80%.The air quality improved from severe to light pollution,demonstrating effective atmospheric environment improvement.When the vegetation coverage was increased by 15%or more,the contributionto the sand emission flux of the large-grained sand particles gradually increased,and the sedimentation rate increased during dust transportation,increasing the peak dust concentration at downstream areas.As the vegetation coverage increased,the leaf area index increased,and the vegetation’s capture effect of fine particles was enhanced.Thus,it can be concluded that desertification control projects,such as afforestation,should first be performed in partially deserted areas with fine dust particles.
作者
衣娜娜
姜学恭
董祝雷
樊茹霞
史金丽
YI Nana;JIANG Xuegong;DONG Zhulei;FAN Ruxia;SHI Jinli(Weather Modification Center of Inner Mongolia,Hohhot 010000;Meteorological Research Institute of Inner Mongolia,Hohhot 010000;Regional Meteorological Observatory of Inner Mongolia,Hohhot 010000;Inner Mongolia Region Climate Centre,Hohhot 010000)
出处
《大气科学》
CSCD
北大核心
2024年第2期521-538,共18页
Chinese Journal of Atmospheric Sciences
基金
国家自然科学基金项目41965003
内蒙古自治区自然科学基金项目2021MS04026。
