摘要
本文利用能量闭合的二维非线性,非定常模式,结合地面热量平衡方程,研究了夜间城市边界层和气溶胶的相互作用问题。结果表明:气溶胶在夜间对大气低层起保温作用,对大气上层起冷却作用,使大气低层稳定度减小,上层稳定度增加;此外,气溶胶还能够削弱贴地逆温强度。在正常城市气溶胶污染情况下,气溶胶对城市热岛强度影响不大,但可使城市热岛环流稍有增加。夜间城市边界层对气溶胶的反馈作用使大气下层气溶胶浓度减小,上层气溶胶浓度增加。上述部分结论得到了在天津取得的城市热岛观测资料的直接验证。
Combining with the surface heat balance equation,a nonlinear and unsteady two-dimension-al numerical model,which is closed by energy method,has been used to study the interaction be-tween nocturnal urban boundary layer and aerosols.The results show that the effect of aerosolsare to warm up the low boundary layer and cool down the upper boundary layer at night;aerosolsdecrease the stability of low boundary layer and increase the stability of upper boundary layer.Inaddition,aerosols can decrease the intensity of inversion close to ground.In the city polluted nor-mally by aerosols,the influence of aerosols on the intensity of urban heat island isn't large,butthey can increase slightly urban heat island circulation。The feedback effect of nocturnal urbanboundary layer on aerosols is to decrease aerosol concentrations in the low boundary layer and in-crease in the upper.Part of the above conclusions are verified by the observational data on urbanheat island in Tianjin city.
出处
《应用气象学报》
CSCD
北大核心
1992年第1期32-41,共10页
Journal of Applied Meteorological Science
