【摘要】 利用中尺度模式MM5对2009年冬季山西省一场持续30多个小时的罕见浓雾过程进行模拟.结果表明,山西省气象局现行的MM5设计方案对雾区的模拟结果与实测结果基本一致,但夜间近地层的温度存在冷偏差,相对湿度偏高.另外,由于山西省空气污染较重,空气中的粒子数对能见度的影响不能忽略,因此仅用能见度(Vis)与液态水含量(LWC)的参数化方案估算的能见度,只有在浓雾时才与实测一致,具有很大的局限性;而利用能见度(Vis)与相对湿度(RH)的参数化方案估算的能见度比实测值偏大,但在能见度的趋势预报上与实测值基本一致.用太原机场的实测资料对Vis-RH关系式进行修订后,其估算的能见度更加准确,可以为业务预报提供参考.更多还原

【Abstract】 An unusual dense fog event,occuring in Shanxi province in winter and lasting more than 30 hours,was simulated by a mesoscale model MM5. The results showed that the fog regions simulated by the current configuration of MM5 used in Shanxi Meteorological Bureau was consistent with the observations,but the liquid water content was overestimated in generally. Corresponding with that,the temperature near surface had a cold bias and the relative humidity had a positive bias. Due to the severe air pollution in Shanxi,the influence of particles on the visibility couldn’t be ignored,the visibility was underestimated by the Vis-LWC parameterization than the observation. Though the Vis-RH parameterization overestimated visibility than observation,it could predict the actual tendency of visibility. The revised Vis-RH parameterization by actual observation values of Taiyuan Airport was more accurate,which can provide reference for visibility forecast.更多还原