采用GFS背景场资料和ADAS资料同化系统,使用WRF模式对2014—2016年青岛近海17个海雾个例进行了模拟,分析了3种能见度算法的预报效果。结果表明, FSL(Forecast Systems Laboratory)算法对于沿海站、岸基站雾的预报较SW99(Steolinga and Warner 1999)算法有优势;对于海岛站而言,SW99算法则优于FSL算法。混合算法CVIS(Combined Visibility)较单一算法预报雾准确率有所提高。3种能见度算法基本上是高估能见度的,SW99算法能见度预报均方根误差最大。另外,SW99算法对沿海站、岸基站雾开始时间预报较实况多偏晚,结束时间预报较实况多偏早,持续时间预报较实况多偏短。
Based on GFS background data and ARPS Data Assimilation System, visibility forecasts of 17 offshore sea fog cases in Qingdao from 2014 to 2016 are analyzed using the WRF model and three visibility algorithms in this paper. The results show that the FSL algorithm has advantages over the SW99 algorithm in forecasting the fog and its start time for coastal stations and shorebased stations, while the latter is better than the former for island stations. The hybrid CVIS algorithm improves the forecast accuracy of fog compared to single algorithm. The three algorithms basically overestimate the visibility, and the SW99 algorithm has the maximum root mean square error in the visibility forecast. In addition, by the SW99 algorithm for coastal stations and shore-based stations, the start time of fog forecast is basically later than the actual time, the end time of forecast earlier, and the duration of forecast shorter.