CAJ | 학술논문

面向对象检验技术是定量降水预报误差分析方法之一，通过对某一降水过程进行分离，实现对其落区、量级等预报误差的定量化分析。基于面向对象的检验方法和天气系统识别技术，本文利用实况观测资料、ECMWF全球数值模式产品，以2012年汛期西南地区5个典型强降水天气过程作为检验对象，对其降水及天气尺度影响系统110d模式预报误差进行了定量化分析。分析表明：在中短期时效内，模式均对西南地区雨带位置预报偏北、偏西，中期时效内偏差更显著，雨带主轴上70％以上的点预报较实况偏北在2°以内，偏西约3°以内；预报的大雨及以上量级降水量较实况偏弱；模式12d预报的极值分布与实况较为接近，随着预报时效延长，预报的极值较实况明显偏小；模式预报的小雨及以下量级的降水范围较实况偏大，对大雨以上量级的降水范围较实况明显偏小。对于四川盆地而言，预报的切变线较零场偏西0．5°3°。低空急流预报偏西0．5°1．5°；低空急流强度预报偏差具有季节差异。
면향대상검험기술시정량강수예보오차분석방법지일，통과대모일강수과정진행분리，실현대기락구、량급등예보오차적정양화분석。기우면향대상적검험방법화천기계통식별기술，본문이용실황관측자료、ECMWF전구수치모식산품，이2012년신기서남지구5개전형강강수천기과정작위검험대상，대기강수급천기척도영향계통110d모식예보오차진행료정양화분석。분석표명：재중단기시효내，모식균대서남지구우대위치예보편북、편서，중기시효내편차경현저，우대주축상70％이상적점예보교실황편북재2°이내，편서약3°이내；예보적대우급이상량급강수량교실황편약；모식12d예보적겁치분포여실황교위접근，수착예보시효연장，예보적겁치교실황명현편소；모식예보적소우급이하량급적강수범위교실황편대，대대우이상량급적강수범위교실황명현편소。대우사천분지이언，예보적절변선교령장편서0．5°3°。저공급류예보편서0．5°1．5°；저공급류강도예보편차구유계절차이。
Object-oriented verification method,which analyzes the bias of location,rain volume for a rain-fall event,is one of the techniques for quantitative precipitation forecast verification.Based on the object-oriented verification method and weather system auto-identification techenique,the errors of the quantita-tive precipitation forecast and synoptic scale system of high-resolution version of the ECMWF medium-range forecast model for 1-10 d of 5 typical severe rainfall cases over Southwest China in 2012 was deter-mined.The results show that:The forecasted rainfall zone for all valid time is located west and north to the observed one,especially for the medium-range forecast.70% points of the forecast rainfall belt over the rainfall axis lie in two degrees north and three degrees west of observed one.The forecasted rainfall in-tensity with amount larger than 25 mm/24 h is weaker than the observed.The distribution of forecasted extreme rainfall is almost the same as the observed in 24-48 h.However,with the valid time becoming longer,the extreme forecasted rainfall gets obviously weaker.Area of forecasted light rain is larger than the observed,but the area of rainfall more than 25 mm/24 h is smaller.For Sichuan Basin,the forecasted shear line is situated 0.5-3 degrees west to the analyzed one,and the forecasted low level jet (LLJ)is lo-cated 0.5-1.5 degree west.The intensity error of LLJ is different for different seasons.