| 摘要: |
| 利用包含三维变分同化的中尺度暴雨数值预报模式系统AREMS和AREM2.1对2003年主汛期(6~8月)进行了每天两个时次(08时和20时)的实时平行预报试验。对24 h累积降水量预报进行了分区检验,结果表明:(1)AREMS对我国夏季降水具有较强预报能力,长江中下游地区TS评分最高。长江中下游、华北和华南地区空报率大于漏报率,东北和西南地区东部则相反。(2)模式条件的改变(模式层顶、侧边界条件及初值分析)对不同区域24 h降水预报的影响程度不同:6~8月平均而言,影响最显著的是东北、华北地区,然后依次为华南、西南地区东部,影响最小的是长江中下游地区。(3)模式条件的改变对不同区域TS评分影响不同:6~8月平均而言,AREMS对东北地区降水预报效果改进最显著,特别是12~36 h时效的降水预报;对华北地区的改进也非常明显;对华南地区降水预报水平整体下降;对长江中下游和西南地区东部改进不明显。(4)模式条件的改变对不同区域空报率和漏报率影响不同:华北漏报率明显减小,但空报率有所增加;东北绝大多数的空报率与漏报率都较AREM2.1有所减小;西南东部地区,08时漏报率略有所减小,空报率增大,20时反之。(5)长江中下游、华南和西南地区东部TS评分差值在6、7、8各月变化明显。 |
| 关键词: 降水预报 客观检验 AREMS |
| DOI： |
| 分类号: |
| 基金项目:"十五"国家重点科技攻关计划项目(2001BA607B);科技部重点转面上项目"我国南方致洪暴雨预测预警系统"资助 |
|
| VERIFICATIONS OF PRECIPITATION FORECASTS FROM ADVANCED AREMS DURING 2003 FLOOD SEASON |
|
WANG Ye-hong1, ZHAO Yu-chun2, ZHANG Bing1
|
|
1.Institute of Heavy Rain, Wuhan, CMA, Wuhan 430074, China;2.Wuhan Central Meteorological Observatory, Wuhan 430074, China
|
| Abstract: |
| The real time forecasting experiments during the main flood season in 2003 are performed two times a day by two model systems,with one the mesoscale heavy rain forecasting model system named AREMS(Advanced Regional Eta-coordinate Model System) including three-dimensional variational assimilation and the other the AREM model version 2.1.The 24hr accumulated precipitation forecasts are verified in different parts of China.The results show as follows:(1) AREMS has a better forecasting ability for summer precipitation in China,with the highest Ts score in the middle-lower valleys of Yangtze River.Fault-hitting rates are bigger than no-hitting rates in the middle-lower reaches of Yangtze River,North China and South China and it is just reversal in Northeast China and the east part of Southwest China.(2) The changes of model conditions(including model level top,lateral boundary condition and initial condition) have different impacts on the 24hr forecasted precipitation in different areas,with Northeast China and North China influenced most evidently from June to August,South China and the east part of South-west China coming to the next and the middle-lower reaches of Yangtze river least impacted.(3) The changes of model conditions have different influences on Ts scores in different areas.In general,AREMS has most obviously improved precipitation forecast in Northeast China,especially for the period from 12 to 36 forecasting hours.The improvement in North China is also obvious.However,the precipitation prediction ability in South China is generally decreasing,with little improvement in the middle-lower valleys of Yangtze River and the east part of Southwest China.(4) The changes of model conditions have different effects on false-hitting rates and no-hitting rates in different areas.The latter ratios are obviously reduced in North China as opposed to false-hitting rates.Most no-hitting and false-hitting rates in Northeast China are less than those of AREM2.1.In the east part of South-west China,no-hitting rates are slightly reduced at 08h as opposed to false-hitting rates,but it is reversed at 20h.(5) There exist obvious differences of Ts scores in the middle-lower valleys of Yangtze River,South China and the east part of South-west China in June,July and August. |
| Key words: precipitation forecast objective verification AREMS |
