| 顾伟宗,陈丽娟,张培群,李维京,李想,刘绿柳. 2009. 基于月动力延伸预报最优信息的中国降水降尺度预测模型[J]. 气象学报, 67(2):280-287, doi:10.11676/qxxb2009.028 |
| 基于月动力延伸预报最优信息的中国降水降尺度预测模型 |
| Downscaling precipitation prediction in China based on Optimization Information Extracted from Monthly Dynamic Extended Range Forecast. |
| 投稿时间：2007-09-04 修订日期：2007-11-07 |
| DOI：10.11676/qxxb2009.028 |
| 中文关键词: 月动力延伸预报, 最优信息, 降水, 降尺度预测 |
| 英文关键词:Dynamic extended range forecast, Optimization information, Precipitation, Downscaling |
| 基金项目:国家自然科学基金项目(40675039)、国家科技部科技支撑计划项目(2006BAC02B04)和中国气象局业务建设项目（气候模式产品在区域气候预测业务中的应用） |
|
| 摘要点击次数: 3944 |
| 全文下载次数: 3072 |
| 中文摘要: |
| 利用国家气候中心月动力延伸预报结果、NCEP/NCAR再分析资料和中国160个站观测资料，通过计算两次相关的方法，获取最优预报信息作为建立降尺度预测模型的预测因子，提取的最优预测因子同时满足既是观测环流要素场影响降水的关键区域，又是模式要素场预报的高技巧区域两个条件。结合挑选出的最优预测因子，利用最优子集回归建立月平均降水的降尺度预测模型。文中设计了消除预测因子和预测量的线性趋势值后建立预测模型（方案1）和直接利用原始资料建立预测模型（方案2）两种方案。经过独立样本检验，发现这两种方案建立的预测模型都能够提高月尺度降水预测，方案1对月尺度降水预测的距平相关系数平均可达0.35。利用该方案对超前时间分别为0、5、10 d的月动力延伸预报产品进行月降水的降尺度预测表明，模式初值信息不仅影响月动力延伸预报结果，也影响降尺度应用效果，利用超前时间为0和5 d的月动力延伸预报结果进行降水降尺度预测可在业务中参考。此外，降尺度预测模型中选取的预测因子不仅在统计上是显著的，同时也具有清楚的物理意义。 |
| 英文摘要: |
| Using monthly dynamic extended range forecast (DERF) products, NCEP/NCAR reanalysis data and 160 station data in China, we have extracted optimal predictors which significantly influence precipitation. The predictors are selected from high skill regions of DERF and high correlation between observing precipitation and other variables. Downscaling monthly anomaly precipitation are predicted using the optimal subset regression from selected predictors. Two schemes are designed in the paper. One uses the detrending data to establish the prediction equations (scheme 1), the other uses the original data to establish the prediction equations (scheme 2). The results show that the two schemes can improve the skills of monthly precipitation forecast whereas scheme 1 has higher skills than scheme 2. The anomaly correlation coefficient between scheme 1 and observation can reach 0.35. Downscaling tests indicate that initial fields could have great influence on model results and downscaling precipitation prediction. Using scheme 1 and DERF results from different leadtime including 0 day, 5 days and 10 days, it shows that when lead time is 5 days and 0 day, the downscaling precipitation prediction could be used as a good reference in monthly climate prediction. In the downscaling model, selected predictors can pass statistic tests and have clear physical meanings. The downscaling methods can be applied in operational climate prediction. |
|
HTML 查看全文
查看/发表评论 下载PDF阅读器 |