北斗CORS探测的大气可降水量与重庆降雨的关系

通过分析2018年2次典型降雨过程中大气可降水量(precipitable water vapor,PWV)的分布特征及其与实际降水量的关系,探讨PWV在预测降雨中的应用。结果表明,在降雨过程中,PWV的分布与实际降水量具有很好的相关性。PWV对降雨的发生具有一定的指示作用,在降雨发生前6~12 h,PWV开始增加;在降雨发生前1~2 h内PWV迅速上升;当PWV显著增加并保持高值时,预示强降雨的发生。PWV变化越快,降雨概率和降水量就越大。滑动平均处理结果进一步证明,强降雨发生前后,PWV会出现快速聚集和释放的现象,PWV可作为短期临近预报及天气分析等研究和应用的序列资料,为传统气象手段提供有力补充。

Relations between Precipitable Water Vapor Measured by Beidou CORS and Chongqing Precipitation Processes

We discuss the distribution characteristics of precipitable water vapor(PWV) and the relationship between PWV and actual precipitation during two typical precipitation processes in 2018 to analyze the application of PWV in rainfall prediction. The results show that during the precipitation process, PWV distribution is consistent with actual precipitation. PWV presents indications about rainfall prediction; PWV starts to increase within 6 to 12 hours before rainfall occurs, and rises rapidly within 1 to 2 hours before precipitation occurs. When PWV increases significantly and maintains a high value, it indicates that heavy precipitation will occur. Moreover, the faster PWV changes, the greater precipitation probability and amount of precipitation. Through the sliding average treatment, the phenomenon of rapid accumulation and release of PWV before and after heavy rainfall occurrence is further proven. PWV can be used as sequence data for research and application of short-term nowcasting and weather analysis. It also provides a powerful supplement for traditional meteorological methods.