海河流域雨季气候特征及监测分析

论文采用日降水量和NCEP/NCAR(美国国家环境预报中心/美国国家大气研究中心)再分析环流资料,针对华北(海河流域)雨季监测困难问题,通过对比分析和合理性分析,建立了基于连续气象变量的海河流域雨季监测比湿副高法(简称QSH),并分析了海河流域雨季变化,以期改进该区域雨季监测技术。主要结论为：① 采用比湿副高法QSH监测华北(海河流域)雨季是合理的,在业务应用上具有很好的操作性;② 海河流域雨季平均的开始日期为7月9日,结束日期为8月19日,雨季长度41 d;③ 1961—2019年间海河流域雨季综合强度指数、雨季长度、雨季累计降水量长期变化不存在明显减小、缩短、增加或增大、延长、减少的趋势,但存在明显的年代际变化特征。海河流域雨季每18 a左右有一次强弱周期变化,近年处于较弱时期。

Climatic characteristics and monitoring analysis of rainy season in the Haihe River Basin

Based on the daily precipitation and NCEP/NCAR reanalysis circulation data provided by the NOAA/OAR/ESRL Physical Sciences Laboratory, and in view of the difficulties of rainy season monitoring in North China (the Haihe River Basin), this study established a specific humidity subtropical high method (QSH) for monitoring rainy season in the Haihe River Basin based on continuous meteorological variables and through contrast analysis and reasonableness analysis, and the variation of rainy season in the Haihe River Basin was analyzed. The main conclusions are as follows: 1) It is reasonable to monitor the rainy season in the Haihe River Basin by using the specific humidity-subtropical high method, which has good operability in practice. 2) The average start date of rainy season in the Haihe River Basin is 9 July, the end date is 19 August, and the length of rainy season is 41 days. 3) There was no obvious trend of long-term change of comprehensive intensity index, length of rainy season, and accumulated precipitation of rainy season in the Haihe River Basin during 1961-2019. However, there were obvious interdecadal variations, that is, the rainy season in the Haihe River Basin has a strong or weak periodic change every 18 years, which is in a weak period in recent years.