Page 211 - 《高原气象》2025年第5期

5 期 王彩霞等：海河流域洪水时空特征及致洪暴雨天气学分型 1329
Moreover， the windward areas of the Taihang Mountains and the Yan Mountains are also concentrated areas of
heavy rain， leading to sharp rises in river levels， concentrated flood volumes， high flood peaks， and short histor‐
ical durations. Therefore， extremely large floods are most likely to occur in the central and southern parts of the
basin. Furthermore， statistical analysis on the historical flood distribution and interannual variation of precipita‐
tion anomaly in the Haihe River Basin from 1952 to 2020 shows that over 80% of individual flood events and
100% of regional floods occurred in years with above-average precipitation. The inter-decadal fluctuations in the

number of historical floods exhibit a "more-less-more-less" stage-wise characteristic， which is consistent with the
characteristics of summer precipitation changes in North China. Finally， based on the analysis of the weather
chart on the day and the past 4 days of the extreme rainfall events causing floods occurrence， selected Haihe Riv‐
er Basin （111° E-121° E， 34° N-43° N） as a key area， with analyzing the influencing system and occurrence
mechanism of the heavy rain in the key area， the extreme rainfall events causing floods in the Haihe River Basin
can be roughly classified into five synoptic patterns： northward typhoon pattern， northeast cold vortex + south‐
west vortex pattern， low vortex pattern， upper-level trough pattern， and Mongolian cold vortex pattern. Among
them， the proportion of extreme rainfall events caused by typhoons in the Haihe River Basin is the highest， ac‐
counting for 42. 4%， followed by cold vortices and low vortices， accounting for 27. 3% and 15. 2% respectively.
The three regional extreme floods that occurred in the basin were also influenced by typhoons and low vortices.
Key words： flood events； temporal and spatial characteristics； synoptic patterns； Haihe River Basin； flood-
causing rainstorms