水灾是中国传统农业社会最主要的自然灾害之一,对于洛阳城来说,也是最大的威胁。伊洛河流域的环境特点决定了唐代洛阳水灾多由暴雨或连续性降水引发。流域诸河流暴涨泛溢,是水灾的最主要形式。今洛阳地处暖温带大陆性季风气候带,受季风影响,降水多集中在夏秋之际。唐代时期虽然气候与今稍异,但气候带的总体特征则无太大差别,降水亦多集中于夏秋,水灾也多发生在农历六月至八月。就整 Flood is one of the most important natural disasters in China’s traditional agricultural society and is also the greatest threat to Luoyang City. The environmental characteristics of Yiluo River Basin determine that floods in Luoyang during the Tang Dynasty were mostly caused by heavy rainfall or continuous precipitation. The rivers and streams of the valley have surged and overflowed, which is the most important form of flood disaster. Luoyang now is located in warm temperate continental monsoon climate zone, affected by the monsoon, precipitation is more concentrated in the summer and autumn. Although the climate in the Tang Dynasty was slightly different from the present, the general characteristics of the climate zone are not much different. Rainfall is also mostly concentrated in the summer and autumn. Floods also occurred in the lunar month from June to August. Whole