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黄河干流长5464公里,流经青海、四川、甘肃、宁夏、内蒙、陕西、山西、河南、山东9个省区,流域面积75.2万平方公里,是我国第二条大河。黄河不仅以多沙著称,冰凌患害也同样闻名于世。黄河冰患是因凌汛期流冰结坝壅水造成的,主要发生在自西南流向东北的宁蒙段和河南、山东段。由于这两段纬度相差3～4度以上,致使气温上暖下冷,流凌封冻由下游段溯源而上,而解冻开河则由上而下。加之河道特性影响,黄河下游河道上宽下窄,黄河上游的宁蒙段坡缓多岔,使流冰排泄不畅,在陡湾、浅滩、狭窄段流冰受阻。上游段解冻后,河槽蓄水量、消冰水量等汇流,使流量逐段增多,形成明显的洪峰,而下游段气温低,冰盖尚未充分解体消融,洪峰过境水鼓冰裂,水流的动力作用,使流冰块部分下潜而卡冰结坝,使水位急剧抬升而造成凌汛灾害。
The Yellow River is 5464 kilometers long and flows through 9 provinces and autonomous regions including Qinghai, Sichuan, Gansu, Ningxia, Inner Mongolia, Shaanxi, Shanxi, Henan and Shandong. The drainage area is 752,000 square kilometers and is the second largest river in China. The Yellow River is famous not only for sandy, ice damage is equally famous in the world. The ice in the Yellow River is caused by the slump-flow ice-dam barrage in the flood season, mainly occurring in the Ningmeng section flowing to the northeast from the southwest and the sections of Henan and Shandong. As the two latitudes differ by more than 3-4 degrees, causing the temperature to warm and cool, flowing Ling frozen from the lower reaches of the traceability, and thawed by the river from top to bottom. Coupled with the impact of river characteristics, the upper and lower reaches of the Yellow River are wider and narrower, and the upper reaches of the Yellow River are slightly dull and slippery, resulting in sluggish flow of ice and obstruction of flow ice in steep bays, shoals and narrow sections. After the thawing of the upper reaches, the confluence of water storage in the river channel and deicing water will increase the flow rate gradually and form a distinct flood peak. However, the temperature in the lower reaches is low, the ice sheet has not yet been fully dissolved and dissolved, The role of the flow of ice to dive part of the ice card dam, so that the water level rise dramatically and cause flood disaster.