Study On Ice Cover Thickness Of Stability River Closed Period And Water Level Of Onset Of River Ice Breakup

Ice is a common phenomenon in the rivers of cold regions. Rivers in these regions often form the ice cover, the ice jam or the ice dam in winter, and they will bring various ice disasters. At present, forecast water level of onset of river ice breakup and ice cover thickness under natural condition is difficult. The calculation of water level of onset of river ice breakup is involving to the calculation of onset date of river ice breakup, but onset date of river ice breakup is very difficult to estimate. On the foundation of analyse the glacier epoch hydrology data through the years in Hequ segment of Yellow River , tally up a way for calculation to water level of onset of river ice breakup without the quantity key link form. Ice cover thickness have the relation with accumulation average negative air temperature of a day, Found using accumulated average negative air temperature of a day and "last factor" method ,the error of the ice thickness is greatly in last phase of the glacier epoch. Base on analyse the relation between the ice thickness and thermodynamic energy factor in Hequ segment of Yellow River,we improve the method which using accumulated average negative air temperature of a day, the problem of large error of ice thickness in last phase of the glacier epoch can be resolved .Then, built up the Multiple Index Regression model on this foundation, and forecast water level of onset of river ice breakup under natural condition. At last, improve the method which using accumulated average negative air temperature of a day and compare results of two methods with measured values. So we can draw a conclusion that the improved method can forecast thickness of ice cover more accurately.