新疆天山北坡中段河流冰凌洪水特征分析

冰凌洪水(冰洪)是新疆天山北坡中段河流冬季的一种特殊洪水,其暴发主要受气温、逆温带范围、冬季河流来水量、冰情冰厚、地势.河道弯曲率和河床条件等多种因素影响."冰洪"具有随机性、规律性和不重复性三种特性,冰凌洪水的峰型类似于暴雨洪水具有陡涨陡落的特点,峰前陡峭而落峰则相对缓一些.以四棵树河为典型流域,对冰凌洪水的成因、发展和运动规律进行研究,并发现冰凌洪水具有"水鼓冰开"现象.对四棵树河1967—2006年冰洪流量的年内、年际分布情况看,20世纪70—80年代由于冬季气候寒冷,是"冰洪"发生最多的时期;自进入20世纪90年代以来由于受全球气候变暖等因素影响,冰凌洪水呈现衰退趋势,气候变暖对冰洪影响非常大.

Analysis of Ice Jam Floods in River Basins on the North Slope of Middle Section of Tianshan Mountains, Xinjiang

Ice jam floods(ice flood) is a special winter floods of rivers in the northern slope of the Tianshan Mountains in Xinjiang,its outbreak and occurred is mainly affected by air temperature,inverse temperate rang,the water storage of winter rivers,ice thickness and ice conditions,topography,river bend of the river and conditions,and other factors.Ice flood has characteristics of randomness,regularity,and not repeatable.Hydrograph of ice jam flood peak similar to the type of storm flood with steep up-downing characteristics,before the peak is steep and some relative ease.Take Sikeshu River Basin as an example for typical ice jam floods,we studies development and movement of ice jam flood caused and found that the floods have an "ice water drum opening" phenomenon.The Sikeshu River basin is a cold winter period during the 1970s to 1980s,lead to a maximum period of ice jam flood;ice jam flood recession trends since the 1990s as global warming,and other factors,show that climate warming on ice flood affected greatly.