河西走廊东部结冰初、终日气候特征

利用1961-2015年河西走廊东部5个气象站点结冰初、终日观测资料和地、气温资料，采用现代气候诊断分析方法，分析了河西走廊东部结冰初、终日的时空变化特征以及结冰初、终日与地、气温的关系。结果表明：受海拔、地形地势、植被覆盖和地表岩性等影响，在空间分布上，结冰初日为山区最早，荒漠区次之，绿洲平原区最晚；结冰终日为山区最晚，荒漠区次之，绿洲平原区最早；各地结冰初、终日存在一定的异常性，正常结冰初、终日的年份概率均在60%左右，偏早和特早结冰初日以及偏晚和特晚结冰终日的年份概率均在20%左右，结冰初、终日与气温的异常年份有较好的对应关系。在时间变化上，结冰初日呈推迟趋势，结冰终日呈提早趋势，结冰初日推迟的幅度比结冰终日提早的幅度更大；结冰初、终日时间序列均分别存在10~12 a、8~10 a的准周期变化。结冰初、终日与地、气温和海拔具有极显著相关性，地、气温每升高1℃，结冰初日分别推迟约3.0 d、3.5 d，结冰终日分别提早约4.2 d、4.9 d；海拔每升高100 m，结冰初日提早约1.8 d，结冰终日推迟约2.5 d；结冰终日对气候变暖和海拔变化的响应程度比结冰初日更敏感。

Climate characteristics of the initial ice date and end ice date in east of the Hexi Corridor

Using initial ice date and end ice date, as well as soil and air temperature data, from five meteorological stations in east of the Hexi Corridor during 1961-2015, temporal and spatial change characteristics of initial ice date and end ice date and their relation to soil, air temperatures and altitude were analyzed in this paper with modern climate diagnosis method. The results showed that, temporally, the initial ice date was earlier in mountains, followed by desert, finally in oasis and plain, and the end ice date was later in mountains, followed by desert, finally in oasis and plain, because of the influence of altitude, topography, vegetation and surface lithology. Initial ice date and end ice date had certain abnormal locally, with the probability of about 60% of normal initial ice date and end ice date. Probability of partial early year and early year of initial ice date and probability of partial late and late year of end ice date, which will cause hazard to production, were about 20%. There was a good correspondence between initial ice date and end ice date and the year with abnormal temperature. The initial ice date tended to delay and the end ice date tended to get early, the delayed magnitude was more than the early magnitude. Time series of initial ice date and end ice date had ten to twelve years and eight to ten years quasi-periodic variation, respectively. There were extremely significant correlations between initial ice date and end ice date and soil and air temperatures and altitude. The initial ice date will delay about 3.0 d and 3.5 d and the end ice date will about 4.2 d and 4.9 d ahead of time for 1 degree centigrade increase of soil and air temperature; the initial ice date will 1.8 d ahead of time and the end ice date will delay 2.5 d for every 100-m altitude increase. The end ice date was more sensitive response to climate warming and altitude increasing than the initial ice date.