基于高密度站网的石河子地区暴雨精细化时空分布特征

Characteristics of Refined Temporal-Spatial Distribution of Rainstorms over Shihezi Area Based on a High-Density Observing Station Network

摘要: 本文利用石河子地区历史降水数据进行数据分析，得出石河子地区暴雨强对流天气的特征：1) 强度特征：暴雨极端值主要集中在沙漠边缘、绿洲沙漠过渡带及山区，区域降水变率大、局地性强；2) 时间变化特征：暴雨频次逐年上升，近年暴雨极端性增强；3) 空间分布特征：暴雨分布呈现“纬度 + 地形”双重制约的空间聚类，将石河子地区暴雨划分为“中部春汛型”、“北部夏季极端型”、“山区高频型”、“过渡带极值型”四大区域；4) 季节与月份特征：春夏季主导，5月为核心高发区，是天山北麓“春季积雪融水 + 冷空气 + 暖湿气流”以及“夏季热力对流 + 地形抬升”双重降水机制共同作用的结果。

Abstract: This paper analyzes historical precipitation data from the Shihezi region to determine the characteristics of heavy rain and severe convective weather in this area: 1) Intensity Characteristics: Extreme rainfall values are mainly concentrated at the desert edge, the oasis-desert transition zone, and mountainous areas. The regional precipitation variability is high and highly localized. 2) Temporal Variation Characteristics: The frequency of heavy rain has shown an increasing trend year by year, with a recent enhancement in the extremity of such events. 3) Spatial Distribution Characteristics: The distribution of heavy rain exhibits spatial clustering constrained by a “latitude + topography” dual mechanism. Based on this, the heavy rain in the Shihezi region can be categorized into four distinct zones: the “Central Spring Flood Type”, the “Northern Summer Extreme Type”, the “Mountainous High-Frequency Type”, and the “Transition Zone Extreme Value Type”. 4) Seasonal and Monthly Characteristics: Precipitation is dominated by the spring and summer seasons, with May being the core high-incidence period. This is the result of a dual precipitation mechanism involving “spring snowmelt + cold air + warm moist airflow” in the northern foothills of the Tianshan Mountains, as well as “summer thermal convection + topographic uplift”.