山东夏季及夏季各月降水的时空分布特征

Spatial and Temporal Distributions of Precipitation in Summer and Each Month in Shandong Province

旱涝是山东的主要气象灾害之一,为了研究山东的旱涝特征特别是夏季的降水规律,统计了山东省26个气象站1961—2010年共50年的夏季降水资料,以降水量距平百分率为主要指标衡量夏季降水的年际变化,并用谱分析的方法对其进行分析,得到了山东夏季及夏季各月降水的总体趋势、周期特征和空间分布特征。在此基础上,对夏季旱涝年进行了划分,并用标准差的空间分布进一步分析了夏季降水的年际变化。结果表明：山东夏季及夏季各月降水都具有2.1~3.3年左右的短周期和10年左右的长周期;从降水趋势来看,7月和夏季都呈减少的趋势,7月减少的趋势最明显,而6月和8月则呈略微增加的趋势;山东夏季和夏季各月降水的空间分布极为不均,具有明显的地域性特征;夏季旱年和涝年分别为7年和5年。通过研究发现,山东夏季和夏季各月降水的时间和空间分布都极为不均,因此认识其特征是非常有必要和有意义的。

Drought and flood are the main weather disasters in Shandong. In order to research the characteristics of rainfall, especially during the season of summer, the author made statistics of the summer rainfall information from 1961 to 2010 among the 26 weather stations in Shandong. The annual diversification was measured with the main index of anomaly percentage of rainfall and analyzed with the way of spectral analysis. So the general trend of monthly rainfall in summer of Shandong was obtained through the data, as well as the periodical and the spatial characteristics. On the basis above, the years of drought and flood in summer were also measured and the annual diversification of summer rainfall was further analyzed with the method of spatial distribution of standard deviation. The results showed that： the summer and summer monthly rainfall in Shandong both had short cycle time of 2.1-3.3 years and long cycle time of about 10 years. It also showed decreasing trend of rainfall in July and the whole summer, especially in July; meanwhile increasing trend in June and August. The spatial distribution was uneven and had distinct geographical features. The dry years and wet years in summer were 7 and 5 respectively. Through this research, it was known that both the spatial and temporal distribution of summer and summer monthly rainfall in Shandong were extremely uneven, so it was very significant and necessary to learn about its characteristics.