基于EOF的陕西果区近50年降水分布特征研究

Study on Spatial and Temporal Distribution Characteristics of Precipitation in Nearly 50 Years by Using Empirical Orthogonal Function in Shaanxi Fruit District

为了研究陕西果区降水时空分布特征,利用1961—2010年共50年的29个果业县气象站的降水资料,采用EOF(经验正交函数)展开和趋势法,分析了陕西省果区近50年年降水的时空分布特征。结果表明,陕西省果区年降水呈波动式减少趋势,气候倾向率为-18.5 mm/10 a;空间场分为总体一致型和南-北反相型,其中总体一致型为主要的空间形式。各空间型的时间系数波动强烈,体现了陕西果区降水年际震荡较大。

In order to study the spatial and temporal distribution of precipitation characteristics of Shaanxi fruit district, the temporal and spatial distribution characteristics of precipitation in nearly 50 years of Shaanxi fruit district was analyzed by using EOF （empirical orthogonal function） distribution and trend method, based on precipitation data of nearly 50 years from 1961 to 2010 at 29 weather stations in Shaanxi fruit district. The results showed that： the precipitation of Shaanxi fruit district presented a fluctuation decreasing trend, and the climate tendency rate was-18.5 mm/10 a; the space field was divided into the overall consistency and the south-north inverting type, and the generally consistent type was the main form of it. The space-time coefficient fluctuates strongly, which indicated that the precipitation of Shaanxi fruit district showed a large interannual concussion.