最近50年来山东地区夏季降水的时空变化及其影响因素研究

Spatial-temporal Variations and Influential Factors of Summer Precipitation in Shandong Region During the Last 50 Years

利用山东地区16个气象站1961～2012年逐月降水资料以及同期大气环流指数资料，采用Mann．Kendall非参数检验法、累积距平法、有序聚类分析法以及Mann．Whitney．Pettitt（MWP）法等方法，对最近50a来山东地区夏季降水及其占全年降水比例的时空变化及影响因素进行了研究。结果表明，最近50a来，山东地区夏季降水呈现总体下降趋势，但有显著的阶段性。其中，沿海地区变化幅度小于内陆，其阶段转换和突变也早于内陆，内陆中山区又早于平原。沿海地区夏季降水占年降水比例呈现总体上升趋势，但无明显的阶段性和突变现象；而内陆地区呈现总体下降趋势，但存在阶段性和突变现象，其中山地与平原问又有差异。分析表明，山东地区夏季降水变化与同期东亚夏季风、南方涛动和北极涛动之间有显著的响应关系，但在沿海与内陆、山地与平原之间存在差异。

Shandong region is located in eastern coastal of China. Due to the combined effects of marine and Continental, monsoon climate significantly, rainfall mainly concentrate in the summer and heavy rain often appears. It is easy to form flood disaster. Because of less rain in the other seasons, especially spring, it is easy to form the drought. Due to unequal distribution of rainfall during the year, the drought and flood disas- ters occurred frequently in the region. Studying the characteristics of summer precipitation from regional scale in Shandong region, not only has the vital significance to the evaluation of regional precipitation and the water resources situation, also provides the scientific basis for the prediction of precipitation in the fu- ture and the change trend of water environment and water resources. Based on the monthly precipitation da- ta of 16 weather stations in Shandong region in 1961-2012 and atmospheric circulation index included The East Asian summer monsoon （EASM） index, Southern Oscillation （SO）Index and Arctic Oscillation （AO） Index. The non-parametric Mann-Kendall Test, Accumulated Difference Curve, Order Cluster Analysis and Mann-Whitney-Pettitt （MWP） methods were used in this paper to reveal the temporal-spatial variation and influential factors of summer precipitation and summer precipitation accounted for the proportion of annual precipitation in Shandong region during the last 50 years. Results obtained showed a number of observa- tions： The summer precipitation showed a decreasing trend on the whole during the last 50 years. But the change process had obvious stages. The coast is less than the inland in the changes amplitude of summer pre- cipitation. The coast is earlier than the inland in the stages transformation and mutation of the summer pre- cipitation, mountains earlier than plains in the inland. The summer precipitation accounted for the propor- tion of annual precipitation showed an increasing trend on the whole in the coast. But the change process had no obvious stages and mutation phenomenon. However, the summer precipitation accounted for the pro- portion of annual precipitation showed a decreasing trend on the whole in the inland. But the change process had stages and mutation phenomenon, which are different in the mountains and the plains. According to the analysis, the summer precipitation changes in Shandong region has a significant response relationship with the East Asian summer monsoon, Southern Oscillation and the Arctic Oscillation change on the same peri- od. The differences between coastal and inland, mountains and plains are notable.