1981—2020年位山灌区旱涝急转识别与趋势预测

Identification and Trend Prediction of Abrupt Drought-flood Transition in Weishan Irrigation District during 1981—2020

摘要:

基于山东省聊城市位山灌区40年月降雨量数据,利用长/短周期旱涝急转指数(LDFAI/SDFAI)对位山灌区6—9月的旱涝急转事件进行识别。利用趋势线法、移动平均法、M-K趋势检验和R/S分析法对旱涝急转的时间变化趋势以及强度变化趋势进行分析。结果表明:位山灌区6—9月长周期共发生过15次旱涝急转事件;短周期6—7月全是“旱转涝”事件,7—8月旱涝急转无明显规律,8—9月以“涝转旱”事件为主。未来LDFAI强度整体呈下降趋势,6—7月SDFAI强度呈现上升趋势,7—8月SDFAI强度呈上升趋势,8—9月SDFAI强度呈下降趋势,但各强度趋势显著性均不高。

Abstract:

Based on the 40-year monthly rainfall data of Weishan Irrigation District in Liaocheng Municipality, Shandong Province, the long/short duration drought-flood abrupt transition indices (LDFAI/SDFAI) were adopted to identify abrupt drought-flood transition events from June to September. Trend line method, moving average method, Mann-Kendall (M-K) trend test and R/S analysis were used to analyze the temporal variation and intensity trends of such events. The results show that a total of 15 long-duration abrupt drought-flood transition events occurred from June to September in the study period. For short-duration events, all cases from June to July were drought-to-flood transitions; no obvious regularity was found for events from July to August, while flood-to-drought transitions dominated from August to September. In the future, the overall intensity of LDFAI will present a downward trend. The intensity of SDFAI shows an upward trend from June to July and July to August, and a downward trend from August to September. None of the above trends are statistically significant.