摘要
在极端降水事件不断增多和增强的背景下,研究小尺度区域的极端降水时空格局变化,有利于区域整体性评估异常降水带来的风险。基于百色地区12个气象站点57年逐日降水资料,通过选取9个极端降水指数,使用Mann-Kendall趋势检验和ArcGIS反距离插值,从持续性指数、绝对指数、阈值指数和强度指数等方面分析了百色地区极端降水的时空节律变化特征。结果表明:1961—2017年百色地区极端降水年尺度整体呈微弱增加趋势,R50,RX1 day,R95p,SDII和CDD 5个指数年尺度均表现出增加趋势,其他指数微弱下降。说明百色地区弱降水减少,而强降水在增多,干旱日数也在增加,使得降水强烈和集中,更趋于极端化。极端降水年尺度空间差异明显,而且所有指数空间分析结果均以凌云县为极大值中心,大体呈现出东南地区以上升趋势为主,西北地区以下降趋势为主的格局,可能与该地区特殊地形因素有关。降水高频区主要位于有地形抬升、大气辐合上升的山脉周围。研究结果可为百色地区水资源规划和灾害风险管理提供借鉴和支撑,以期降低极端灾害风险。
In the context of increasing and intensifying extreme precipitation events, the study of the changes in the spatial and temporal patterns of extreme precipitation in small-scale regions is conducive to the overall regional assessment of the risks brought by abnormal precipitation. Based on daily precipitation data of from 12 general meteorological stations in Baise area in 57 years, we selected 9 extreme precipitation indexes, and used Mann-Kendall trend test and ArcGIS inverse distance interpolation to analyze the characteristics of spatiotemporal changes of extreme precipitation in Baise area from the aspects of sustainability index, absolute index, threshold index and intensity index. The results show that: from 1961 to 2017, the annual scale of extreme precipitation in Baise area as a whole showed a slight increase trend, the R50, RX1 day, R95 p, SDII and CDD at annual scale all showed the increasing trend, other indexes fell slightly. Which indicated that the weak precipitation was decreasing and the heavy precipitation was increasing in Baise area, the number of dry days was also increasing, the precipitation tended to be intense and concentrated, precipitation tended to be extreme;the spatial difference of extreme precipitation at annual scale was obvious, and all the exponential spatial analysis results took Lingyun County as the maximum center, showing a pattern that the southeast region was dominated by an upward trend and the northwest region by a downward trend, which might be related to the special topographic factors in this region;the high frequency area of precipitation was mainly located around mountain ranges with topographic uplift and atmospheric convergence. These results can provide reference and support for water resources planning and disaster risk management in Baise area in order to reduce the impact of extreme disaster risk.
作者
卢芹芹
秦年秀
汪军能
黄嘉丽
韦玉芳
张华玉
LU Qinqin;QIN Nianxiu;WANG Junneng;HUANG Jiali;WEI Yufang;ZHANG Huayu(College of Geographic Sciences and Planning,Nanning Normal University,Nanning 530001,China;Key Laboratory of Beibu Gulf Environment Change and Resources Use,Ministry of Education,Nanning 530001,China;Binyang Middle School,Binyang,Guangxi 530400,China)
出处
《水土保持研究》
CSCD
北大核心
2021年第3期216-222,共7页
Research of Soil and Water Conservation
基金
国家自然科学基金“变化环境下西南地区极端干旱天气的形成及应对”(41461007)。
关键词
百色地区
极端降水事件
时空节律变化特征
降水指标
Baise area
extreme precipitation event
characteristics of time-space rhythm changes
precipitation index