摘要
确定泥石流激发雨量阈值以及建立有效的预警预报等级是泥石流防灾减灾的重要手段之一。就2008—2013年汶川灾区群发性、局部地区暴发的泥石流雨量过程进行分析,分别得到北川、清平、都江堰、映秀4个地区泥石流暴发的"雨强-历时"阈值。其中,都江堰地区阈值较高,映秀最低;北川地区群发性泥石流阈值较局部地区要高,而其他3个地区不明显,部分地区群发性泥石流I-D值还低于局部地区泥石流I-D值。根据群发性和局部区域泥石流暴发的雨强-历时、前期降雨+实时降雨关系,初步建立了以上4个地区的预警预报等级,以期能为该区泥石流预警预报提供参考。
Establishing precise rainfall threshold and effective forecasting system is one of the important measures to prevent debris flow disasters and reduce damage. We analyzed the rainfalls triggered by debris flows at clustering and small scales in the Wenchuan earthquake region of southwestern China during the period of 2008—2013,aiming to establish the range of rainfall intensity-duration threshold in Beichuan,Qingping,Dujiangyan and Yingxiu of Sichuan Province. The rainfall threshold in Dujiangyan was higher while that in Yingxiu was lower than in the other two regions. The threshold of critical rainfalls of clustering debris flows in Beichuan was higher than that of small-scale debris flows,but this trend could not be found in the other three regions. There was an obvious dividing line of rainfall intensityduration between clustering and small-scale debris flows in the other three regions. Furthermore,the rainfall intensity-duration of small-scale debris flows in some regions was higher than that of clustering events. Finally,the warning and forecasting grades of debris flows were developed for the four regions based on the relationships between rainfall intensity-duration,and antecedent rainfall and real-time rainfall,which would be helpful for warning and forecasting of local debris flows.
出处
《北京林业大学学报》
CAS
CSCD
北大核心
2015年第9期37-44,共8页
Journal of Beijing Forestry University
基金
“十二五”国家科技支撑计划课题((2012BAK10B04)
北京林业大学新进教师科研启动项目(BLX2014-12)
关键词
群发性泥石流
预警预报
汶川地震
雨量阈值
clustering debris flows
warning and forecasting
Wenchuan earthquake
rainfall threshold