Rainfall thresholds for shallow landslide occurrence in Calabria, southern Italy
Rainfall thresholds for shallow landslide occurrence in Calabria, southern Italy
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DOI：
10.5194/nhess-14-317-2014
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发表时间：
2013-09
影响因子：
4.6
通讯作者：
C. Vennari;S. L. Gariano;L. Antronico;M. Brunetti;G. Iovine;S. Peruccacci;O. Terranova;F. Guzzetti
中科院分区：
文献类型：
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作者：
C. Vennari;S. L. Gariano;L. Antronico;M. Brunetti;G. Iovine;S. Peruccacci;O. Terranova;F. Guzzetti
抽象的。在许多地区，降雨是引发山体滑坡的主要因素。确定滑坡发生的降雨条件很重要，可能有助于挽救生命和财产。在一个长期的国家项目定义降雨阈值可能发生在意大利滑坡，我们编制了一个目录的186个降雨事件，导致251个浅层滑坡在卡拉布里亚，南部意大利，从1996年1月至2011年9月。使用Google Earth®对滑坡进行地理定位，并提供地图和时间精度。我们使用的滑坡信息，并从两个互补的雨量计网络，以确定累积事件与降雨持续时间（艾德）阈值卡拉布里亚每小时的降雨量测量。为此，我们采用了现有的方法来准备降雨阈值，并估计其相关的不确定性在意大利中部。卡拉布里亚的区域阈值被认为是几乎相同的卡拉布里亚使用一套减少滑坡信息获得以前的ED阈值，略高于艾德阈值为意大利中部。我们将卡拉布里亚的滑坡降雨事件区域目录划分为岩性、土壤区域、降雨区和季节性。每个分区的事件数量不足以确定可靠的阈值，但可以对卡拉布里亚浅层滑坡的降雨条件中环境因素的作用得出初步结论。我们进一步分割区域目录的基础上，用于水文气象监测和业务洪水预报的行政区划，我们确定单独的艾德阈值的第勒尼安和爱奥尼亚海岸的卡拉布里亚。我们希望卡拉布里亚的艾德降雨阈值将用于区域和国家滑坡预警系统。这些阈值还可用于研究区域和地中海地区类似自然地理区域的滑坡灾害和风险评估，以及侵蚀和地貌演变研究。
Abstract. In many areas, rainfall is the primary trigger of landslides. Determining the rainfall conditions responsible for landslide occurrence is important, and may contribute to saving lives and properties. In a long-term national project for the definition of rainfall thresholds for possible landslide occurrence in Italy, we compiled a catalogue of 186 rainfall events that resulted in 251 shallow landslides in Calabria, southern Italy, from January 1996 to September 2011. Landslides were located geographically using Google Earth®, and were given a mapping and a temporal accuracy. We used the landslide information, and sub-hourly rainfall measurements obtained from two complementary networks of rain gauges, to determine cumulated event vs. rainfall duration (ED) thresholds for Calabria. For this purpose, we adopted an existing method used to prepare rainfall thresholds and to estimate their associated uncertainties in central Italy. The regional thresholds for Calabria were found to be nearly identical to previous ED thresholds for Calabria obtained using a reduced set of landslide information, and slightly higher than the ED thresholds obtained for central Italy. We segmented the regional catalogue of rainfall events with landslides in Calabria into lithology, soil regions, rainfall zones, and seasonal periods. The number of events in each subdivision was insufficient to determine reliable thresholds, but allowed for preliminary conclusions about the role of the environmental factors in the rainfall conditions responsible for shallow landslides in Calabria. We further segmented the regional catalogue based on administrative subdivisions used for hydro-meteorological monitoring and operational flood forecasting, and we determined separate ED thresholds for the Tyrrhenian and the Ionian coasts of Calabria. We expect the ED rainfall thresholds for Calabria to be used in regional and national landslide warning systems. The thresholds can also be used for landslide hazard and risk assessments, and for erosion and landscape evolution studies, in the study area and in similar physiographic regions in the Mediterranean area.