Supplementary information files for "Comparing threshold definition techniques for rainfall-induced landslides: A national assessment using radar rainfall"

Supplementary information files for "Comparing threshold definition techniques for rainfall-induced landslides: A national assessment using radar rainfall"AbstractTranslational landslides and debris flows are often initiated during intense or prolonged rainfall. Empirical thresholds aim to classify the rain conditions that are commonly associated with landslide occurrence and therefore improve understating of these hazards and predictive ability. Objective techniques that are used to determine these thresholds are likely to be affected by the length of the rain record used, yet this is not routinely considered. Moreover, remotely sensed spatially continuous rainfall observations are under-exploited. This study compares and evaluates the effect of rain record length on two objective threshold selection techniques in a national assessment of Scotland using weather radar data. Thresholds selected by ‘threat score’ are sensitive to rain record length whereas, in a first application to landslides, ‘optimal point’ (OP) thresholds prove relatively consistent. OP thresholds increase landslide detection and may therefore be applicable in early-warning systems. Thresholds combining 1- and 12-day antecedence variables best distinguish landslide initiation conditions and indicate that Scottish landslides may be initiated by lower rain accumulation and intensities than previously thought.

补充信息文件《比较降雨诱发滑坡的阈值定义技术：利用雷达降雨进行的国家评估》摘要：滑坡和泥石流往往在强降雨或持续性降雨期间发生。经验性阈值旨在对与滑坡发生通常相关的降雨条件进行分类，从而提升对这些灾害的理解和预测能力。用于确定这些阈值的客观技术可能会受到所使用降雨记录长度的影響，然而这一点并未得到常规考虑。此外，遥感空间连续降雨观测数据尚未得到充分挖掘。本研究通过使用天气雷达数据对苏格兰进行的国家评估，比较并评估了降雨记录长度对两种客观阈值选择技术的影响。通过‘威胁分数’选择的阈值对降雨记录长度敏感，而在首次应用于滑坡的尝试中，‘最优点’（OP）阈值显示出相对的一致性。OP阈值提高了滑坡检测率，因此可能在早期预警系统中得到应用。结合1-和12天前期变量的阈值最佳地区分滑坡启动条件，并表明苏格兰的滑坡可能由比先前所想更低的降雨累积量和强度引发。