PDF(Pubmed)
Abstract：
Effective risk management requires accurate assessment of population exposure to volcanic hazards. Assessment of this exposure at the large-scale has often relied on circular footprints of various sizes around a volcano to simplify challenges associated with estimating the directionality and distribution of the intensity of volcanic hazards. However, to date, exposure values obtained from circular footprints have never been compared with modelled hazard footprints. Here, we compare hazard and population exposure estimates calculated from concentric radii of 10, 30 and 100 km with those calculated from the simulation of dome- and column-collapse pyroclastic density currents (PDCs), large clasts, and tephra fall across Volcanic Explosivity Index (VEI) 3, 4 and 5 scenarios for 40 volcanoes in Indonesia and the Philippines. We found that a 10 km radius-considered by previous studies to capture hazard footprints and populations exposed for VEI ≤ 3 eruptions-generally overestimates the extent for most simulated hazards, except for column collapse PDCs. A 30 km radius - considered representative of life-threatening VEI ≤ 4 hazards-overestimates the extent of PDCs and large clasts but underestimates the extent of tephra fall. A 100 km radius encapsulates most simulated life-threatening hazards, although there are exceptions for certain combinations of scenario, source parameters, and volcano. In general, we observed a positive correlation between radii- and model-derived population exposure estimates in southeast Asia for all hazards except dome collapse PDC, which is very dependent upon topography. This study shows, for the first time, how and why concentric radii under- or over-estimate hazard extent and population exposure, providing a benchmark for interpreting radii-derived hazard and exposure estimates.
UNASSIGNED: The online version contains supplementary material available at 10.1007/s00445-023-01686-5.
UNASSIGNED: The online version contains supplementary material available at 10.1007/s00445-023-01686-5.
摘要：
有效的风险管理需要对人口暴露于火山灾害的准确评估。大规模评估这种暴露通常依赖于火山周围各种大小的圆形足迹，以简化与估计火山危害强度的方向性和分布相关的挑战。然而,到目前为止,从未将从圆形足迹获得的暴露值与建模的危险足迹进行比较。这里,我们比较了从10、30和100km的同心半径计算出的危险和人口暴露估计值，以及从峰值和柱塌陷火山碎屑密度电流（PDC）模拟计算出的估计值，巨大的碎屑,在印度尼西亚和菲律宾的40座火山中，tephra的火山爆炸指数（VEI）为3、4和5种情景。我们发现，以前的研究认为10公里半径可以捕获VEI≤3次喷发暴露的危险足迹和种群，通常会高估大多数模拟危险的程度，除了柱塌陷PDC。半径30公里-被认为是威胁生命的VEI≤4种危险的代表-高估了PDC和大碎屑的范围，但低估了tephra坠落的程度。100公里的半径包含了大多数威胁生命的模拟危险，尽管某些场景组合也有例外，源参数，和火山。总的来说,我们观察到，除了圆顶塌陷PDC外，东南亚所有危害的辐射和模型得出的人口暴露估计值之间存在正相关关系，这非常依赖于地形。这项研究表明,第一次,同心半径如何以及为什么低估或高估危险程度和人口暴露，为解释半径衍生的危险和暴露估计提供基准。
■在线版本包含补充材料，可在10.1007/s00445-023-01686-5获得。
■在线版本包含补充材料，可在10.1007/s00445-023-01686-5获得。
