气候变化中山洪暴发的时空聚类（中国，1950-2015年）
Space-time clustering of flash floods in a changing climate (China, 1950-2015)
摘要：
暴洪灾害-造成经济或生命损失或两者兼有的暴洪-在空间和时间上的持续性是对遭受水文风险的地区的一种诊断措施。持续性的概念可以通过聚类分析进行评估，在这里进行的分析，在中国发生在1950-2015年期间的山洪灾害的国家清单。具体来说，我们调查的时空格局分布的山洪和他们的聚类行为，通过使用全球和本地的方法：第一，基于Ripley的K-函数，第二扫描统计。因此，我们可以可视化聚集事件的模式，估计集群持续时间，并假设它们随时间的演变，也与降水趋势。由于数据集的空间（整个中国领土）和时间尺度（66年）很大，我们能够捕捉到某些集群是否在特定的位置和时间聚集，以及它们的大小是否倾向于增加或减少。总体而言，中国东部地区比全国其他地区更容易遭受山洪暴发。探测到的集群显示，这些现象主要发生在7月至10月，这一时期与中国的雨季相吻合。检测到的集群的数量随着时间的推移而增加，但在最近的一段时间内，相关的持续时间急剧减少。这可能表明触发机制发生了变化，而触发机制是短时间极端降雨事件的典型特征。最后，由于山洪与降水及其极端实现直接相关，我们间接评估了触发因素本身的大小是否也随时间和空间而变化，从而能够在气候变化的背景下进行考虑。
英文摘要：
The persistence over space and time of flash flood disasters -- flash floods that have caused either economical or life losses, or both -- is a diagnostic measure of areas subjected to hydrological risk. The concept of persistence can be assessed via clustering analyses, performed here to analyse the national inventory of flash floods disasters in China occurred in the period 1950-2015. Specifically, we investigated the spatio-temporal pattern distribution of the flash floods and their clustering behavior by using both global and local methods: the first, based on the Ripley's K-function, and the second on scan statistics. As a result, we could visualize patterns of aggregated events, estimate the cluster duration and make assumptions about their evolution over time, also with respect precipitations trend. Due to the large spatial (the whole Chinese territory) and temporal scale of the dataset (66 years), we were able to capture whether certain clusters gather in specific locations and times, but also whether their magnitude tends to increase or decrease. Overall, the eastern regions in China are much more subjected to flash floods compared to the rest of the country. Detected clusters revealed that these phenomena predominantly occur between July and October, a period coinciding with the wet season in China. The number of detected clusters increases with time, but the associated duration drastically decreases in the recent period. This may indicate a change towards triggering mechanisms which are typical of short-duration extreme rainfall events. Finally, being flash floods directly linked to precipitation and their extreme realization, we indirectly assessed whether the magnitude of the trigger itself has also varied through space and time, enabling considerations in the context of climatic changes.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
