Before revision:  Koch (2017, 2018) introduced a concept of spatial risk measure and a related set of axioms which are well-suited to analyse and quantify the risk due to events having a spatial extent, precisely such as natural disasters.
After revision:  Koch (2017, 2018) introduced a concept of spatial risk measure and a related set of axioms introduced by Koch (2017, 2019), we quantify the risk due to events having a spatial extent, precisely such as natural disasters.