Improving Disaster Preparedness and Response by Considering Time-Dependency of Human Exposure in Crisis Modeling

Vulnerability describing the status of a society with respect to an imposed hazard or potential impact is considered a strongly multidisciplinary concept. A central objective of vulnerability assessment is to provide indications where and how people - and more specifically, what kind of people - might be affected by a certain impact. For assessment of the social dimension of vulnerability, population exposure mapping is usually considered the starting point. Integration of social structure and varying aspects of resilience further differentiate situation-specific vulnerability patterns on a local scale. Particularly in metropolitan areas, the spatial distribution of population is highly time-dependent due to human activities and mobility. Identifying distinct day- and nighttime population distribution characteristics is a major improvement compared to standard residence-based models, but does however only display part of reality. New technologies and data processing capabilities allow moving into the field of realtime analysis and representation of human movement. The vulnerability of each relevant element at risk, including human beings and society in general and its time-dependent variation is characterized both by its pre-event status and by its possible evolution during a crisis. In this study we present several approaches using multi-level geospatial information for spatio-temporal modeling of human exposure. For general population distribution patterns including variation over the diurnal cycle we applied census-based spatial disaggregation methods additionally considering commuting and working statistics. Referring to cell phone user activity mapping and voluntarily-provided locationspecific information in social networks we give an outlook to future options of near-real-time information retrieval during actual crisis events.