Evacuation simulation modelling in the event of a Near Earth Object impact

• Main Author: Nørlund, Charlotte Camilla Flindt
• Other Authors: Lewis, Hugh
• Published: University of Southampton 2013
• Subjects: 523.4
• Online Access: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.720126

Near-Earth Objects (NEOs), a group of small interplanetary objects whose orbits around the Sun approach the Earth's orbit to within 45 million km (~0.3 Astronomical Units), have the possibility to impact with the Earth. Such a hazard could potentially cause major damage and result in many casualties depending on impact location and impactor composition and energy. Unique to this type of natural hazard is the possibility of advance warning and the ability to reduce or remove the NEO threat through mitigation such as deflection and evacuation. This work investigates the human vulnerability in the form of human injuries and fatalities expected from an NEO impact on Earth along with the ability to evacuate. New models have been developed to predict the potential human loss from six individual land impact hazards, using historical data about earthquakes and large explosions, models regarding roof collapse and casualties due to ignition exposure and the uncertainty in the data available. Models have also been developed that mimic human travel behaviour during an evacuation. These models were based on survey data regarding human behaviour during evacuations from hurricanes in the US along with models that estimate local road network capacity and flow-time. The development of a decision support toolbox, the Near Earth Object Mitigation Support System (NEOMiSS) supports this research. NEOMiSS is a collection of tools that individually and in collaboration provide useful information to decision-makers regarding human vulnerability (i.e. the number of human injuries and fatalities), ability to evacuate, physical impact effects and uncertainties in models, input data and risk corridor knowledge. This enables decision-makers to gain a better knowledge about the potential consequences of their decisions. A number of case studies were investigated using NEOMiSS. These illustrate how the impact location and impactor energy can result in very different outcomes with regards to human vulnerability. They also illustrate how local road networks and the location of local settlements along with the evacuation strategy affect the ability to perform a successful evacuation. The success of such an evacuation will influence the human vulnerability by reducing the number of expected casualties.