Simulation of Asteroids Impacting Earth: Tsunami Generation and Consequences on U.S. Major Cities for Disaster Response and Management Preparedness

Date: 4/26/2019

Time: 04:15 PM

Room: Pike

A hypothetical asteroid-impact scenario (https://cneos.jpl.nasa.gov/pd/cs/pdc19/) designed by the International Academy of Astronautics (IAA) is used as the basis for discussion and analyses of the table-top exercise. The asteroid is classified as a potentially hazardous asteroid with a diameter initially estimated between 100-300 meters. The large size uncertainty is due to uncertainties in both albedo and absolute-magnitude values. As the object is tracked over subsequent months, its impact-risk region is estimated to be much longer than the diameter of the Earth, but its width is only about 70 kilometers. The intersection of the uncertainty region with the Earth creates a risk corridor across the surface of the Earth. The corridor wraps more than halfway around the globe, spanning from the Hawaii on the western end, across the U.S. and Atlantic Ocean, and all the way to central and southern Africa on the eastern end. Given the significant water-impact probability, and because most of the potentially affected coastal regions are heavily populated, we focused our simulation efforts on modeling water impacts at several locations along the asteroid risk corridor. We have simulated the problem from asteroid entry, to ocean impact, to wave/tsunami generation, propagation, interaction with the shoreline and the flooding of the coastline major US cities. We have simulated three different asteroid diameters (100, 200 and 300m) and we have delimited the zones of inundation for each scenario for risk assessment and disaster management & response. The interaction of the asteroid with the ocean are simulated using the hydrocode GEODYN, creating a hydroacoustic signal, and also generating water wave source for the Boussinesq-based water-wave-propagation code, WWP. Run-up and flooding were simulated using WAST – water/structure – a CFD code for urban flooding assessment. Results are displayed with high resolution in Google Earth for all major coastal US cities. We will demonstrate these new capabilities and we illustrate the consequences at the local and global scales.

Presenting Author: Souheil M. Ezzedine

Authors