Combination of Lidar Elevations, Bathymetric Data, and Urban Infrastructure in a Sub-Grid Model for Predicting Inundation in New York City during Hurricane Sandy

摘要: We present the geospatial methods in conjunction with results of a newly developed storm surge and sub-grid inundation model which was applied New York City during Hurricane Sandy 2012. Sub-grid modeling takes novel approach for partial wetting drying within grid cells, eschewing conventional hydrodynamic method by nesting containing high-resolution lidar topography fine scale bathymetry each computational cell. In doing so, is heavily dependent on building street configuration provided DEM. The spatial comparisons between FEMA's maximum extents yielded an unparalleled absolute mean distance difference 38m average 75% areal match. An in-depth error analysis reveals that modeled extent contour well correlated FEMA most areas, except several distinct areas where differences special features cause significant de-correlations two contours. Examples these errors were found to be primarily attributed lack representation Jersey region grid, occluded highway underpasses artificially blocking fluid flow, DEM source FEMA. Accurate urban infrastructural critical terms modeling, because it uniquely affects flux through cell side, ultimately determines water depth flooding via distribution volume Incorporation buildings allow improve overall metrics from 32m area match 80% minimal additional effort.