TY - JOUR

T1 - A GIS-based Screening Workflow for Coastal Storm Surge Impact Assessments and Mitigation Action Consideration

AU - Balstrøm, Thomas

AU - Kirby, Jordan

PY - 2022

Y1 - 2022

N2 - Balstrøm, T. and Kirby, J., . A GIS-based screening workflow for coastal storm surge impact assessments and mitigation action consideration.A GIS-based screening workflow is presented, providing first overviews of storm surge–induced inundation impacts along coastlines and where to consider mitigative action. The modeling is based on analysis of a hydro-conditioned digital terrain model (DTM) in Esri's ArcGIS Pro environment targeting undergraduate students, professional municipality planners, federal agencies, and more. Unlike existing commercial inundation modeling software, this application works in a simplified timeless setting on steady-state surge levels. This is accomplished only at the cost of not predicting when a specific targeted location is inundated. In return, fast computations are obtained. First, it is demonstrated how the DTM is turned into a hydro-conditioned terrain model, DHyMSea, protecting surges from entering land where sluices, high-water flaps, etc., are present. Second, the inundation screening is initiated for a user-defined number of sea levels. The outputs are individual raster layers for each level showing inundation extents and depths. Also, outputs are produced for each modeled level to back trace where the inundation came from. Third, a combined raster shows the minimum surge level to inundate any cell in the DHyMSea. Fourth, when considered where to raise protecting dikes, they can be digitized and have their elevation values stamped onto the DHyMSea. Finally, the inundation scenarios can be re-executed to evaluate the mitigation impact; if necessary, the dikes' locations and elevation properties can be reconsidered, and the workflow re-executed once more. The workflow has proven successful in first assessments of inundation threats where sea levels are expected to rise significantly over the coming decades. Additionally, the workflow has proven successful in quality assessments of a DTM. To demonstrate the workflow's capabilities, storm surge consequences for the greater Copenhagen region's coastline in Denmark are discussed for inundation scenarios ranging from 1.0 m to 3.9 m above sea level in steps of 0.1 m.

AB - Balstrøm, T. and Kirby, J., . A GIS-based screening workflow for coastal storm surge impact assessments and mitigation action consideration.A GIS-based screening workflow is presented, providing first overviews of storm surge–induced inundation impacts along coastlines and where to consider mitigative action. The modeling is based on analysis of a hydro-conditioned digital terrain model (DTM) in Esri's ArcGIS Pro environment targeting undergraduate students, professional municipality planners, federal agencies, and more. Unlike existing commercial inundation modeling software, this application works in a simplified timeless setting on steady-state surge levels. This is accomplished only at the cost of not predicting when a specific targeted location is inundated. In return, fast computations are obtained. First, it is demonstrated how the DTM is turned into a hydro-conditioned terrain model, DHyMSea, protecting surges from entering land where sluices, high-water flaps, etc., are present. Second, the inundation screening is initiated for a user-defined number of sea levels. The outputs are individual raster layers for each level showing inundation extents and depths. Also, outputs are produced for each modeled level to back trace where the inundation came from. Third, a combined raster shows the minimum surge level to inundate any cell in the DHyMSea. Fourth, when considered where to raise protecting dikes, they can be digitized and have their elevation values stamped onto the DHyMSea. Finally, the inundation scenarios can be re-executed to evaluate the mitigation impact; if necessary, the dikes' locations and elevation properties can be reconsidered, and the workflow re-executed once more. The workflow has proven successful in first assessments of inundation threats where sea levels are expected to rise significantly over the coming decades. Additionally, the workflow has proven successful in quality assessments of a DTM. To demonstrate the workflow's capabilities, storm surge consequences for the greater Copenhagen region's coastline in Denmark are discussed for inundation scenarios ranging from 1.0 m to 3.9 m above sea level in steps of 0.1 m.

U2 - 10.2112/JCOASTRES-D-21-00097.1

DO - 10.2112/JCOASTRES-D-21-00097.1

M3 - Journal article

VL - 38

SP - 712

EP - 724

JO - Journal of Coastal Research

JF - Journal of Coastal Research

SN - 0749-0208

IS - 4

ER -