Articles | Volume 21, issue 2
https://doi.org/10.5194/nhess-21-807-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/nhess-21-807-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Quantification of continuous flood hazard using random forest classification and flood insurance claims at large spatial scales: a pilot study in southeast Texas
Department of Marine Sciences, Texas A&M University at Galveston, Galveston, Texas, USA
Antonia Sebastian
Department of Marine Sciences, Texas A&M University at Galveston, Galveston, Texas, USA
Department of Geological Sciences, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
Russell Blessing
Department of Marine Sciences, Texas A&M University at Galveston, Galveston, Texas, USA
Wesley E. Highfield
Department of Marine Sciences, Texas A&M University at Galveston, Galveston, Texas, USA
Laura Stearns
Department of Marine Sciences, Texas A&M University at Galveston, Galveston, Texas, USA
Samuel D. Brody
Department of Marine Sciences, Texas A&M University at Galveston, Galveston, Texas, USA
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EGUsphere, https://doi.org/10.5194/egusphere-2025-2870, https://doi.org/10.5194/egusphere-2025-2870, 2025
This preprint is open for discussion and under review for Hydrology and Earth System Sciences (HESS).
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High quality weather event datasets are crucial to community preparedness and resilience. Researchers create such datasets using clustering methods, which we advance by addressing current limitation in the relationship between space and time. We propose a method to determine the appropriate factor by which to resample the spatial resolution of the data prior to clustering. Ultimately, our approach increases the ability to detect historic heatwaves over current methods.
Kieran P. Fitzmaurice, Helena M. Garcia, Antonia Sebastian, Hope Thomson, Harrison B. Zeff, and Gregory W. Characklis
EGUsphere, https://doi.org/10.5194/egusphere-2025-2049, https://doi.org/10.5194/egusphere-2025-2049, 2025
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Uninsured flood damage can destabilize household finances, increasing the risk of mortgage default. Across seven floods in North Carolina, 66 % of damage was found to be uninsured. Among affected mortgage borrowers, 32 % lacked sufficient income or collateral to finance repairs through home equity-based borrowing, increasing their risk of default. These findings suggest that uninsured flood damage poses a serious and under-recognized threat to mortgage borrowers and lenders.
Julius Schlumberger, Tristian Stolte, Helena Margaret Garcia, Antonia Sebastian, Wiebke Jäger, Philip Ward, Marleen de Ruiter, Robert Šakić Trogrlić, Annegien Tijssen, and Mariana Madruga de Brito
EGUsphere, https://doi.org/10.5194/egusphere-2025-850, https://doi.org/10.5194/egusphere-2025-850, 2025
Short summary
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The risk flood of flood impacts is dynamic as society continuously responds to specific events or ongoing developments. We analyzed 28 studies that assess such dynamics of vulnerability. Most research uses surveys and basic statistics data, while integrated, flexible models are seldom used. The studies struggle to link specific events or developments to the observed changes. Our findings highlight needs and possible directions towards a better assessment of vulnerability dynamics.
Yi Victor Wang and Antonia Sebastian
Nat. Hazards Earth Syst. Sci., 22, 4103–4118, https://doi.org/10.5194/nhess-22-4103-2022, https://doi.org/10.5194/nhess-22-4103-2022, 2022
Short summary
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In this article, we propose an equivalent hazard magnitude scale and a method to evaluate and compare the strengths of natural hazard events across different hazard types, including earthquakes, tsunamis, floods, droughts, forest fires, tornadoes, cold waves, heat waves, and tropical cyclones. With our method, we determine that both the February 2021 North American cold wave event and Hurricane Harvey in 2017 were equivalent to a magnitude 7.5 earthquake in hazard strength.
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Short summary
In southeast Texas, flood impacts are exacerbated by increases in impervious surfaces, human inaction, outdated FEMA-defined floodplains and modeling assumptions, and changing environmental conditions. The current flood maps are inadequate indicators of flood risk, especially in urban areas. This study proposes a novel method to model flood hazard and impact in urban areas. Specifically, we used novel flood risk modeling techniques to produce annualized flood hazard maps.
In southeast Texas, flood impacts are exacerbated by increases in impervious surfaces, human...
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