Seifeddine Jomaa | TU Delft Repository

Reply to Comment by Darwish on “Soaring Building Collapses in Southern Mediterranean Coasts: Hydroclimatic Drivers and Adaptive Landscape Mitigations”

Journal article (2026) - Sara S. Fouad, Essam Heggy, Oula Amrouni, Abderraouf Hzami, S. Nijhuis, Nesma Mohamed, Ibrahim H. Saleh, Seifeddine Jomaa, Yasser Elsheshtawy, Udo Weilacher

We are grateful for Darwish's interest in our paper, Fouad et al. (2025, https://doi.org/10.1029/2024EF004883). In this reply, we show that Fouad et al. (2025, https://doi.org/10.1029/2024EF004883) did not attribute building collapses in Alexandria solely to hydroclimatic factors, as stated in the comment. Instead, we emphasize that hydroclimatic drivers are presented as accelerators, with other anthropogenic influences explicitly stated in the original paper. Moreover, our response proves that Darwish (2026, https://doi.org/10.1029/2025ef006885)'s simplistic statistical approach is physically incorrect and obscures absolute risk by normalizing actual building collapse rates to the total number of buildings within a city. Furthermore, our reply shows that the comment conflates the distinct measurement of soil relaxation using shallow isotope mapping at the city scale, as conducted in Fouad et al. (2025, https://doi.org/10.1029/2024EF004883), with deep structural geotechnical assessments for foundation design of individual buildings. The utility and complementarity of both methods are already discussed in Fouad et al. (2025, https://doi.org/10.1029/2024EF004883). We acknowledge that the statement on the “7,000 at-risk buildings” is only mentioned in the abstract and is inadvertently missed in the main text; however, the calculation leading to this result is detailed in our supplementary data set and methods. Accordingly, Darwish (2026, https://doi.org/10.1029/2025ef006885)'s comment, while appreciated, misinterprets Fouad et al. (2025, https://doi.org/10.1029/2024EF004883) and overlooks the contemporary literature on Alexandria's hydrogeological and coastal dynamic contexts and their implications for infrastructure instability. ...

Soaring Building Collapses in Southern Mediterranean Coasts

Hydroclimatic Drivers & Adaptive Landscape Mitigations

Journal article (2025) - Sara S. Fouad, Essam Heggy, Oula Amrouni, Abderraouf Hzami, S. Nijhuis, Nesma Mohamed, Ibrahim H. Saleh, Seifeddine Jomaa, Yasser Elsheshtawy, Udo Weilacher

The low-lying, arid coastal regions of the Southern Mediterranean Basin, extending over 4,600 km, face daunting sea level rise and hydroclimatic changes due to shifting weather patterns. The impact of these factors on coastal urban buildings and infrastructure must be better understood. Alexandria, a historic and densely populated port city in Egypt representative of several coastal towns in the Southern Mediterranean, has experienced over 280 building collapses along its shorelines over the past two decades, and the root causes are still under investigation. We examine the decadal changes in coastal and hydroclimatic drivers along the city's coastline using photogrammetric satellite images from 1974 to 2021. We explore the interconnectivity between shoreline retreat, ground subsidence, and building collapses. Our results suggest that collapses are correlated with severe coastal erosion driven by sediment imbalances resulting from decades of inefficient landscape management and urban expansion along the city's waterfront. This severe erosion, combined with sea level rise, increases seawater intrusion, raising groundwater levels in coastal aquifers. Degrading ground stability and accelerating corrosion in building foundations ultimately culminating in collapses. We identified a coastal area of high vulnerability with over 7,000 buildings at risk, surpassing any other vulnerable zone in the Mediterranean Basin. We propose cost-effective and nature-based techniques for coastal landscape adaptation to alleviate these dangers in Alexandria and other Southern Mediterranean cities facing similar climatic challenges. ...

Advancing river monitoring using image-based techniques

Challenges and opportunities

Journal article (2024) - Salvatore Manfreda, Domenico Miglino, Khim Cathleen Saddi, Seifeddine Jomaa, Anette Eltner, Matthew Perks, Salvador Peña-Haro, Thom Bogaard, Tim H.M. van Emmerik, More Authors...

Enhanced and effective hydrological monitoring plays a crucial role in understanding water-related processes in a rapidly changing world. Within this context, image-based river monitoring has been shown to significantly enhance data collection, improve analysis and accuracy, and support effective and timely decision making. The integration of remote and proximal sensing technologies with citizen science and artificial intelligence may revolutionize monitoring practices. Therefore, it is crucial to evaluate the quality of current research and ongoing initiatives to envision the potential trajectories for research activities within this specific field. The evolution of monitoring strategies is progressing in multiple directions that should converge to build a critical mass around relevant challenges to find innovative solutions that overcome limitations of traditional approaches. The present study reviews examples and good practices of enhanced hydrological monitoring in different applications, reflecting on the strengths and limitations of new approaches. ...

Combination of geostatistics and self-organizing maps for the spatial analysis of groundwater level variations in complex hydrogeological systems

Journal article (2023) - Emmanouil A. Varouchakis, Dimitri Solomatine, Gerald A. Corzo Perez, Seifeddine Jomaa, George P. Karatzas

Successful modelling of the groundwater level variations in hydrogeological systems in complex formations considerably depends on spatial and temporal data availability and knowledge of the boundary conditions. Geostatistics plays an important role in model-related data analysis and preparation, but has specific limitations when the aquifer system is inhomogeneous. This study combines geostatistics with machine learning approaches to solve problems in complex aquifer systems. Herein, the emphasis is given to cases where the available dataset is large and randomly distributed in the different aquifer types of the hydrogeological system. Self-Organizing Maps can be applied to identify locally similar input data, to substitute the usually uncertain correlation length of the variogram model that estimates the correlated neighborhood, and then by means of Transgaussian Kriging to estimate the bias corrected spatial distribution of groundwater level. The proposed methodology was tested on a large dataset of groundwater level data in a complex hydrogeological area. The obtained results have shown a significant improvement compared to the ones obtained by classical geostatistical approaches. ...