Human-enhanced tsunami hazard in large lakes
Worldwide, human-induced erosion enhances sediment delivery to lake deltas, increasing their susceptibility to collapse. In Lake Iseo, northern Italy, two millennia of intensified land use tripled sediment flux, oversteepening the delta and preconditioning it for failure. Here we show from geological records and numerical simulations that earthquakes in 1117 CE (Mw 6.5) and 1222 CE (Mw 6.0) triggered major subaqueous delta collapses, generating massive tsunamis with maximum run-ups of ~50 m and ~13 m, respectively. Historical accounts from the Vatican Library and archeological evidence support these reconstructions. Since the last collapse, eight centuries of human-induced erosion have rebuilt the delta, leaving shoreline populations highly vulnerable to future earthquake-triggered failures. A global lake synthesis showed that human-driven erosion has reached its highest levels since the Industrial Era, progressively overloading deltas worldwide; thus, similar catastrophic failures may become more likely in the future. These findings reveal a persistent, human-amplified mechanism of lacustrine tsunami generation and intensity with major implications for hazard assessment.
Authors
- William Rapuc (ORCID: https://orcid.org/0000-0001-8258-4545)
- Denys Dutykh (ORCID: https://orcid.org/0000-0001-5247-2788)
- Pascal Vuillemin
- Pierre Sabatier (ORCID: https://orcid.org/0000-0002-9620-1514)
- Raphaël Paris (ORCID: https://orcid.org/0000-0003-4569-5187)
- Muhammad Naveed Zafar (ORCID: https://orcid.org/0009-0005-7430-0123)
- Flavio S. Anselmetti (ORCID: https://orcid.org/0000-0002-8785-3641)
- Andrea Piccin
Institutions
- University of Bern (CH)
- Centre National de la Recherche Scientifique (FR)
- Oeschger Centre for Climate Change Research (CH)
- Khalifa University of Science and Technology (AE)
- Durham University (GB)
- Observatoire de Physique du Globe de Clermont-Ferrand (FR)
- Laboratoire d’Analyse et de Mathématiques Appliquées (FR)
- Lombardia Informatica (Italy) (IT)
- Institut de Recherche pour le Développement (FR)
- Université Savoie Mont Blanc (FR)
- Université Grenoble Alpes (FR)
Publication Details
- Journal
- Nature Communications
- Published
- 2026-10-15
- DOI
- https://doi.org/10.1038/s41467-026-78272-8
- Primary Topic
- Earthquake and Tsunami Effects
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- Ministère de l'Enseignement supérieur, de la Recherche et de l'Innovation
- Université Savoie Mont Blanc
- Khalifa University of Science, Technology and Research
- Ministère de l'Education Nationale, de l'Enseignement Superieur et de la Recherche
- Centre National de la Recherche Scientifique