Climate Scientist: Venice Faces Growing Sea Level Rise Risks

The Planet Classroom Network and the POP Movement have released a new episode of their series, Net Zero Speaks, featuring Professor Marco Marani from the University of Padova. The episode focuses on Venice's vulnerability to rising sea levels and land subsidence. Professor Marani explains how the combined effect of rising oceans and sinking land, termed relative sea-level rise, exacerbates flood risks in low-lying coastal communities.

In the discussion, Marani highlights the importance of salt marshes, which provide natural flood defense. However, he warns that the marshes' ability to accrete sediment and organic material is threatened by accelerating sea-level rise. Estimates suggest approximately 50 percent of global salt marshes have already been lost.

Venice serves as a case study. Marani notes that while the MOSE storm surge barrier system is crucial for the city's survival, every engineering intervention has trade-offs. By blocking exceptionally high tides, MOSE prevents the natural sediment accumulation that nourishes salt marshes. Marani emphasizes that engineering solutions must be informed by biological and geological processes for long-term sustainability.

Marani urges coastal leaders to prioritize education, mitigation, and adaptation. He stresses the importance of engaging youth, integrating nature-based solutions with infrastructure, and planning for managed retreat in areas unable to relocate. "Protecting our coastlines requires more than building barriers," said Cathy Rubin, founder of Planet Classroom. "We must understand living ecosystems, plan for change, and act before climate impacts make our choices even harder."