Friday, 1 March 2024
12:00 – 13:00 CET


The city of Venice is situated inside the Venice lagoon at the northwestern end of the Adriatic Sea, a marginal sea in the Mediterranean. Here some of the highest tides in the Mediterranean help in flushing out brackish waters and replacing it with marine waters from the coastal shelf in front of the lagoon. The city has been nominated a UNESCO world heritage site due to the beauty of its buildings and churches and its unique setting with its canals and its gondolas. However, climate change is threatening this delicate system. If IPCC projections are right we could have a sea level rise between 30 cm and 1 meter, depending on the RCP scenarios considered (IPCC, 2001, 2007, 2014, 2021). Other semi-empirical models predict up to 175 cm of sea level rise (Vermeer and Rahmstorf, 2009). It is clear that for a city that is on average situated only 80 cm above mean sea level, such an increase in water level would not be sustainable. It is therefore of utmost importance to see how the city can be safeguarded against this global threat.

In the last years, construction of the mobile barriers (MOSE) has started in order to be able to defend the city of Venice against high tides and storm surges (Magistrato Alle Acque, 1997). The starting date of these works was 2003, however, even if now over 97 % of the works have been completed, it is still not yet clear when the whole works will be finished and operational. A possible date of completion is now (in 2023) the year 2025. However, 15 years ago the completion date was 2014 (Water Technology, 2019), so nothing sure can be said about when the MOSE will be finally finished. In any case, it would be interesting to see how the MOSE and the climate change with its sea level rise will be able to defend the city against high water. Other studies have looked into the climate impact on the city. A study (Umgiesser et al., 2006) has explored two possible values of sea level (30 and 50 cm) to see how often the barriers had to be closed and its implication on ship traffic. Based on a static analysis of the tides, another study (Carbognin et al., 2010) estimates the number of closures with a SLR of 50 cm to be around 250. Other studies looked at the economic implications of the closures (Vergano et al., 2010). Finally, an article on the impact of the operations of the mobile barriers has been published (Umgiesser, 2020) which shows that between 300 and 400 closures would be needed (once a day) for an SRL of 50 cm.


Georg Umgiesser is working as a director of research at the National Research Council in Venice. He is heading a group of scientists that mainly study lagoons and the coastal zone with numerical modeling. Special interests are the development of numerical models, sea-lagoon interaction, storm surge forecasting, and teaching on discretization techniques and oceanography. One of the major topics is looking at the future of Venice under climate change. He is the Italian coordinator of the DANUBIUS-RI infrastructure. He has published more than 100 peer-reviewed articles, with an h-index of 47.

This webinar is the second in a series of Seminars, organized by the FEEM Research Program “Climate Change Adaptation (Adapt@VE)” and Ca’ Foscari University on Venice Lagoon.

Read the press release on the February 8, 2024 seminar