How to response to sea level rise and flooding has currently become a serious issue due to population growth and activity in coastal areas especially low-lying areas. It is predicted that 2100,600 million people will live on coastal flood plains below the 1000-year flood level. So protecting flooding must be significant consideration in future. The number of people at risk from annual flooding as a result of a 40 cm sea level rise and population increase is predicted to rise from today`s level of ten million to 50-80 million by the 2050s and 240 million by 2080.
Generic approaches to sea level rise
There are three generic approaches to rising sea levels, which are retreat, accommodation and protection as summarized in Figure 1.
– (planned) retreat: all natural system effects are allowed to occur and human impacts are minimized by pulling back from the coast via land–use planning, development control, etc.;
– accommodation: all natural system effects are allowed to occur and human impacts are minimized by adjusting human use of the coastal zone via flood resilience, warning systems, insurance, etc.;
– protection: natural system effects are controlled by soft or hard engineering (e.g. nourished beaches and dunes or seawalls), reducing human impacts in the zone that would be impacted without protection.
Figure 1: Generic approaches to adapt to responses to sea level rise
Case study / Venice, Italy
Venice is a city in northern Italy and the capital of the Veneto region and whose urban spaces are still radically transformed during periods of acqua alta, exceptionally high tidal waters of the Adriatic Sea enter the Venetian Lagoon. Elevated wooden platforms are then strategically placed throughout the city, creating new and specific pathways of movement. Therefore, some of existed pathways might also be temporarily disappeared during the acqua alta. During the acqua alta of December 2008 shown in Figure 2, the waters rose almost 5 feet (more than 1.5 m), which is the most significant flood of the last twenty-two years in Venice. In addition, when the water rising, it might engrave high water marks onto the venerable marble walls of the Ca’ Farsetti. This might be respected local accommodation as a response to sea level rise and flooding.
Venice’s Pizza San Marco with the Doge’s Palace under the acqua alta of December 1, 2008
Bergdoll, B. (2011), Rising currents: projects for New York`s waterfront, New York: Museum of Modern Art.
Church, J., Woodworth, P., Aarup, T. and Wilson, W. (2010), Understanding sea-level rise and variability, Chichester: Wiley-Blackwell.
Pugh, D. (2004), Changing sea levels: effects of tides, weather, and climate, Cambridge: Cambridge University Press.