Towards More Resilient Communities – 3rd UC Lifeline Week Rome: 20-21-22 April 2015, L’Aquila: 23 April 2015, Naples: 24 April 2015
End-user and resilience oriented researches: creating worldwide networks Sapienza University of Rome
A simplified real time method to forecast semi-enclosed basins storm surge Paolo DE GIROLAMO
Sapienza University of Rome
[email protected]
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Abstract • Physical phenomenon • Storm surge in Adriatic • Protection of Venice from flooding • Storm surge forecast in semi-enclosed basins
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Storm Surge - Physical phenomenon Flooding of coastal area can occurs during storms. The phenomenon is due to strong winds blowing towards the coast which cause the increase of the mean sea-level. This phenomenon is commonly named storm-surge
Low atmospheric pressure = storm conditions
STORM SURGE
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Storm surge - Physical phenomenon Storm surge increases with the increasing of the wind velocity and with the extension of the continental shelf. CONTINENTAL SHELF
North Sea
Bay of Bengal
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Storm surge in Adriatic sea Adriatic sea. Most extended continental shelf of the Mediterranean sea
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Storm surge in Adriatic sea Wind blowing from south-east (named “Scirocco” )
Excitation and amplification of long period oscillations. STORM SURGE
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Storm surge in Adriatic sea Venice
Flooding of the Venice Lagoon - “Acqua Alta” Pescara
Flooding of Pescara 7
Protection of Venice from flooding Venice
Bocca di Lido
Bocca di Malamocco
Bocca di Chioggia
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Protection of Venice from flooding Planview of the protection system
Foundation caissons
Protection of Venice from flooding FLAP GATES Rest position Lido inlet
Cavallino Littoral
Lido Littoral
Pellestrina Littoral
Malamocco inlet
Chioggia inlet
Air immission
Working position
Storm surge forecast in semi- enclosed basins Three approaches can be used for the storm surge forecast: - STATISTICA METHODS - Based on meteorological predictors; - NUMERICAL MODELLING - The hydrodynamic equations of the basin are solved by using a deterministic approach; - MIXED METHODS - Based on statistical correction of numerical results.
Storm surge forecast in semi- enclosed basins Three approaches can be used for the storm surge forecast: - STATISTICA METHODS - Are computationally cheap, even they are not physics based; - NUMERICAL MODELLING – Shows large computational costs; - MIXED METHODS attempt to overcome the limits of previous approaches, still having high computational costs.
Storm surge forecast in semi- enclosed basins The actual challenge is to implement a real time forecast system that has to be reliable and computationally cheap at the same time.
The proposed method uses a mixed approach: physics based results are improved by using a statistical correction.
Storm surge forecast in semi- enclosed basins
Dynamic response of the basin to a unit wind stress
Unit wind stress
Storm surge forecast in semi- enclosed basins
Dynamic response of the basin to a unit wind stress
Unit wind stress
The basin response is obtained by applying the superposition principle
Storm surge forecast in semi- enclosed basins
Measurements
bias
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“raw level time series” to be improved
Storm surge forecast in semi- enclosed basins Statisctical correction
Artificial Neural Network
Storm surge forecast in semi- enclosed basins PI= Point of interest
Astronomical tide
Forecasted total sea level Measured total sea level
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Thanks for your attention
