How have they saved Venice from the waters?
With a combination of natural restoration, “gray infrastructure”, such as dunes that protect from flooding and slow the energy of incoming water; and the engineering of mobile submerged barriers.
I read that your predictions three days before the floods have been providential.
By having a precise and accurate prediction of when the flood is going to occur – storms, winds, currents, sea level on the coast – we can launch the MOSE containment system.
Does it take three days to contain the waters?
Three days, yes; but submerged mobile barriers are saving Venice, although they complain that it is very expensive engineering.
I remember that the flood and the end of Venice was a recurring chronicle.
Well, there are no more chronicles from correspondents about the end of Venice with a wonderful and expensive work; but it was the only one that could save it as long as we had an accurate weather forecast three days in advance.
Wouldn’t predicting a storm and flood just a day in advance save Venice?
No, because the system requires those three days in advance to give the barriers time to deploy and be effective.
Well, congratulations: you saved Venice.
Now we need more precise and specialized forecasts to also defend our coast: all the coasts of the Mediterranean are in danger and even more so, yours.
Why more ours?
Because the Atlantic through the Strait of Gibraltar influences them more.
This year, like almost everyone, we have run out of sand in many: how to save them?
With the collaboration of engineers, oceanographers – rivers and their currents and the dragging of silt are essential – and meteorologists. If you know that in seven days a big storm is coming that will hit your coast, you can propose engineering solutions to protect it.
Put sandbags in a hurry?
We must also restore natural assets, such as dunes or corals, that human intervention, with the construction of ports or other infrastructure, and climate change deteriorate. Human engineering is not enough; we need that of the planet.
Are we still in time to recover our beaches?
Until 2010, scientists, engineers and businessmen, managers and politicians worked without organizing themselves. In the last decade we realized that without collaboration there would be no salvation. The case of Venice and its providential public-private collaboration can be useful for others.
Will we increasingly have better climate and ocean forecasts?
But we need data for the models to work. We need observations and I am sure that with them artificial intelligence will make a huge difference in prediction and engineering.
What do we need most urgently?
Europe must get to work now to have a sedimentary balance budget.
Have all the sediments of European rivers and beaches quantified?
We need to compute the sediments of rivers, reservoirs, coasts… Know if they are available to move and transport them and how they flow with the rivers.
Is it possible to measure them all?
Today we have the instruments to prepare that budget that would allow us to deploy a system of monitors that would save beaches, coasts and deltas.
I admit that it is better than the sacks.
Better than truckloads of sand, believe me, is planning, engineering and ecological restoration.
Why do we lose sand in Catalonia?
We are losing beaches all over the planet, because they are like living organisms and climate change affects them; but not only this, also the changes in the seabed. In the bed of the Po River, which I know well, we are running out of heavy gravel and instead have more and more fine sand.
Without gravel, will the coastline degrade?
Due to human action and the swamps for electrical energy, coarse gravel is transformed into fine sand; But there are many other factors that combine to destroy beaches, such as changes in temperature that modify the bed vegetation that fixed the sediments or destroy the corals that stopped flooding. Do you know which is the best truck to transport sand?
¿…?
The best sand truck is the ocean itself… if we restore its balance.
If not?
If it continues to degrade… They tell me at the UPC that on the Catalan coast the sea level rises 10 mm per year.
