Japanese tourists having fun in the acqua alta.
Acqua alta, or "high water," can make Venice feel like Atlantis. At its worst, in 1966, acqua alta flooded the city with more than a meter of salty lagoon water; more typically, visitors notice water splashing over canal banks or bubbling up through drains in the Piazza San Marco.
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The phenomenon is often mistaken for proof that Venice is sinking. Although the city did sink about 10 cm in the 20th Century because of industrial groundwater extraction, the sinking largely stopped when artesian wells on the mainland were capped in the 1960s. Today, subsidence is estimated at 0.5 to 1 mm per year, mostly due to geological factors and compression of the land beneath the city's millions of wooden pilings. A larger problem is the rising sea level, which will become an even bigger threat as global warming melts the arctic ice caps. Already, the frequency of acqua alta has increased from fewer than 10 times a year to more than 60 times a year in the last century.
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The phenomenon is often mistaken for proof that Venice is sinking. Although the city did sink about 10 cm in the 20th Century because of industrial groundwater extraction, the sinking largely stopped when artesian wells on the mainland were capped in the 1960s. Today, subsidence is estimated at 0.5 to 1 mm per year, mostly due to geological factors and compression of the land beneath the city's millions of wooden pilings. A larger problem is the rising sea level, which will become an even bigger threat as global warming melts the arctic ice caps. Already, the frequency of acqua alta has increased from fewer than 10 times a year to more than 60 times a year in the last century.
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Acqua alta occurs when certain events coincide:
A very high tide (usually during a full or new moon).
Low atmospheric pressure.
A scirocco wind blowing up the narrow, shallow Adriatic Sea,
A very high tide (usually during a full or new moon).
Low atmospheric pressure.
A scirocco wind blowing up the narrow, shallow Adriatic Sea,
which forces water into the Venetian Lagoon.
The phenomenon is most likely to take place between late September and April, and especially in the months of October, November, and December. By official definition, acqua alta occurs when the tide is 90 mm (3.54 inches) above normal high tide. Not all parts of the city are equally susceptible to flooding.
The phenomenon is most likely to take place between late September and April, and especially in the months of October, November, and December. By official definition, acqua alta occurs when the tide is 90 mm (3.54 inches) above normal high tide. Not all parts of the city are equally susceptible to flooding.
Nice trendy footwear (c:
