Recent studies on the land subsidence process of the Venice coastal area (Italy).

Venetian land subsidence, both natural and due to groundwater withdrawal, and eustasy have caused 23 cm of ground elevation reduction referred to the mean sea level over the last 100 years. Considering that the physical structure of the city is characterised by the presence of historic buildings in direct contact with the lagoon water and with the ground level only a few tens of centimeters above normal high tide level, this relative elevation loss has been vital for Venice's existence. After a short overview of the phenomenon occurred in the past, the actual trend is analysed by combining geodetic (high precision levelling) and remote sensing (InSAR and GPS) measurements. New data show the present ground stability of the central part of the lagoon, where the city of Venice is located, and sinking trends at the northern and southern extremities of the lagoon edges and at some places in the central and northern littorals