Vertical land movement for the Italian coasts by altimetric and tide gauges measurements

The difference between the surface height observed by satellite altimetry and tide gauges gives an estimation of vertical land movements. We use this approach for determining vertical crustal movements along Italian coasts. The major problem with the altimetry is to acquire data near to the coastlines. We explore satellite data statistically to understand in which tide gauge stations the methodology of comparison with the satellite observations can be applied. We analyze the two different datasets (tide gauges and satellite altimetry) in order to determine under which circumstances it is possibile to calculate the tectonic rates from the sea level trends differences. We try to approach the coast as much as possible and we determine the apparent tectonic rates in 12 selected stations along Italian coastlines. We found subsidence in Puglia coasts and in Lampedusa station, uplift in Liguria Sea littoral and stability along the central coasts of Italy, like in Cicitavecchia and in Ancona. The results are complementary to vertical land movements achievable with GPS.