Climate Change and the European Water Dimension - Agri ...

Remote sensing and satellite images
Remote sensing techniques are used daily for a number of purposes and updated
techniques are applied, merging information coming from instruments passing over
the lagoon at different altitudes and carrying different sensors (planes, balloons,
satellites). Morphological changes due to the combined effect of vegetation
distribution and tidal forces (both subjected to climate change) have been extensively
studied in the last years. The presence of many reference points on the lagoon
surface makes the Venice site very valuable for satellite analysis and calibration,
(e.g. NASA projects MODIS and SeaWifs).
Biomarkers and bioindicators
In the last years, several research campaigns were carried out with the aim of
evaluating the environmental health of the Lagoon by means of the biomarker
approach applied to marine bivalves (Livingstone et al., 1995, Nasci et al., 2002).
Several studies have shown how the biological response can be affected not only by
chemical pollutants but also by a number of natural stressors such as temperature,
salinity, hypoxia, food availability and the reproductive cycle of the sentinel organism
(Nasci et al., 2000). The expected effects of climate change related to changes in
environmental factors may be measured also through biological tools already
developed
Impact mitigation
For the comprehensive defence of Venice and of the inhabited areas of the lagoon
from high tides, including extreme events, the “MOSE system” has been created. The
system includes mobile flood barriers constructed at the lagoon inlets in order to
isolate the lagoon from the sea in the case of tides higher than the pre-established
height, the so-called “complementary measures”. These engineering works increase
the friction in the canals at the lagoon inlets with the scope of diminishing the level of
the most frequent tides, and strengthening local defences by “raising up” lagoon
banks and public pedestrian areas in the lowest lying areas.
The long-term effect of this intervention has been the focus of much scientific and
public concern and discussion, involving both social and natural sciences. The
detailed environmental and economic evaluation of the measures, also in terms of
technical effectiveness will certainly characterise the scientific (and possibly the
political) debate in the coming years.
Conclusion
The Venice lagoon can be considered as an early sentinel of global changes, due to
the existence of both anthropogenic and natural characteristics and pressures that
typify coastal lagoons. The availability of large data-sets, of a highly experienced
scientific community and significant international interest guarantee a fast and
reliable transfer of knowledge to other sites and a proper evaluation of general
information concerning global change and possible suitable mitigation measures.
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