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Coastal zones in Europe accommodate large human populations and significant socio-economic activities. One-third of the EU population is estimated to live within 50 km of the coast, even though many coastal areas are prone to flooding from storm surges.
The height of the sea surface is most accurately measured using space-borne systems, such as satellite altimeters. The data collected from these altimeters have proved crucial in monitoring global sea-level changes and forecasting high seas.
This is why a permanent calibration facility for satellite radar altimeters, funded through SOFIA, an FP7 Research Potential programme, has been established on the island of Gavdos, 40 km south of Crete, Greece. This infrastructure, which is now fully operational, is one of only four permanent calibration (Cal/Val) sites in the world.
“The results obtained by the Gavdos infrastructure are compatible with the other sites, thus its contribution to the international debate on climate change is valuable,” says project coordinator Stelios Mertikas from the Technical University of Crete.
The project has also enabled the university’s Geodesy and Geomatics Engineering Laboratory (GeoMatLab) to establish a network of Global Navigation Satellite System (GNSS) reference stations for monitoring tectonic deformation and atmosphere delays from satellite signals. These stations are in the western part of Crete and Gavdos. A prototype microwave transponder for satellite-altimetry calibration has also been operated under the supervision of the European Space Agency.
Positive results from the SOFIA project have already been published in three scientific journals, while more than 20 oral and poster peer-reviewed presentations have been held in European and international workshops and conferences.
The project also addressed issues fundamental to the Lab’s long-term research success. “The SOFIA project assisted GeoMatLab in exploiting its strengths and overcoming its weaknesses,” explains Mertikas. “Specifically, the main problems for peripheral research institutes located in less-developed European regions, such as Crete, are in recruiting experienced researchers, and the absence of secure funding for the acquisition of infrastructure.”
As a result, a significant amount of EU financial support – about 45% of the overall budget – was actually allocated to recruiting the experts needed to establish the permanent satellite-calibration facility. The acquisition of new infrastructure, the development of a prototype instrument and the modernisation of existing infrastructure received about 20% of the budget.
Another major focus of SOFIA was on training activities, the mutual exchange of knowledge and building a global scientific network of dedicated Cal/Val sites. Exchanges between GeoMatLab and French, Austrian and German research institutes, for example, enhanced the Lab’s know-how in crustal deformation monitoring, by using the established permanent GNSS array in West Crete.
Greater international visibility for the Lab’s work in crustal-deformation monitoring recently led to the setting up of a strategic partnership between GeoMatLab and Wuhan University, China and installation of the first Chinese Beidou GNSS receiver (the Chinese GPS system) at the Technical University of Crete.
“Through EU funding and support, GeoMatLab is now internationally recognised as a valuable and indispensable member of the international satellite-altimetry calibration community,” says Mertikas. “The SOFIA project also enabled the Lab to evaluate itself and forge collaborations with well-established European and international institutes.”
However, Mertikas appreciates the need to sustain SOFIA’s strong results. “This can be done through European and international initiatives, either in satellite altimetry or in crustal deformation,” he explains. “Projects like, for instance, MyOcean or EPOS (European Plate Observing System) may take advantage of the important infrastructure established by SOFIA and support its maintenance.” The Lab also recently submitted a proposal under the European Commission’s Marie Curie International Research Staff Exchange Scheme (IRSES), together with French, Chinese and Indian partners.