By Marios Tzouvaras, Postdoctoral Researcher
from the ERATOSTHENES Centre of Excellence
Infrastructure is designed to be operational
under normal circumstances and to cope with rainfall, snow and excessive heat.
However, extreme natural hazards can lead to severe problems not only at the
areas where such events occur, but also at neighbouring regions or even the
entire country.
The identification of areas susceptible to land movements and the
systematic monitoring of land displacement at areas of interest in Cyprus, such
as areas with critical infrastructure, areas of Cultural Heritage and other urban areas, can be carried out through Earth Observation
techniques and space
technologies. Nowadays, Copernicus satellite data such as those from
the Sentinel missions as well as image processing software are freely
available.
Coherent Change Detection (CCD) and
Differential Interferometric Synthetic Aperture Radar (DInSAR) methods,
exploiting a series of Sentinel-1 SAR images, can be used for monitoring land
displacement caused by earthquakes and landslides, affecting different areas in
Cyprus. SAR technology allows for monitoring during day and night, irrespective
of the residing weather conditions. These methods were applied successfully in three case study areas that were selected based on
the site geology and the risk that land movements can cause to the general
public and to critical infrastructure. One of them was at the
embankment of the A6 Limassol-Paphos motorway in the direction from
Paphos to Limassol between exits of Avdimou and Pissouri, that partially
collapsed on 15 February 2019 after heavy rainfall, resulting in the closure of
the motorway, causing delays to
thousands of commuters every day for over a month.
The integration of these techniques for the
systematic identification of areas susceptible to natural hazards, such as
earthquakes and landslides, and the continuous monitoring of such land
displacement phenomena based on the analysis of optical and SAR satellite data,
can lead to a systematic way of monitoring land movements on a larger scale.
Rapid detection and more detailed products can be developed using the proposed Earth
Observation methodologies, for the detection and monitoring of natural hazards
and their impact on critical infrastructure resilience.
The proposed methodology might lay the
foundations for the development of an automated Early Warning System that will
facilitate the operation of the country’s emergency mechanism and warn public
authorities and the general public in a timely manner for an upcoming danger.
Moreover, it can also serve as a guidance/consultation tool for public
authorities and decision-makers regarding the identification of high-risk areas
in terms of land displacement on time and the adoption of preventive protection
measures on Cultural Heritage landscapes and critical infrastructure.
The present study was carried out under the
PhD course of studies of the Department of Civil Engineering and Geomatics at
the Cyprus University of Technology (CUT), within the activities of the
ERATOSTHENES Centre of Excellence (ECoE) (https://eratosthenes.org.cy/), and under the auspices of the ‘EXCELSIOR’ –
ERATOSTHENES: Excellence Research Centre for Earth Surveillance and Space-Based
Monitoring of the Environment Horizon 2020 Widespread Teaming project (https://excelsior2020.eu/). ‘EXCELSIOR’ has
received funding from the European Union’s Horizon 2020 research and innovation
programme (Grant Agreement No 857510) and from the Government of the Republic
of Cyprus through the Directorate General for the European Programmes,
Coordination and Development.
