As of January 2023, the GFM project has entered the second half of its work. Luca Molini, project manager for CIMA Research Foundation, explains what steps are planned for the coming years, the most relevant updates, and, most importantly, the role of this type of activity for flood risk management
Toward the end of January, Madagascar was affected by a flood that caused dozens of deaths and displaced people, partly because of the resulting landslides. Can one be immediately active in such an event, wherever in the world it occurs? Monitoring floods globally, and basically in real time, by scrutinizing them with the eye of satellites, is the idea behind Global Flood Monitoring (GFM), a monitoring system that allows for near real-time information, for every part of the world, so that we have an up-to-date picture of the situation and to take action timely.
Of this project, started in 2020 and funded by the European Commission, the kick off meeting was held with the beginning of 2023, marking the achievement of the first half of the work, which is in fact scheduled to end in 2026. There are several relevant updates for the coming years: the first is the availability of the data, accessible free of charge, also on the European EFAS – whereas before they were made available only on the global GloFAS platform – this means that, by analyzing a smaller area, the accuracy of the data is greater and, at the same time, there is greater visibility of the initiative at the European level.
A second important update comes from the upcoming launch of a new satellite. The Sentinel-1 mission on which GFM’s data collection relies is (or rather was) made up of two satellites equipped with synthetic aperture radars, which allow images to be collected in all atmospheric conditions, and thus also in the presence of clouds. or at night. At the end of 2021, however, one of the two satellites stopped working. “This did not prevent monitoring of the Earth’s surface, because in any case the orbits of both satellites covered the entire globe. The loss of one, however, means that it takes the much longer to have coverage of different areas of the world, and this is naturally problematic if the eventual flood does not last long,” explains Luca Molini, project manager for CIMA Research Foundation, which is part of the consortium as the person responsible for coordinating user support activities and technical and scientific dissemination. “This year, however, ESA will launch a new second satellite, allowing us to reset the monitoring time and frequency of data update, and consequently to be timelier in recognizing an event in progress”.
In addition to these novelties, there are some technical advancements and updates, mainly concerning the continuous improvement work for the algorithms used to analyze satellite data in order to continuously improve their quality. Part of the work will focus, for example, on attempting to reduce false alarms while increasing the correct detection of floods. In addition, the consortium will also work to improve data dissemination within the Copernicus portfolio, for example by making sure that civil defense agencies have targeted access to their area of expertise, and by improving comparisons with past events.
“Satellite-based monitoring services typically work on-demand, that is, the activation request occurs when a flood has already occurred,” Dr Molini explains. The images processed by GFM, on the other hand, are open access and always available to users, who can thus monitor the situation in near real time, that is, with images made available as soon as the satellites fly over the area of interest. In fact, this service complements and strengthens the awareness systems represented by GloFAS and EFAS, which also provide a forecasting part”.
The activities carried out under GFM are certainly not an end in themselves: if anything, they create some important synergies in several other projects. For example, CIMA Research Foundation is a partner in the ARISTOTLE project, led by the Italian National Institute of Geophysics and Volcanology,which provides the Emergency Response Coordination Centre (ERCC), Europe’s emergency response coordination center, with a system of forecasting and monitoring services on disasters of natural origin. Flood information and data collected by GFM contribute to bulletins issued periodically by ARISTOTLE, thus also providing confirmation of the soundness of a forecast (or the presence of a flood).
GFM also fits in among the many of our activities that are highlighting the vital role of satellites in the monitoring and management of extreme events, helping not only to track an ongoing event, as was the case last year during the floods in the Marche region, but also, as was the case in Pakistan, to provide an assessment for needs after the event is over. Or, again, satellites can help us manage the entire hydrological cycle, estimating with increasing resolution parameters that contribute to floods and droughts such as evapotranspiration and precipitation – as the DTE Hydrology project has highlighted.
“In general, we can certainly say that satellites are becoming increasingly relevant in the area of monitoring and risk management, and not only with regard to floods,” Dr Molini concludes. “Not surprisingly, the Copernicus Emergency Management Service, which provides information for both emergencies and preparedness and prevention activities, plans to focus its next meeting (to be held in February) precisely on developments in GloFAS and GFM products.”