Conference Agenda

The structural health of manmade infrastructures such as buildings, highway, railways, bridges, tunnels, subways, airports, dams, and reservoirs is of great significance for the sustainable development of human society and economy. Infrastructure stability is not only determined by its internal structural degradation, but also affected by potential geological hazards in the surrounding environment as well as anthropogenic disturbances. Therefore, it is an essential task to perform infrastructure health surveillance to ensure its long-term operation safety, for which surface deformation is regarded as an effective indicator of structural health status and thus should be monitored regularly. As a cutting-edge Earth observation (EO) technology, the interferometric synthetic aperture radar (InSAR) technology can obtain surface deformation through interferometric processing of two radar images acquired in repeat-pass mode. The Sino-European Dragon Program provides an opportunity for the joint exploitation of multi-source EO data to facilitate deformation monitoring and health diagnosis of infrastructures and surrounding geologic environments. However, it is still a challenge to comprehensively use the abundant EO data to achieve high-precision intelligent monitoring of infrastructure deformation and reliable health diagnosis.

In this project, we plan to take InSAR technology as the main means to develop accurate health status monitoring tools for infrastructure. For this purpose, the monitoring will include not only the infrastructure itself but also the surrounding geological environment as well as modeling the deformation rules, all with the help of multi-source EO data. The term multi-source consists of multiple aspects including diversity of observation geometry, frequency or bands, polarization, image resolution, and ancillary data acquired in-field. The primary outcome will be more reliable sequential dynamic monitoring and infrastructure health degradation diagnosis. This project will facilitate win-win cooperation between both Chinese and European teams, promote satellite utilization and data sharing, and provide technical training and international exchange for young scientists in multi-source EO-based surface deformation monitoring. It is believed that the completion of this project will boost technical development for the engineering application of EO-based infrastructure health monitoring technology, which can ensure the safety of people’s lives and property and identify the potential geological hazards that pose significant threats to human lives.

The aim of this project focuses on the development and application of processing methodologies to address the 3D characterization of sub-surface targets using stacks of spaceborne SAR data acquired over natural scenarios. The investigated applications will include 3D imagery of forests, ice sheets, and desert areas, and are therefore mapped into Dragon topic Solid Earth - Subsurface target detection. The topics above are of fundamental importance in the context of present and future spaceborne SAR missions, which will allow increasingly more systematic use of multiple acquisitions thanks to improved hardware stability and more strict orbital control. Specifically, the proposed activities are intended to support use of multi-pass data stacks from:

• the upcoming P-Band mission BIOMASS.
• in-orbit L-Band missions, such as the Argentinian SAOCOM constellation, the Chinese missions LuTan-1 & LuTan-4, and potentially ALOS-4 and NISAR.

Research activities will consider SAR data stacks acquired by P- and L-band spaceborne SARs over dense tropical forests, ice sheets, and desert areas, as well as campaign data from ESA campaigns such as TomoSense, AfriSAR, AlpTomoSAR, IceSAR and the Second Tibetan Plateau Scientific Expedition and Research led by the Chinese Academy of Sciences (CAS). The activities will be concentrated on processing SAR image stacks to extract information about vertical vegetation structure and sub-surface terrain topography in forested areas, and also about the internal structure of sand dunes in desert area as well as snow-ice volume in glacier area. Estimation and compensation of ionospheric and tropospheric propagation effects will be investigated as well. Leveraging the unprecedented availability of P-Band spaceborne data from the BIOMASS mission, the research will as well be extend to investigating the 3D of the ionosphere. Whenever possible, validation activities will exploit the availability of reference data gathered at campaign sites, for which we plan to analyze spaceborne acquisitions at the same sites.

In this Dragon-6 project Northeastern University (China) and National Institute of Geophysics and Volcanology (INGV, Italy

) research teams jointly plan to monitor the deformation associated to industrial activities and volcano dynamics in Northeast China. These objectives are the natural follow-up of the successful research activities of the previous DARAGON-4/5 projects. In this proposal, a new study site will be considered, the Songliao Basin, where ground subsidence caused by both natural phenomena and anthropogenic activities are occurring. In fact, the Songliao Basin, consisting in a Mesozoic-Cenozoic continental basin characterized by relevant oil and gas extraction activities, is a very interesting site to be deeply investigated by means of remote sensed data.

The main goal for the selected sites is to identify and characterize the processes responsible for the ground deformation (volcano dynamics, fluid migration, slope mass movement and human activities). The results will be relevant for the assessment of the hazard connected to the different natural and/or anthropogenic phenomena, providing the base for risk prevention and early warning. The Earth Observation data will be integrated with ground based data, to provide a comprehensive view of the relationships between surface deformation and sub-surface dynamics.

The main research objectives are to detect, quantify, and study the temporal evolution of ground deformation measured through remote sensing data, and characterize the processes and the hazards mainly due to:

1. anthropogenic activities at Fushun and Songliao Basin (mining and oil/gas extraction);
2. volcano dynamics at the Changbaishan volcano;

The areas exposed to natural and anthropogenic ground deformation will be defined, providing the fundamental information for the prevention and damage mitigation actions to be planned from Local Authorities. Probably the most useful methodology to achieve such objectives is represented by the joint analysis of multi-source EO and in situ data: InSAR time-series (MT-InSAR), VNIR optical data series, seismic data, geochemical data, oil/gas extraction data, and the subsequent modeling. Moreover, the retrieved deformation patterns will be validated with leveling and GNSS data (if available), and through cross-comparison between ascending and descending MT-InSAR results. Tailored for diverse requirements, we could monitor the phenomena using SAR images acquired from sensors operating in different frequency bands (e.g. C-band and L-band).

Based on the detected surface deformation and the possible correlation between volcanic and seismic activity, we will model the degassing and magmatic activity in the volcanic areas along with exploring the correlation between deformation and amount of oil/gas extraction or fluid pumping in deep wells.

Finally, the proposed research plans to carry out training for both the European and Chinese team researchers, and experience exchange for the Young Scientists granted by the project’s fundings.

The United Nations (UN) Sustainable Development Goals (SDGs) highlights the crucial need for boosting resilience in at-risk populations and agricultural systems to withstand extreme climate-related events, specifically landslides and land subsidence. These disasters carry grave implications, leading to numerous deaths and significant economic damages every year. Mountainous regions, particularly susceptible to landslides, experience sudden and disastrous events that present considerable hurdles in mitigation measures. Furthermore, landslides serve as additional hazards in continent-wide earthquakes, intensifying the severity of the disasters. On the other hand, land subsidence is rapidly developing into a serious geohazard, with forecasts predicting it will affect millions of people globally by 2040, impacting the global population substantially. Against this backdrop, the joint European Space Agency (ESA) and the Chinese Ministry of Science and Technology (MOST) Dragon-5 initiative cooperation project ReSeLMAIN project (ID: 95355, REmote SEnsing for Landslide Monitoring and impact Assessment on INfrastructure) aims to use remote sensing techniques, like Synthetic Aperture Radar Interferometry (InSAR), to identify and map landslides and land subsidence. It will monitor these geohazards and assess their impact on infrastructure. The main objective is to combine various remote sensing data and techniques. This integrated approach will enhance understanding and management of landslides and land subsidence, and will help mitigate disasters and make infrastructure more resilient. Four key components make up the methodology: First, InSAR automatically will be used to find and map geohazards. Secondly, different sensors like LiDAR, SAR, and optical remote sensing will be combined. Thirdly, data from in-situ and remote sensing will be merged. Finally, early warning systems will be set up for proactive risk control. Consequently, this comprehensive approach will contribute significantly to improving landslide and subsidence risk management, facilitating proactive measures for disaster resilience and infrastructure protection.