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In the present paper, an active landslide located to the southeast of the urban area of Alcoy (Alicante, Spain) is analysed. This landslide affects the N-340 road, as well as an area in which some industrial buildings dated from the fifteenth century and catalogued as Places of Cultural Interest are placed. This region is characterised by the existence of a steep relief composed of materials from the Miocene to the present, on which many gravitational movements are developed. The displacements have been analysed using high-resolution spotlight mode SAR images captured by the Spanish SAR satellite PAZ (which operates at X-band), which were processed by advanced differential SAR Interferometry (A-DInSAR). The behaviour of the instability has been determined using InSAR-derived time series displacement maps. Additionally, the study has been completed with a detailed geomorphological mapping at 1:2000 scale and an analysis of structural damage carried out in situ. The landslide was modelled in 3D, from a deterministic and probabilistic point of view, confirming the global instability of the area and the relationship of the landslide with rainfall and the construction of a new road. The integration of all this information obtained and its subsequent analysis has made possible to precisely define the extension of the instability, its kinematics, and to identify the main triggering factors. This information will be crucial for the proper management of this landslide by the local authorities. This work was supported by the ESA-MOST China DRAGON-5 project with ref. 59339, by the Spanish Ministry of Science and Innovation, the State Agency of Research (AEI), and the European Funds for Regional Development under grant PID2020-117303 GB-C22, and by the Conselleria de Innovación, Universidades, Ciencia y Sociedad Digital in the framework of the project CIAICO/2021/335. All the PAZ images were provided by INTA (National Institute of Aerospace Technology) as part of PAZ-Ciencia (Scientific Exploitation of PAZ, project nr. PAZ-AO-001–025).

Satellites are part of daily life, so it's surprising to realise that there are still important gaps in the services they provide. Hydroterra will pioneer continuous radar imaging over Europe and Africa so that rapid weather and land surface processes can be imaged to reveal new science and enable important new services. Hydroterra is a novel mission concept which offers a remarkable range of capabilities and which could have a significant impact on the sciences of weather forecasting, hydrology, and the mountain cryosphere, as well as providing direct benefits to society. The mission focusses on capturing and understanding relatively rapid land-atmosphere processes related to the water cycle and the solid Earth. Hydroterra is designed to help scientists unravel details of the daily water cycle. Some of the main challenges come from processes which occur over periods of a few hours and at local, kilometre, scale. Current satellites may provide only 1-2 images per week, or have such large footprints that details of the local weather patterns are difficult to resolve. These challenges led to the definition of the following science goals for the Hydroterra mission: - Capture and understand these fast processes for improving the modelling capability for intense rainfall and related flooding and landslides, - Improve understanding of the diurnal water cycle related to soil moisture and snow melt/re-freeze, - Enable near real-time acquisition and analysis of ground motion (and response management) for landslides, earthquakes and volcanoes.

C-band RADARSAT-2 quad-Poland X-band COSMO-SkyMed incoherent dual-polarization PingPong SAR data are used to monitor corn fields phenology. The polarimetric analysis carried out at C-band shows a sensitivity of polarimetric observables to corn phenology that allows to interpret the different polarimetric signatures occurring along the cultivation cycle. Unfortunately, at the X-band, a physical interpretation is not properly provided, due to the unavailability of radar acquisitions for the most of the cultivation cycle. This is due to defense requirements which caused conflict acquisitions with the planned COSMO-SkyMed SAR data.

A physics-based electromagnetic model specially tailored for the computation of the radar backscatter from rice crops is being developed. The model produces estimates of the coherent polarimetric backscatter response as a function of the sensor parameters and the physical description of the scene. This model is currently under validation against experimental data gathered in the European Microwave Signature Laboratory (EMSL). First results, obtained by a direct comparison of simulated and measured backscattering coefficients (with HH, HV and VV polarizations), show a reasonable agreement. The dependence on incidence angle, frequency and morphological characteristics of the rice plants is currently being assessed.