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Climate change and increase of extreme weather events, besides the numerous consequences, affect significantly and put in risk the agriculture sectors. Natural disasters, such as floods and wildfires, are responsible for a great loss in agriculture production. National governments together with international bodies make an important effort to cooperate towards the response and resilience when a disaster occurs. In this frame the European Earth Observation Programme - Copernicus provides a series of observation data, in-situ measurements and services related, amongst others, to different types of disasters. Concerning the availability of this big volume of observation data, the aim of DiAS (Disaster and Agriculture Sentinel Applications) project is to revise the existing knowledge on remote sensing methods for mapping the extent of natural and/or man-made disaster over agricultural areas and propose improvements. The developed methodology will be implemented in a Decision Support System (DSS), which will be freely available and easy-to-use by non-experts. In this paper, the developed methodology focuses on mapping floods over agricultural areas. Sentinel-1 and Sentinel-2 imagery are used as input information for the comparison analysis before and after the event. The reference for results' evaluation is the corresponding information delivered by Copernicus Emergency Management Service (EMS). Although, the evaluation results are in good agreement when they could be used, a reference of higher accuracy is needed in order to estimate accurately the quality of the output products. [ABSTRACT FROM AUTHOR]

The derivation of the radiative budget of urban environments has gained a high interest in the recent years as an essential part of the global energy budget of big cities. Urban 3D (three-dimensional) heterogeneity hampers its assessment with in-situ measurements, which stresses the interest of Earth Observation (EO) satellites. Improvements in remote-sensing technology and 3D urban databases open the way to new deterministic approaches. This paper presents a new method that derives maps of urban shortwave exitance, albedo and radiative budget * from EO satellite images (e.g. Sentinel 2, Landsat-8), using the discrete anisotropic radiative transfer model. In a preliminary step, it derives maps of urban material optical properties from an EO satellite image, at the spatial resolution of this EO image. The method is applied to the city of Basel, Switzerland, in the frame of the European Community H2020 URBANFLUXES (www.urbanfluxes.eu) project which aims at improving our knowledge on anthropogenic heat fluxes in European cities. Results are very encouraging. Indeed, urban * derived from 234 EO satellite images, ranging from 200 to 800 W/m2 through the year, is very close to in-situ measured *: ≈15 W/m2 temporal root mean square error (i.e. 2.7% mean relative difference) relative to measurements. [ABSTRACT FROM AUTHOR]

In this paper, the atmospheric precipitable water (PW) over the area of Cyprus was estimated by means of Advanced Very High Resolution Radiometer (AVHRR) thermal channels brightness temperature difference (ΔT). The AVHRR derived ΔT was calculated in a grid of 5 x 5 km cells; the corresponding PW value in each grid cell was extracted from Moderate Resolution Imaging Spectroradiometer (MODIS) Level 2 product (near-infrared algorithm). Once the PW -- ΔT relationship coefficients corresponding to the area of Cyprus were calculated, the relationship was applied to AVHRR data for one month period. Radiosonde derived PW values, as well as MODIS independent PW values were used to validate the estimations and a good agreement was noted. [ABSTRACT FROM AUTHOR]