What is the main role of AVT and its daughter AVT-ASI in the USAGE project?

AVT and its company daughter AVT-ASI are responsible for geospatial data production from aerial surveys. AVT has five airplanes at disposal for flights in Europe, and a number of sensors for the acquisition of data with different characteristics. Generally aerial surveys are done with photogrammetric cameras or LiDAR sensors for 2D and 3D surface mapping with a very high level of geometric detail. In USAGE aerial surveys are conducted with special sensors too, like thermal and hyperspectral cameras, that allow to capture spectral information not visible to the human eye.

What are hyperspectral aerial images and what is their role for environmental monitoring?

Hyperspectral aerial images are images acquired by hyperspectral sensors, that are able to collect information in hundreds of narrow bands across the electromagnetic spectrum. Additionally the sensors are not only sensitive to the visible part of the spectral range (350 – 750 nm, from blue to red), but also in the infrared part. Hyperspectral cameras varies with respect to the band widths and the spectral range. In AVT we fly with an hyperspectral camera that acquires 384 bands in the VNIR (visible near infrared) and SWIR (short-wave infrared) ranges, that is from 350 to 2.500 nm. Each object or material on the surface reflects the visible and infrared light differently and this response can be plotted in so-called “spectral response curves” or “spectral signatures”, that are a sort of “spectral fingerprint” of the object. Thanks to the high number of bands and the width for the spectral range, hyperspectral aerial images show much more detailed signatures than multispectral images and thus provide the ability to distinguish the material on the ground and on the roofs. Their role is therefore to allow the extraction of thematic information from a city related to the environment. For example it is possible to map the type of material and detect the presence of pollutant, like asbestos, or to map the different tree species in public and private areas. Moreover the spectral bands can be combined to provide indices that describe bio-chemical information on the vegetation, water or soil, for example the quantity of water and the health status of vegetation or the level of soil fertility.

How geospatial data can support the implementation of some European Green Deal priority actions?

Any action dealing with urban monitoring and planning needs detailed information on the cities of interest and to map this information on reality-based georeferenced products. Geospatial data in two or three dimensions represents the basic layer for that. It is important that the data are updated, accurate and complete.