A GIS-enabled spectral library to disseminate field data for surface spectroscopy

Remote sensing from ground, UAV, aircraft and satellite platforms is increasingly central to monitoring Earth’s surface and supporting decision making. However, robust interpretation of multispectral/hyperspectral observations still depends on consistent links between satellite products and high-quality reference spectra measured in the field and laboratory, plus workflows that make these data interoperable across sensors, spatial scales and acquisition conditions. We present the INGV Spectral Library, a web-based, GIS-integrated platform designed to operationally connect in situ spectroscopy with airborne/satellite imaging spectroscopy, enabling reproducible pre-processing, cross-sensor harmonization, and geospatial querying of spectral datasets for environmental monitoring applications.

The platform provides standardized spectral analytics commonly required in monitoring pipelines: continuum removal and absorption-feature characterization, derivative-based enhancement to emphasize diagnostic features, and sensor-aware resampling using Spectral Response Functions (SRFs) to harmonize high-resolution field spectra to specific sensors (e.g., Sentinel-2 and spaceborne hyperspectral missions). This “sensor-to-field” alignment enables direct comparability and supports spectral–spatial data fusion, where field-based endmembers and satellite reflectance/emissivity products can be jointly analysed. A key component is the GIS interface: spectra are linked to georeferenced samples and metadata and can be filtered by location, lithology/land cover context, acquisition conditions and spectral criteria, facilitating rapid exploration of spatial patterns and targeted selection of reference signatures for mapping and validation tasks.

Two use cases illustrate the relevance to environmental monitoring and hazard-related contexts. (i) In Sardinia (Sale ’e Porcus), curated VNIR–SWIR FieldSpec measurements are ingested as a controlled reference set to support multi-sensor consistency checks and calibration/validation activities for satellite imaging spectroscopy. (ii) In Oman, PRISMA Level-2D surface reflectance is analysed through spectral indices and Spectral Angle Mapper (SAM), using PRISMA-resampled endmembers derived from reference spectra to delineate spatially coherent alteration patterns and potential copper-related signals; the resulting maps support field planning and prioritization of sampling targets, with new samples intended to validate and refine satellite-based interpretations.

By combining standardized spectral pre-processing, SRF-based cross-sensor harmonization, and GIS-driven access to reference spectra, the INGV Spectral Library provides a practical platform for multi-scale environmental remote sensing, enabling more transparent, transferable and decision-oriented workflows for monitoring surface changes and hazard-relevant processes.

This study is carried out within two projects: the Space It Up project funded by the Italian Space Agency, ASI, and the Ministry of University and Research, MUR, under contract n. 2024-5-E.0 - CUP n. I53D24000060005 and  PRIN2022_SH6_2022BTKA9Y-02 funded by  Ministry of University and Research, MUR CUP  D53D23000580006.