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In this letter, we propose an approach based on the use of Sentinel-2 spectral indices and self-organizing map (SOM) to automatically map burned areas and burned severity. These analyses were performed on a test area in Chania, located in Crete, affected by a fire (around 200 ha) that occurred from July 13, 2018 to July 28, 2018. The investigated area is characterized by heterogeneous land cover types made up of natural and agricultural lands. To identify different levels of fire severity without using fixed thresholds, we applied SOM to the three spectral indices normalized difference vegetation index (NDVI), normalized burn ratio (NBR), and burned area index for sentinel (BAIS) used to enhance burned areas. This is a particular critical issue because fixed threshold values are generally not suitable for fragmented landscapes, vegetation types, and geographic regions different from those for which they were devised. To cope with this issue, the methodological approach herein proposed is based on three steps: 1) indices computation; 2) maps of the difference of the three indices computed using the data acquired from prefire and postfire occurrences; and 3) unsupervised classification obtained processing all the difference maps using the SOM. The obtained results were validated using an independent data set, which showed high correlation with satellite-based fire severity.

This contribution is part of a project for the identification, research and protection of archaeological evidence in the village of Sant'Arsenio (SA), through the use of new technologies applied to archaeological research. In particular, the activity combines typical Remote Sensing tools (satellite data and UAVs), with a preference for open source software and open access databases, and common archaeological research practices (study of ancient and modern bibliographic sources, field survey, topographic analysis, etc.). Sant'Arsenio is a small town in the western part of Vallo di Diano, a large plain surrounded by mountains, between 450 and 480 m above sea level, located on the border between Campania and Basilicata. Information about the archaeological potential of the Sant'Arsenio appear to be relatively scarce compared to those available for the surrounding municipalities (Polla, Atena Lucana, Teggiano, Sala Consilina). This lack is due to the absence of systematic studies and planned archaeological research activities in the municipality. This paper presents the data collected between the end of 2018 and the beginning of 2019 by IMAA-CNR (Istituto di Metodologie per l'Analisi Ambientale del Consiglio Nazionale delle Ricerche). In particular, the satellite data (Sentinel-2), assisted by archaeological research, allowed to identify some anomalies of archaeological interest.

Since the mid-1980 s satellite remote sensing data have been used in forest fire monitoring for applications related to the diverse phases of fire management as, fire prevention, danger estimation, detection of active fires, estimation of fire effects (burned area mapping, fire severity estimation, smoke plumes, biomass losses, etc), post fire recovery, fire regime characterization, etc. Today satellite technologies can fruitfully support both research and operational activities for fire monitoring and management at different temporal and spatial scales and with cost effective tools. This paper provides a short overview of satellite remote sensing for forest fire danger estimation at different scale of observations.

This article is focused on the FIRESAT methodology developed for and funded by the Protezione Civile of the Basilicata Region. The fire monitoring system is based on satellite free of charge data and developed for the dynamic estimation of vegetation fire susceptibility and fire impact in forest and non-forestry ecosystems. The purpose of this fire risk system is the timely (daily) and detailed (from 1 km down to 30 m) monitoring of the vegetation and meteorological conditions which can affect the proneness of vegetation to fire. FIRESAT provides operational monitoring tools for a systematic forest fire management from risk estimation to fire severity mapping, including the estimation of fire damage on hydro-geological risk and vegetation fire resilience.

Up to nowadays, satellite data have become increasingly available, thus offering a low cost or even free of charge unique tool, with a great potential for operational monitoring of vegetation cover, quantitative assessment of urban expansion and urban sprawl, as well as for monitoring of land use changes and soil consumption. This growing observational capacity has also highlighted the need for research efforts aimed at exploring the potential offered by data processing methods and algorithms, in order to exploit as much as possible this invaluable space-based data source. The work herein presented concerns an application study on the monitoring of vegetation cover with the use of multi-temporal (2010-2014) satellite Modis data. The selected test site is the Iguazu park highly significant, being it one of the most threatened global conservation priorities (http://whc.unesco.org/en/list/303/). In order to produce synthetic maps of the investigated areas to monitor the status of vegetation and ongoing subtle changes, satellite data were processed using Principal Component Analysis (PCA). Results from our investigations pointed out an ongoing degradation trend.

This paper presents the results we obtained in the context of the FIRE-SAT project focused on the use of satellite data for pre-operational monitoring of fire danger and fire effects in the Basilicata Region. The use of satellite data was manyfold, to obtain: (i) fuel property (type and loading) maps, mainly obtained from satellite Landsat TM data, (ii) fuel moisture estimation (mainly from MODIS), (iii) fire danger/susceptibility indices as well as (iv) post fire effects including fire severity and vegetation recovery assessment. Results obtained during the first year of project (2008) suggested that the integrated model identified the main fire danger zones by means of the integration of fuel types with daily fuel moisture and Greenness maps. MODIS multitemporal data analyses enable us to dynamically estimate fire severity as well as to map fire affected areas and evaluate the vegetation recovery capability over time. The pre-operative use of the integrated model, carried out within the framework of the FIRE-SAT project funded by the Basilicata Region, pointed out that the system enables us to timely monitor spatial and temporal variations of fire susceptibility and promptly provide useful information on both fire severity and post fire regeneration capability.