Design of a satellite-based solution to the wildfires problem in the Mediterranean region

This thesis is a early phase design of a space mission in which the goal is to develop a service that, based on small satellites, is able to address the wildfire problem in the Mediterranean area with reliable fire forecasting and active monitoring. Wildfires are becoming a serious issue in the Mediterranean area, as in 2022 more than 2700 fire events caused an area loss of more than 800 hectares, with a trend that is rapidly worsening. Major initiatives to tackle this phenomenon are taken by the Copernicus programme of the European JRC, in which is developed the idea of using remote sensing as a tool for rapid mapping to support rescue teams in case of natural disasters as wildfires, but there’s still some gap in the current operational approach. Namely, this mission aims to satisfy two primary needs: improving fire-forecasting accuracy and providing near real time fire monitoring and high-resolution mapping. To date, fire forecasting is based on Fire Weather index (FWI), an index based on weather data that does not use any info about vegetation conditions. In this thesis it is therefore proposed to enrich FWI with Fuel Moisture Content (FMC), a visible and SWIR band-based index estimating water content in vegetation which has been shown would improve fire-forecasting accuracy. Here it comes one of the primary activities the constellation should perform: collecting visible and SWIR imagery over the whole area of interest once every 10 days. As far as active monitoring is concerned, this is currently carried out by the fire fighters who physically perform on-site inspections, so it can take several hours to begin the first rescue operations after a fire has started. In this thesis, a satellite constellation with near real-time fire monitoring and high-resolution mapping capability is presented. Here it comes another one of the primary functions the constellations should perform: scanning the Mediterranean area with a temporal resolution less than 1 hour, identifying fire spots and mapping them with a Ground Sample Distance (GSD) of less than 10 m, and sending mapping product directly to fire fighters close to the affected location. Once these science goals are established, several mission concepts and architectures have been evaluated using STK simulation tools as the main tool to identify the optimal mission configuration. In this context, several technological and design challenges are underlined and tackled, such as the necessary numerosity of the needed constellation and the advanced technological solutions the mission must adopt to ensure necessary performances, for example about the propulsion system and in particular the payload system, where it is unavoidable to design one of the instruments from scratch since none of off-the-shelf alternatives meets all the identified measurement requirements. Once the technical study over the mission is done, the thesis is concluded with considerations about cost and value of the services offered by the mission and about the technological achievements that, in future years, could noticeably improve performances or reduce cost and complexity of the mission realisation.