Geodaysit 2023

The new EU programmes and funds aim to support the territories in facing the main challenges for development, combining a relaunch of competitiveness and sustainable and inclusive growth.
To address issues such as adaptation to climate change, the resilience of territories, and the protection of biodiversity and natural ecosystems, it is necessary to support traditional planning and monitoring methods with new and more effective systems capable of maximizing the effectiveness of policies and investments. In this context, Regione Piemonte, which has always been active in use of OSGeo, has developed a new methodology that will apply in the ERDF 2021-2027 PO 2 for urban heat islands (UHI) identification and monitoring its evolution over time. The tool involves using satellite images, made available by the United States Space Agency (NASA) and the European Space Agency (ESA), and their processing through the use of free software such as QGIS, SAGA, GRASS, Python, and R, etc. The analysis involves the combination of data deriving from the processing of a series of satellite images using their spectral indexes and data relating to the spatial distribution of the population most exposed to the effects of summer heat waves extrapolated from the associated demographic data to the census sections and provided by ISTAT. The indices derived from the satellite analysis identified for use were: the LST (Land Surface Temperature) which provides basic information relating to the distribution of temperatures in space and the NDVI (Normalized Difference Vegetation Index), able to highlight the vegetative state and considered strategic as it can describe the "beneficial" effects, in terms of decrease in ground temperatures, generated by the presence of vegetation. The data deduced from the suitably normalized spectral index maps were then combined with the demographic data to produce maps of the vulnerability of urban centers (all the cities of Piedmont with more than 10,000 inhabitants) to heat islands, helpful in identifying the most sensitive areas where to implement appropriate NBS (Nature Based Solutions) interventions. This analysis system is supported by a monitoring system that evaluates the effects of the adaptation interventions to be implemented, the LST and NDVI spectral indices have been evaluated on a seasonal basis on a ten-year historical series (2013/2022) on pilot areas. NDVI will be considered suitable for measuring the effects induced by urban transformations and therefore usable for quantifying the effectiveness of future NBS interventions financed by the new programming. The activity carried out up to now has highlighted the advantages of the combined use of open source data and free software: the remote sensing data provide updated and detailed information on land cover and make it possible to directly estimate certain physical and ecosystemic quantities of the territory while the Free software allows for extensive analysis capabilities for free.
The ongoing activity has allowed the development of a first proposal for a methodology that will be supplied as a support tool for planning and programming activities. This methodology, while showing some limitations as it analyzes only some aspects of the UHI phenomenon, presents interesting development potential that will be the subject of further study.