Evaluating the Operational Retrieval and Downscaling of Urban Land Surface Temperatures

The Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing of the National Observatory (NOA/IAASARS) has developed a system that retrieves and downscales thermal remote sensing data obtained from Meteosat Second Generation-Spinning Enhanced Visible and Infrared Imager (MSG-SEVIRI) in real time. This activity aims to facilitate the operational monitoring of the urban thermal environment by providing sharpened data in a timely manner. The system entered its operational phase in April 2014 by producing quarter-hourly land surface temperature (LST) data at an enhanced spatial resolution (1 km) for five major European cities. The current work briefly presents the system and exhaustively validates the generated time-series for the three summer months of 2014. The performance assessment was carried out by comparing the entire archive of generated LST data (i.e., more than 30 000 images) with similar independent and well-validated products. The results obtained indicate that both the LST retrieval and LST downscaling modules, which form the heart of the system, perform satisfactorily. The wealth of information made available through such exploitation of MSG-SEVIRI imagery in real time has the potential to fill a large gap in monitoring the thermal urban environment and support effectively the timely generation of higher value products and services related to energy demand and heat-related health issue.