Fine resolution satellite thermal data can be used as a basis for mapping the spatial distribution of urban surface temperatures and identifying urban hotspots. This dataset has been produced from satellite-derived land surface temperature (LST) data for the Greater London Area by ARTi Analytics BV as part of EXTREMA Global portfolio of services and reveals the city’s major daytime summertime hotspots. Outline methodology For spatial resolutions coarser than 30 m it can be reasonably assumed that the urban LST hotspots coincide with the urban air temperature hotspots1. Hence, thermal satellite data can be used so as to identify intra-urban areas with elevated temperatures. To generate a dataset that presents the LST spatial distribution and the corresponding hotspots for GLA, a five-year (2016-2020) time series of satellite-derived 100 m daytime LST images (in °C) is employed. The utilized data correspond only to summer months (i.e. June, July and August) so as to capture the hotspots with the most important impact on thermal discomfort, human health and energy demand, and are derived from Landsat-8 thermal infrared images. The next step after estimating the 2016-2020, average, summertime, daytime LST is to aggregate them to city block level. In addition to the average LST (avgLST), the avgLST standard deviation, minimum and maximum for each city block are also estimated. The aforementioned statistics are stored as new attributes in the Urban Atlas polygons and the updated vectors are then exported as a new shapefile. The spatial extent of this output shapefile corresponds to the boundaries of GLA.
