Assessing Land Surface Temperature in Urban Areas Using Open-Source Geospatial Tools

Abstract

Abstract. Land surface temperature (LST) in urban areas can be traditionally observed by thermal remote sensors. The increasing availability of 3D city models provides an alternative approach based on geospatial modeling. Using solar radiation tools and scripting in GRASS GIS, we have developed a physically-based LST model that can be used to estimate LST in urban areas represented by vector 3D city models. It uses standard input parameters such as solar irradiance, albedo or convection heat transfer coefficient for urban surfaces. The solar irradiance is estimated using the v.sun solar radiation add-on module in GRASS GIS. The LST values are calculated using map algebra operations using a Python script. The suggested methodology was applied to the study area in the city of Košice, Slovakia. Results indicate that urban morphology has a strong impact on spatial distribution of LST during the daylight hours. The accurate parameterization of urban surfaces can increase the accuracy of the model that can be used for urban planning, optimization of energy use in buildings or mitigation of urban heat island effects.

Trends and Evolution of the GIS-Based Photovoltaic Potential Calculation

“…The concept of LoD involves spatial resolution, requiring increasing precision when moving up in the scale. Twelve papers describe the LoD of the used dataset: [53,66] are limited to LoD1, [45,46,82] to LoD2, and [47,76,84] to LoD3. Moreover, it is interesting to note that in three cases, multiple Levels of Detail are considered in the same study, making the study multi-resolution.…”

“…Helbich et al [43], looking for a correlation between the potential energy production and the housing market through the hedonic prices method; • Hofierka [45], using solar energy predictions to correct land surface temperature estimations; Three of the analyzed studies [16,52,76] focused on single buildings, with two others [37,73] assessing public transport stops. While the attention was focused on single elements, the surrounding context was crucial.…”

“…[55] also proposed an extension of the r.sun calculation to 3D, though an add-in for city models-named v.sun-had been previously developed. This was used in [45] for the city of Košice (Slovakia), where a LoD2 city model was available.…”