Modeling of the urban heat island pattern based on the relationship between surface and air temperatures

• Published in: Idoejaras Vol. 114; no. 4; pp. 287 - 302
• Main Authors: UNGER, J, GAL, T, RAKONCZAI, J, MUCSI, L, SZATMARI, J, TOBAK, Z, VAN LEEUWEN, B, FIALA, K
• Format: Journal Article
• Language: English
• Published: Budapest Hungarian Meteorological Service 01.10.2010
• Subjects: Convection, turbulence, diffusion. Boundary layer structure and dynamics; Earth, ocean, space; Exact sciences and technology; External geophysics; Meteorology; Hungary; Central Europe; Europe; Szeged; surface and air temperatures; Night; Hungary; urban environment; source area; Surface temperature; remote sensing; Microclimate; Modeling; Urban heat island; Atmospheric temperature; Thermal imaging; Aerial survey
• ISSN: 0324-6329

The aim of this study is to develop a new - and easy to use - method for early night-time near-surface air temperature pattern estimation based on surface temperature data in urban areas. The surface temperature data have been collected by an airborne thermal infrared sensor at an altitude of 2000 m above ground level. The study area was covered by hundreds of images with a spatial resolution of about 2 m. The measured values were calibrated with data of in situ surface measurements of different land use types. Simultaneous air temperature measurements were carried out using a carbased temperature sensor along an almost 12 km long N-S urban transect. The measured points were located using a GPS device. Data were processed with GIS methods, including newly developed algorithms. In order to find the relationship between air and surface temperatures a wider environment, the source area which determines the air temperature at a given point and time was taken into account. Using a source area with a radius of 500 m, a strong relationship was detected between the two parameters. Namely, the temperatures of the surfaces found in the surroundings (weighted by the distance) determine the temperature of the air parcel located at a given point. The obtained regression equation was applied to extend our results in order to model the air temperature field in a larger urban area.