השוואת שיטות

	Urban Heat Island Analysis	Urban Density Gradient Model
תחום	Urban Studies	Human Geography
משפחה	Process / pipeline	Regression model
שנת המקור	1982	1951
הוגה השיטה	Tim R. Oke (energetic basis of the UHI)	Colin Clark; Edwin Mills & Richard Muth (theory); Bruce Newling (quadratic form)
סוג	Measurement of the temperature excess of urban areas relative to their rural surroundings	Family of functional models of urban population density as a function of distance from the centre
מקור מכונן	Oke, T. R. (1982). The energetic basis of the urban heat island. Quarterly Journal of the Royal Meteorological Society, 108(455), 1–24.	Clark, C. (1951). Urban population densities. Journal of the Royal Statistical Society. Series A (General), 114(4), 490–496.
כינויים	UHI Analysis, Urban Heat Island Intensity, Surface Urban Heat Island (SUHI) Analysis, Land Surface Temperature Differential	Urban Density Function, Population Density Gradient, Density-Distance Function, Monocentric Density Model
קשורות	4	4
תקציר	Urban heat island (UHI) analysis quantifies how much warmer cities are than the rural land around them, a difference driven by impervious surfaces, reduced vegetation, waste heat, and street-canyon geometry that traps radiation. The intensity of the effect is defined simply as the urban-minus-rural temperature differential, a framework given its physical, energy-balance foundation by Tim Oke in 1982. Modern analysis increasingly maps the surface UHI from thermal satellite imagery, converting radiance to brightness temperature and then to land surface temperature so the heat island can be observed continuously across an entire metropolitan area rather than at a few weather stations.	The urban density gradient model is the broad family of functional relationships that describe how population density varies with distance from a city's centre. Its canonical member is Colin Clark's 1951 negative-exponential form, but the family also includes Bruce Newling's quadratic-exponential function that permits a density crater at the core, simpler linear and Smeed forms, and the economic micro-foundation supplied by the Muth-Mills monocentric city model. Together these give planners and economists a compact, comparable language for urban spatial structure.