Open AccessThe applicability of similarity theory to a road surface
Author(s) -
Chen D,
Gustavsson T,
Bogren J
Publication year - 1999
Publication title -
meteorological applications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.672
H-Index - 59
eISSN - 1469-8080
pISSN - 1350-4827
DOI - 10.1017/s1350482799001036
Subject(s) - advection , sensible heat , similarity (geometry) , sign (mathematics) , temperature gradient , context (archaeology) , boundary layer , planetary boundary layer , surface layer , latent heat , turbulence , environmental science , energy balance , atmosphere (unit) , meteorology , potential temperature , surface (topology) , atmospheric sciences , mathematics , layer (electronics) , mechanics , geology , physics , thermodynamics , computer science , geometry , materials science , mathematical analysis , paleontology , composite material , artificial intelligence , image (mathematics)
The existing models for predicting road surface temperature are often based on surface energy balance which includes contributions from sensible and latent heat exchanges between the atmosphere and road surface. The similarity theory is usually applied to compute the atmospheric turbulent heat fluxes. However, the theory only applies in horizontally homogeneous situations, which is certainly not the case for road conditions. An investigation is carried out to see how much measured profiles of mean wind and temperature from a road meteorological station deviate from the profiles given by similarity theory. The difference between the data and the theory is revealed by comparing the observed gradients with the theoretical ones. The sign of the vertical gradients of all data and the relationships between two vertical gradients at different levels under near‐neutral conditions are examined. It is found that the measured profiles are all systematically different from the theoretical ones. The deviation is discussed within the context of the possible existence of an internal boundary layer. Moreover, detailed temperature profiles were measured to study the development of temperatures in the first 2.5 m. The results show that the sign of the temperature gradient reverses in a layer between 0.8 and 1.4 m and that a large change in temperature occurs in this layer; these effects were probably caused by local advection. Copyright © 1999 Royal Meteorological Society