A Numerical Model for Prediction of Road Temperature and Ice

Abstract

A numerical model for the prediction of road temperature and ice has been tested on data from a Danish road station. The model is based on the solution of the equation of heat conduction in the ground and the surface energy-balance equation. Sensitivity experiments have been carried out in order to assess the relative importance of the various active processes. Large model sensitivity has been found to the specification of atmospheric input data. It is important to specify a realistic temperature and cloud structure in the lower part of the atmosphere. The best results were obtained with a detailed temperature and humidity analysis using significant points in the applied radiosonde data. Some further improvement was obtained with a simple scheme capable of adjusting the initial atmospheric temperature profile for analysis bias. The results indicate that the model can be used for high-quality road-temperature forecasts up to a range of at least 3 h. This requires a coupling of the model to a realistic atmospheric forecast model and a careful treatment of road and atmospheric initial conditions.