Winter road maintenance in urban areas Part(II) Air and Road temperature variations

Road weather information systems (RWIS) for detection of risk of slipperiness are traditionally used for highway winter road maintenance. Knowledge about local climatological variations play a significant role in establishing these systems and also for the use and interpretation of the recorded data. Recently attention has been put on the possibility of accurate road weather information within urban areas.

This study focus on variations in air and road surface temperature which can occur within urban areas during winter conditions. Local climate variations within cities are analysed using data from road weather field stations located in various environments. The field stations within the RWIS.which are equipped with sensors for detection of air temperature and humidity at 2m, road surface temperature, wind speed and wind direction and also an optic sensor for detection of precipitation. The effect of urban environments on road climate which is dealt with in this study forms a base for a further analysis of the factors that lead to road icing, presented in part (II).

The effect of the urban heat intensity (UHI) is analysed together with different topogarphical features on the role of forming a variable spatial and temporal air and road surface temperature pattern.

An aim of the project is to incorporate the complexity of urban structure and urban heat island effects into the present road surface temperature forecast models. The benefit of this will be to increase the possibilities to issue pre warnings and effective winter road maintenance operations in urban areas.