Road Surface Temperature Modeling
Jason Covert: email@example.com
Robert Hellström: firstname.lastname@example.org
Municipal and state highway departments and private contractors are on the front lines to keep roads open and safe for travel during winter weather events. Despite their best efforts, there remains a need to improve the system in which road clearing efforts are
based. Excess spreading of deicing compounds on roadways poses environmental risk and drains municipal resources. There lacks of a method predict road surface conditions in coastal areas such as Southeastern Massachusetts where the geography is very heterogeneous. A predictive model utilizing Geographic Information Systems (GIS) would provide a birds eye view of a given road network to reveal where road clearing/deicing efforts should be focused. At Bridgewater State University, we are working to develop such a model using road surface temperature as a proxy for predicting road conditions.
Covert, J. M., and Hellström, R. Å., 2015: An Indirect Method for Predicting Road Surface Temperature in Coastal Areas with Snowy Winters. Proceedings of the 71st Eastern Snow Conference. Boone, NC, USA.
Model input and output
The model is fairly simple. It is inputted with the air temperature from a nearby weather station and a categorical variable associated with the land use type surrounding the road (ie. forest, commercial, water). A digital elevation model of the road network and its surrounding area can then be modified to better represent objects such as roadside trees and buildings which shade the road in various places. Unshaded roads naturally see more sunlight and are generally less prone to freezing. Using a solar radiation model embedded in ESRI’s ArcMap software, the modified digital elevation model is processed with consideration of time of day and the sun angle to produce an estimate of solar irradiance for every pixel in the scene. The irradiance is then combined with other inputs in the model in order to produce an approximated road surface temperature over the entire scene. Some post-processing is required to produce the output map shown below.