California Partners for Advanced Transportation Technology

This report presents a review of alternative techniques to determine the presence of ice on road surfaces. It examines techniques ranging from passive, in-pavement technologies, to different remote sensing techniques. The author presents the Polarized Reflectance Infrared Signature Method (PRISM) technique which uses differences in measured near infrared reflectance between ice, water and dry road due to absorption, in addition to the effect of polarization to discount the contribution of specutacular reflectance off the front surface.