This award will provide supplementary support to enable Dr. Rand Decker of the University of Colorado to conduct collaborative research for six months with Dr. Tsutomu Nakamura of the National Research Center for Disaster Prevention, Institute of Snow and Ice Studies, Niigata, Japan. They will survey the state of the art in ground based snow structure data collection techniques in Japan, and examine methods and algorithms for microwave remote sensing of the water-equivalent of snow. The considerable snowpack structure data that is available in Japan will be incorporated into a data base for the snow hydrology research community. Experiments on the interaction of microwave signals with snowpack structures characteristic of various periods during the winter season will be performed and correlated with the known properties of the snowpack. Remote sensing of snowpack liquid content is not yet an independent experimental technique since sensing data must be correlated with the grain size within the snowpack in order to obtain usable information on liquid content. In addition, both grain size and grain morphology of snowpack change over the course of a winter. Dr. Decker's experience in the area of snow avalanche hazard forecasting--which depends on snowpack structure--will complement the experience of the collaborating laboratory in the development of techniques for determining liquid content of the snowpack, from space.
