The next Yosemite Forum is on Tuesday, February 14, 2012 from noon to 1pm in the Yosemite Valley Auditorium. The presentation will be "Simulation of Rockfall Trajectories Using Process-based Models" by Sandra Melzner, Geological Survey of Austria. Sandra Melzner is a geologist with the Department of Engineering Geology at the Geographical Survey of Austria, and works in the field of rockfall and landslide hazard assessment.