1. Department of Physics, Astronomy and Geosciences, Towson University, Towson, Maryland
2. Mallinson Institute for Science Education, and Department of Geological and Environmental Sciences, Western Michigan University, Kalamazoo, Michigan
3. Department of Geography and Meteorology, Valparaiso University, Valparaiso, Indiana
4. Mallinson Institute for Science Education, and Department of Geography, Western Michigan University, Kalamazoo, Michigan