1. Assistant Professor, Dept. of Environmental, Earth and Ocean Sciences, Univ. of Massachusetts Boston, 100 Morrissey Blvd., Boston, MA 02125 (corresponding author). E-mail: Ellen.Douglas@umb.edu; formerly, Research Scientist, Water Systems Analysis Group, Institute for the Study of Earth, Oceans, and Space, Univ. of New Hampshire, Durham, NH 03824.
2. Professor, Dept. of Civil and Environmental Engineering, Tufts Univ., Medford, MA 02155. E-mail: Richard.Vogel@tufts.edu