1. Water Management and Hydrologic Sciences, Texas A & M University, College Station, Texas 77843, United States
2. Geology and Geophysics, Texas A & M University, College Station, Texas 77843, United States
3. Soil and Water Science, University of Florida, Gainesville, Florida 32611, United States
4. Marine Science Laboratory, Pacific Northwest National Laboratory, Sequim, Washington 98382, United States