USGS - science for a changing world

2015 Birdsall-Dreiss Distinguished Lecturer: Clifford I. Voss

Clifford Voss, 2015 Birdsall-Dreiss Distinguished Lecturer. Clifford I. Voss has been selected as the 2015 Birdsall-Dreiss Distinguished Lecturer by the Geological Society of America (GSA) Hydrogeology Division. Cliff is a senior scientist with the National Research Program of the U.S. Geological Survey (USGS), currently working in Menlo Park, California. Cliff, an internationally recognized expert in groundwater modeling, has over 35 years of project management, implementation, field work and research experience in groundwater systems, including: computer model development and effective model use for scientific evaluation of hydrogeologic systems; groundwater resources development, management and protection; coastal and island groundwater resources subject to seawater intrusion; and use of the subsurface for energy production/storage and toxic waste isolation. Cliff advises extensively on groundwater system evaluation and management and he lectures worldwide on these and related subjects. His scientific interests in hydrogeology include addressing hydrogeologic heterogeneity, physics of solute and energy transport, behavior of fluids with varying density, phase change in geothermal and frozen systems, inverse modeling and network design, and evaluating extensive aquifer systems in light of sparse data.

The practical methodology and models that Cliff and his colleagues developed are now widely used for managing both the quantity and quality of water supply. In particular, the SUTRA computer code, developed and maintained by Cliff and USGS colleagues, has been a standard tool for groundwater resource assessment ever since USGS made it publicly available in 1984. SUTRA has made possible hundreds of practical and research investigations globally since its release.

Examples of Cliff's work include: nuclear waste repository safety (Germany, Japan, Sweden), transboundary water resource management (Nubian Aquifer of Egypt, Libya, Sudan, Chad), sustainability of water supply (arsenic-free groundwater supply from the Bengal Aquifer of India, Bangladesh), groundwater management in coastal areas subject to saltwater intrusion (USA), evaluation of water resources emergency (2004 tsunami in Thailand), and assessment of climate-change impacts on permafrost-mediated hydrology in cold regions (Alaska, USA), in part using simulation methodology for groundwater flow with freeze/thaw developed by Cliff and colleagues.

Cliff is the Executive Editor of Hydrogeology Journal, the official journal of the International Association of Hydrogeologists (IAH), which has become a premier venue for worldwide progress in theoretical and practical hydrogeology and groundwater-resource management under his twenty years of leadership. Hydrogeology Journal is co-sponsored by GSA's Hydrogeology Division.

For more information on Cliff's work and a list of his publications, please visit

How to Request a Visit

The Birdsall-Dreiss Distinguished Lecturer tour is sponsored by the GSA Hydrogeology Division. GSA will pay travel expenses, and the host institution will provide local accommodation and meals and, if needed, some local travel expenses. Cliff needs to organize several lectures in each region to make effective use of the travel funds, so lecture requests received by 15 December 2014 will be given priority when Cliff organizes his tour schedule.

Upon request, Cliff will present one of the three lectures listed below. All three lectures are appropriate for a general audience with some science background or interest. To request a visit to your institution please use our lecture request form. You can also contact Cliff by e-mail at with any questions.

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