For his internationally recognized accomplishments in high-energy physics, radiation transport, and detector and neutron target research and development.
For significant contributions and leadership in the processing and properties of materials, particularly intermetallic alloys, which have led to his reputation as one of the world's leading scientists in these areas.
For distinguished research on the air/surface exchange of atmospheric trace gases and particles and their interactions with the Earth's biogeochemical cycles, and for pioneering developments in atmospheric sampling methodologies with special emphasis on the global mercury cycle.
For pioneering research in ecosystem theory, ecological modeling, error analysis, hierarchy theory, and landscape ecology and for the development of basic applications in risk assessment and regional environmental analysis.