For environmental-effects research related to energy technologies and their use, focusing on the impacts of climate and atmospheric changes on the physiology, growth, and biogeochemical cycles of North American forest ecosystems.
For pioneering research and development of new materials for advanced energy technologies, including materials for (a) the storage of nuclear waste, (b) the solid-state generation of electrical power directly from heat, and (c) the lossless transport of electricity.
For his pioneering research in atom probe field-ion microscopy and atom probe tomography, most recently to understand the unprecedented properties and behaviors of nanostructured ferritic steels.
For far-reaching accomplishments on national security issues relating to nuclear weapons proliferation, security of nuclear materials, and counterterrorism.
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.