Providing researchers with an important baseline of environmental data, the EAC houses sophisticated instrumentation to examine pollutants in groundwater, date prehistoric fossils, and analyze the composition of smog.
In the environmental chemistry and technology laboratory, collimated sunlight from the Linde + Robinson solar telescope is focused into photolysis reactors, where artificial photosynthesis processes are developed to convert water and carbon dioxide into energetic fuels.
Measurements of trace metals in the environment and precise dating of corals and cave deposits all require extremely clean conditions for processing samples. The clean room, custom designed for this purpose, is unlike any built earlier. It has air cleansed of almost all particles and has been constructed entirely from non-metallic materials. Measurements of corals and stalagmites in it reveal how climate has varied in Earth's past and how carbon cycles between the biosphere, the atmosphere, and the oceans.
The instrument lab houses three inductively coupled plasma mass spectrometers (ICP-MS). They are used to measure metal isotope ratios and Uranium-Thorium (U-Th) dates of samples that have been chemically processed in the clean room. They are also used to measure sulfur isotopes in the modern ocean and in ancient rocks to develop a quantitative understanding of how oxygen levels in the atmosphere have evolved over Earth's history.
The Atmospheric Chamber is designed for studies of the photochemical reactions of gaseous and particulate pollutants. In two large (1,000-cubic-foot) reaction chambers—the first of their kind when they were built—the chemical reactions that produce urban smog and atmospheric particles are investigated under precisely controllable conditions. They have revealed how the particles that make up smog form in the atmosphere. Research results obtained with them have been instrumental in designing effective air quality policies and in helping to understand the role of aerosols in climate.
In the laboratory for atmospheric chemical physics, the interactions of light with molecules in the atmosphere are investigated to elucidate how pollution forms and to measure the atmospheric concentration of aerosols and greenhouse gases. Techniques are developed for the global monitoring of the atmosphere from mobile ground-based laboratories and from space-based instruments.
The High-Precision Spectroscopy Laboratory is housed in a quiet room—a room with specially designed acoustic and electromagnetic insulation. Acoustic foam blocks sound waves and copper cladding around the entire room blocks electromagnetic waves. The noise-free environment allows us to achieve exquisite precision in laser measurements of radiative properties of greenhouse gases, aerosols, and atmospheric trace constituents: the properties of single molecules can be measured. The measurements are the basis for climate models and for planning satellite missions to measure the composition of the atmosphere from space.
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