The U.S. National Science Foundation is seeking proposals for research on atmospheric chemistry. The program supports research on the sources, sinks, transport, and transformation of gases and aerosols in the atmosphere through models, observations, and experiments. The program encourages principal investigators from a wide variety of institutions and backgrounds to submit proposals. Some key aspects of the job include: • Research on atmospheric chemical processes • Study of chemical mechanisms in the atmosphere • Optical properties of gases and aerosols • Improved methods for measuring the concentrations of trace species and their fluxes into and out of the atmosphere • Formation of new particles and secondary organic aerosols • Modeling of atmospheric chemical processes The program is open to any type of entity, and proposals are accepted anytime.