Project Sagebrush: Revisiting Short-Range Dispersion Using Modern Instrumentation
Both tracer technology and turbulence instrumentation have advanced significantly since the early studies. The Field Research Division (FRD) of the NOAA Air Resources Laboratory is planning a new series of tracer releases to revisit short-range dispersion in open terrain. These studies, called Project Sagebrush in a nod to Project Prairie Grass, will take place at the Idaho National Laboratory in Southeast Idaho using modern turbulence instrumentation and tracer technology. This project is planned to be a multi-year effort, with Phase 1 taking place in October 2013.
The primary tracer to be used in Project Sagebrush is SF6, with three different perfluorocarbons also available. FRD has approximately 150 bag samplers for measuring time-average concentrations together with ten trace-gas analyzers capable of measuring concentration fluctuations at 1 Hz. A 34-tower meteorological network, 915 MHz radar profiler with RASS, sodars, and sonic anemometers are available for measuring boundary-layer characteristics including turbulence. Collaborators are bringing additional instrumentation.
Phase 1 of Project Sagebrush will take place in October of this year. The focus of this phase will be dispersion in unstable to neutral atmospheric conditions. Five tracer releases are planned for the 4 Pasquill-Gifford stability categories A through D. An aircraft from the University of Tennessee Space Institute will be used for real-time vertical tracer sampling.
This presentation will compare and contrast Projects Prairie Grass and Sagebrush and provide preliminary results from Project Sagebrush Phase 1.