Slope Flow Measurements During Vertical Transport And Mixing (VTMX) Field Experiment, Salt Lake City, 2000

During the month of October 2000, a major field campaign dealing with urban flow and pollution dispersion took place in Salt Lake City, Utah. Named “Vertical Transport and Mixing” (VTMX) experiment, this project was funded by the US Department of Energy's Environmental Meteorology Program (EMP). The aim of VTMX was to investigate vertical transport and mixing in stable atmospheric boundary layer (ABL) of complex terrain, with emphases on weak or intermittent turbulence that occur under stable conditions, morning/evening transitions around urban basins or valleys, formation and evolution of inversions and the motion of pollutants within stable layers trapped in valleys. The overall research program is expected to contribute significantly to the knowledge of complex-terrain flow processes and will lead to better prediction of urban air quality. The Environmental Fluid Dynamics (EFD) Program at ASU is one of the several groups participated in this experiment. EFD’s research program was focused on thermally induced circulation, for example, slope and valley wind systems, pooling of cold air in basins and breakup of cold pools during which the trapped air is dispersed vertically. In addition to field measurements, laboratory, theoretical and numerical simulations are being conducted to better understand flow, mixing and transport in complex terrain. This paper contains some slope flow measurements taken during the VTMX program by the ASU/EFD group.