Moxim, W. J., 1990: Simulated transport of NOy
to Hawaii during August: A synoptic study. Journal of Geophysical
Research, 95(D5), 5717-5729.
Abstract: Using data sets generated by the Geophysical Fluid Dynamics
Laboratory general circulation/transport model's U.S.-Canada combustion
nitrogen source experiment, a detailed analysis of the simulated transport
mechanims producing the observed August NOy
maximum at Hawaii is presented. Combustion nitrogen is not simply advected
from the United States to Hawaii by the winds circulating around the climatological
subtropical anticyclone. Rather, its transport results from a complicated
three-way interaction of surface advection from source regions, enhanced
vertical diffusion due to dry convection, and winds in the "free troposphere."
Backward trajectories from Hawaii using model pressure and isentropic surfaces
were insufficient in explaining the transport. Model-consistent three-dimensional
trajectories revealed that the transport originated in the "free troposphere"
along a path from northern Baja to the Texas Gulf coast. Combustion nitrogen
from the source regions of southern California and as distant as the Texas
Gulf area is advected along the surface toward the arid areas of Baja,
the desert southwest, northern Mexico, and west Texas. Dry convection then
vertically mixes the air to pressures of 800-650 mbar, where the subsiding
wind flow from the east-northeast transports the NOy
to Hawaii. Observed wind fields and heights of dry convection are compared
to the model where data are available.