Zonal jets as transport barriers in planetary atmospheres
Beron-Vera, F. J.
Brown, Michael G.
Olascoaga, M. J.
Rypina, Irina I.
Udovydchenkov, Ilya A.
MetadataShow full item record
The connection between transport barriers and potential vorticity (PV) barriers in PV-conserving flows is investigated with a focus on zonal jets in planetary atmospheres. A perturbed PV staircase model is used to illustrate important concepts. This flow consists of a sequence of narrow eastward and broad westward zonal jets with a staircase PV structure; the PV steps are at the latitudes of the cores of the eastward jets. Numerically simulated solutions to the quasigeostrophic PV conservation equation in a perturbed PV staircase flow are presented. These simulations reveal that both eastward and westward zonal jets serve as robust meridional transport barriers. The surprise is that westward jets, across which the background PV gradient vanishes, serve as robust transport barriers. A theoretical explanation of the underlying barrier mechanism is provided. It is argued that transport barriers near the cores of westward zonal jets, across which the background PV gradient is small, are found in Jupiter’s midlatitude weather layer and in the earth’s summer hemisphere subtropical stratosphere.
Author Posting. © American Meteorological Society, 2008. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of the Atmospheric Sciences 65 (2008): 3316–3326, doi:10.1175/2008JAS2579.1.
Showing items related by title, author, creator and subject.
Measurements of a barotropic planetary vorticity mode in an eddy-resolving quasi-geostrophic model using acoustic tomography Lawrence, Wendy B. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1988-08)A tomographic array is placed in a 2-layer, flat bottom, steady-wind driven quasi-geostrophic circulation model to investigate whether the analysis of acoustic travel time changes can detect large-scale barotropic ...
Fox-Kemper, Baylor (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2003-06)Inertial terms dominate the single-gyre ocean model and prevent western-intensification when the viscosity is small. This occurs long before the oceanically-appropriate parameter range. It is demonstrated here that the ...
Pedlosky, Joseph (American Meteorological Society, 2010-05)A quasigeostrophic, two-layer model is used to study the baroclinic circulation around a thin, meridionally elongated island. The flow is driven by either buoyancy forcing or wind stress, each of whose structure would ...