HR: 0800h
AN: P51A-0202 [Abstracts]
TI: Zonal jets as transport barriers in planetary atmospheres
AU: Beron-Vera, F J
EM: fberon@rsmas.miami.edu
AF: RSMAS/AMP, University of Miami, 4600 Rickenbacker cswy, Miami, FL 33149, United States
AU: Brown, M G
EM: mbrown@rsmas.miami.edu
AF: RSMAS/AMP, University of Miami, 4600 Rickenbacker cswy, Miami, FL 33149, United States
AU: Olascoaga, M J
EM: jolascoaga@rsmas.miami.edu
AF: RSMAS/AMP, University of Miami, 4600 Rickenbacker cswy, Miami, FL 33149, United States
AU: * Rypina, I I
EM: irypina@rsmas.miami.edu
AF: RSMAS/AMP, University of Miami, 4600 Rickenbacker cswy, Miami, FL 33149, United States
AU: Kocak, H
EM: hk@math.miami.edu
AF: Department of Computer Science and Mathematics, Ungar Building 515
1365 Memorial Drive, Coral Gables, FL 33146, United States
AU: Udovydchenkov, I A
EM: iudovydchenkov@rsmas.miami.edu
AF: RSMAS/AMP, University of Miami, 4600 Rickenbacker cswy, Miami, FL 33149, United States
AB:
Recent theoretical and numerical work has shown that a stable - and apparently
preferred - mean flow pattern at midlatitudes on rapidly rotating large
planets is a sequence of alternating narrow eastward and broad westward
zonal jets. The corresponding potential vorticity (PV) distribution is characterized
by a PV-staircase with PV-steps at the latitudes of the cores of the eastward
jets. Numerically simulated solutions to the quasigeostrophic 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. A theoretical explanation of the underlying barrier mechanism is provided. Consistent with these results,
observations of Jupiter, whose weather
layer mean flow pattern has the qualitative features of a PV-staircase flow, suggest
that both eastward and westward zonal jets serve as robust meridional
transport barriers. An alternative explanation of the mechanism by which
zonal jets act as meridional barriers, based on the notion of a PV-barrier, correctly
predicts that eastward jets act as transport barriers but incorrectly predicts
that westward jets do not.
DE: 0343 Planetary atmospheres (5210, 5405, 5704)
SC: Planetary Sciences [P]
MN: 2007 Fall Meeting