HR: 14:00h
AN: OS52K-01 [PDF]
TI: Scale Interactions in the Tropical Pacific: The Role of Lateral Mixing
AU: * Richards, K J
EM: rkelvin@hawaii.edu
AF: IPRC/SOEST
University of Hawaii, 1680 East West Road, Honolulu, HI 96816
United States
AB:
The extent to which scale interactions affect the evolution of the tropical Pacific ocean and atmosphere system on basin-wide
and inter-annual space and time scales is still an open question. One possible mechanism we investigate here is the linking
of inter-annual variations of the system and lateral mixing within the thermocline. The link is the instability of the time
varying zonal current system. Analysis of archived ADCP data shows the flow is potentially unstable to inertial instability
for periods that are modulated on interannual timescales. Inertial instability will cause lateral motions that are consistent
with the observed interleaving of water masses within the thermocline of the equatorial Pacific. The interleaving is
responsible for significant amounts of lateral mixing of both tracers and momentum and is itself modulated on interannual
timescales. Numerical experimentation demonstrates that this mixing will feedback to the current and thermal structure of the
ocean. Ways of including the the enhanced mixing in ocean GCMs and climate models will be discussed.
DE: 4231 Equatorial oceanography
DE: 4522 El Ni¤o
DE: 4568 Turbulence, diffusion, and mixing processes
SC: Ocean Sciences [OS]
MN: 2004 Ocean Sciences Meeting