Finite dispersal of a separative nepheloid plume by an internal hydraulic jump in a tropical mountainous river estuary

There are no files associated with this record.

Title Finite dispersal of a separative nepheloid plume by an internal hydraulic jump in a tropical mountainous river estuary
Author Wu, Jiaxue; Ametistova, Lioudmila; Heron, Malcolm; Lemckert, Charles James; Kalangi, Patrice
Journal Name Journal of Geophysical Research
Year Published 2006
Place of publication USA
Publisher American Geophysical Union
Abstract This paper investigates the dynamics of an internal hydraulic jump in a river plume and associated suspended sediment dispersal. Field investigations were undertaken into the river plume generated by the Herbert River, Australia, following a moderate flood event induced by Cyclone Fritz in 2004. The forced plume experiences an abrupt transition from supercritical to subcritical via an internal hydraulic jump, as defined by a mode-1 internal Froude number computed using the phase speeds from the Taylor- Goldstein equation. The hydraulic theory of a two-layer stratified flow was used to identify the plume shape and the mechanical energy loss within the jump. The hydraulic jump energy loss is primarily transferred to the buoyancy-driven potential energy, uplifting the river plume. Intense stratification decreases the bottom stress, damping the resuspension. Therefore, a separative nepheloid dispersal system occurs at the jump section. Both the upper and lower nepheloid flows are confined to the inner shelf, but have different dispersal behaviors and mechanisms. The upper nepheloid flow, which is primarily controlled by advection and settling, satisfies an exponential decay law of the total suspended sediment concentrations versus the offshore distance. The lower nepheloid flow dominated by deposition is detached seaward near the lift-off point of the river plume. A turbidity front associated with the jump may accumulate a large quantity of suspended sediments, enhancing sediment release from the river plume. These findings will promote in-depth understanding of both the cross-shelf sediment dispersal and muddy deposit on the shelf.
Peer Reviewed Yes
Published Yes
Publisher URI http://www.agu.org/pubs/
Alternative URI http://dx.doi.org/10.1029/2005JC003404
Copyright Statement Copyright 2006 American Geophysical Union. Please refer to the journal link for access to the definitive, published version.
Volume 111
Page from 1
Page to 20
ISSN 0148-0227
Date Accessioned 2007-02-22
Date Available 2009-09-02T07:43:02Z
Language en_AU
Faculty Faculty of Science, Environment, Engineering and Technology
Subject PRE2009-Physical Oceanography
URI http://hdl.handle.net/10072/14427
Publication Type Journal Articles (Refereed Article)
Publication Type Code c1

Show simple item record

Griffith University copyright notice