DIMES: Diapycnal and Isopycnal Mixing Experiment in the Southern Ocean
Lead Research Organisation:
British Antarctic Survey
Department Name: Science Programmes
Abstract
Detailed in Lead Institution (NOC) Proposal
Organisations
Publications
Mackay N
(2018)
Diapycnal Mixing in the Southern Ocean Diagnosed Using the DIMES Tracer and Realistic Velocity Fields
in Journal of Geophysical Research: Oceans
Mashayek A
(2017)
Topographic enhancement of vertical turbulent mixing in the Southern Ocean.
in Nature communications
Meijers A
(2016)
Wind-driven export of W eddell S ea slope water
in Journal of Geophysical Research: Oceans
Meredith M
(2013)
Dense bottom layers in the Scotia Sea, Southern Ocean: Creation, lifespan, and destruction
in Geophysical Research Letters
Meredith M
(2011)
SUSTAINED MONITORING OF THE SOUTHERN OCEAN AT DRAKE PASSAGE: PAST ACHIEVEMENTS AND FUTURE PRIORITIES
in Reviews of Geophysics
Meredith M
(2012)
Sensitivity of the Overturning Circulation in the Southern Ocean to Decadal Changes in Wind Forcing
in Journal of Climate
Meredith M
(2015)
Circulation, retention, and mixing of waters within the W eddell- S cotia C onfluence, S outhern O cean: The role of stratified T aylor columns
in Journal of Geophysical Research: Oceans
Naveira Garabato AC
(2019)
Rapid mixing and exchange of deep-ocean waters in an abyssal boundary current.
in Proceedings of the National Academy of Sciences of the United States of America
Naveira Garabato AC
(2017)
High-latitude ocean ventilation and its role in Earth's climate transitions.
in Philosophical transactions. Series A, Mathematical, physical, and engineering sciences
Description | Controls on the spreading and mixing of dense waters from Antarctica Deep mixing in the Southern Ocean is an important process in closing the lower limb of the oceanic overturning circulation, with implications for deep ocean ventilation and global climate. Several years of ship-based measurements in the Scotia Sea (Southern Ocean) were analysed, and the episodic presence of very dense layers at the seabed was discovered. These layers had vertical gradients in temperature and density that are as strong as those in the near-surface Southern Ocean, and are caused by water intermittently spilling across a ridge at the entrance to the Scotia Sea and becoming trapped in deep trenches. Using measurements of dissolved tracers, one such layer was found to have been trapped for at least 3-4 years. This enabled vertical mixing to be calculated, and it was found that the rate of mixing that the layer had been subjected to was substantially less than the very strong basin-average mixing reported previously. It was concluded that deep mixing in the Scotia Sea is significantly spatially structured, with the majority of the mixing occurring as the water crosses the ridge to enter the basin. Similar layers are observed outside the Scotia Sea, indicating that the same controls on the spreading and mixing of deep ocean waters may be widespread. |
Exploitation Route | See NE/E007058/1 |
Sectors | Environment |
Description | See NE/E007058/1 |
First Year Of Impact | 2010 |
Sector | Other |