Characteristics and causes of Deep Western Boundary Current transport variability at 34.5° S during 2009-2014

The study analyzes nearly six years of data from pressure-equipped inverted echo sounders (PIESs) to determine the transport characteristics of the Deep Western Boundary Current (DWBC) at 34.5° S. It finds that the time-mean absolute geostrophic transport is -15 Sv, but the variability is extreme, with a peak-to-peak range from -89 to +50 Sv. This high level of variability, which exceeds the time mean, suggests the influence of coherent vortices or Rossby Wave-like signals.

• The time-mean absolute geostrophic transport within the DWBC layer (defined between 800–4800 dbar and longitude 51.5 to 44.5° W) is -15 Sv, where a negative value indicates southward flow.
• Volume transport exhibits significant variability, with a temporal standard deviation of 23 Sv and a peak-to-peak range spanning from -89 to +50 Sv.
• The time variability of the DWBC at 34.5° S greatly exceeds its time mean, which likely indicates the presence of Rossby Wave-like signals propagating from the interior to the boundary or strong coherent vortices.

APA

Inter-American Institute for Global Change Research (2025). Characteristics and causes of Deep Western Boundary Current transport variability at 34.5° S during 2009-2014. https://iai.int/es/pub_acad/characteristics-and-causes-of-deep-western-boundary-current-transport-variability-at-34-5-s-during-2009-2014/

Chicago

Inter-American Institute for Global Change Research. Characteristics and causes of Deep Western Boundary Current transport variability at 34.5° S during 2009-2014. 2025. https://iai.int/es/pub_acad/characteristics-and-causes-of-deep-western-boundary-current-transport-variability-at-34-5-s-during-2009-2014/.

Wikipedia

{{cite report |author=Inter-American Institute for Global Change Research |title=Characteristics and causes of Deep Western Boundary Current transport variability at 34.5° S during 2009-2014 |date=13 January 2025 |url=https://iai.int/es/pub_acad/characteristics-and-causes-of-deep-western-boundary-current-transport-variability-at-34-5-s-during-2009-2014/ |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{interamericaninstituteforglobalchangeresearch2025characteristics, author = {{Inter-American Institute for Global Change Research}}, title = {{Characteristics and causes of Deep Western Boundary Current transport variability at 34.5° S during 2009-2014}}, institution = {Inter-American Institute for Global Change Research}, year = {2025}, month = jan, url = {https://iai.int/es/pub_acad/characteristics-and-causes-of-deep-western-boundary-current-transport-variability-at-34-5-s-during-2009-2014/}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }