Long-period changes in the bottom water fLowing through Vema Channel

Further details of the “warming” of bottom water flowing through the Vema Channel, first reported by Zenk and Hogg [1996], are given. Because cross‐channel gradients of temperature are large and the channel is narrow, careful analysis is required to determine whether or not the bottom water temperat...

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Bibliographic Details
Published in:Journal of Geophysical Research: Oceans
Main Authors: Hogg, N., Zenk, Walter
Format: Article in Journal/Newspaper
Language:English
Published: AGU (American Geophysical Union) 1997
Subjects:
Online Access:https://oceanrep.geomar.de/id/eprint/1988/
https://oceanrep.geomar.de/id/eprint/1988/1/Hogg_et_al-1997-Journal_of_Geophysical_Research__Oceans_%281978-2012%29.pdf
https://doi.org/10.1029/97JC00591
Description
Summary:Further details of the “warming” of bottom water flowing through the Vema Channel, first reported by Zenk and Hogg [1996], are given. Because cross‐channel gradients of temperature are large and the channel is narrow, careful analysis is required to determine whether or not the bottom water temperature minimum was adequately sampled by a particular station or cruise. During a period from 1972 to 1996, at least 14 visits with quality hydrographic measurements have been made to the region. Of these, 11 were judged successful, and their data indicate an abrupt rise in potential temperature by 0.03°C from −0.18°C to −0.15°C in the early 1990s that has remained until the latest observation in the spring of 1996. Although this observation is consistent with the report of warming of Antarctic Bottom Water in the Argentine Basin by Coles et al [1996], their associated conclusion that this water mass has also freshened by 0.008 psu (on potential density surfaces) is in contradiction with our finding of no measurable change.