Publication Date:
2022-05-25
Description:
Author Posting. © American Meteorological Society, 2013. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Physical Oceanography 43 (2013): 744–765, doi:10.1175/JPO-D-12-067.1.
Description:
This study investigates the coherence between ocean bottom pressure signals at the Rapid Climate Change programme (RAPID) West Atlantic Variability Experiment (WAVE) array on the western North Atlantic continental slope, including the Woods Hole Oceanographic Institution Line W. Highly coherent pressure signals propagate southwestward along the slope, at speeds in excess of 128 m s−1, consistent with expectations of barotropic Kelvin-like waves. Coherent signals are also evidenced in the smaller pressure differences relative to 1000-m depth, which are expected to be associated with depth-dependent basinwide meridional transport variations or an overturning circulation. These signals are coherent and almost in phase for all time scales from 3.6 years down to 3 months. Coherence is still seen at shorter time scales for which group delay estimates are consistent with a propagation speed of about 1 m s−1 over 990 km of continental slope but with large error bounds on the speed. This is roughly consistent with expectations for propagation of coastally trapped waves, though somewhat slower than expected. A comparison with both Eulerian currents and Lagrangian float measurements shows that the coherence is inconsistent with a propagation of signals by advection, except possibly on time scales longer than 6 months.
Description:
This work was funded by the U.K.
Natural Environment Research Council. Sofia Olhede
was supported by EPSRC Grant EP/I005250/1. Initial
observations at StationW(2001–04) were made possible
by a grant from the G. Unger Vetlesen Foundation and
support from the Woods Hole Oceanographic Institution.
Since 2004, the Line W program has been supported
by the U.S. National Science Foundation with
supplemental contribution from WHOIs Ocean and
Climate Change Institute.
Description:
2013-10-01
Keywords:
Atlantic Ocean
;
Boundary currents
;
Meridional overturning circulation
;
Pressure
;
Waves, oceanic
;
In situ oceanic observations
Repository Name:
Woods Hole Open Access Server
Type:
Article
Format:
application/pdf
