Observations of the vertical and temporal evolution of a Natal Pulse along the Eastern Agulhas Bank
Copyright: 2016 American Geophysical Union This study reinvestigates the work of Lutjeharms et al. (2001, 2003) who documented the properties of a Natal Pulse using isopycnal Lagrangian floats. We combined Lagrangian analyses and Eulerian maps derived from objective analysis to better describe the e...
Main Authors: | , , |
---|---|
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
American Geophysical Union
2016
|
Subjects: | |
Online Access: | http://hdl.handle.net/10204/9383 http://onlinelibrary.wiley.com/doi/10.1002/2015JC011582/abstract |
id |
ftcsir:oai:researchspace.csir.co.za:10204/9383 |
---|---|
record_format |
openpolar |
spelling |
ftcsir:oai:researchspace.csir.co.za:10204/9383 2023-05-15T14:03:01+02:00 Observations of the vertical and temporal evolution of a Natal Pulse along the Eastern Agulhas Bank Pivan, X Krug, Marjolaine J Herbette, S 2016-09 application/pdf http://hdl.handle.net/10204/9383 http://onlinelibrary.wiley.com/doi/10.1002/2015JC011582/abstract en eng American Geophysical Union Workflow;18548 Workflow;18618 Pivan, X., Krug, M.J. and Herbette, S. 2016. Observations of the vertical and temporal evolution of a Natal Pulse along the Eastern Agulhas Bank. Journal of Geophysical Research: Oceans, 121(9), pp 7108-7122 2169-9275 http://onlinelibrary.wiley.com/doi/10.1002/2015JC011582/abstract http://hdl.handle.net/10204/9383 Pivan, X., Krug, M. J., & Herbette, S. (2016). Observations of the vertical and temporal evolution of a Natal Pulse along the Eastern Agulhas Bank. http://hdl.handle.net/10204/9383 Pivan, X, Marjolaine J Krug, and S Herbette "Observations of the vertical and temporal evolution of a Natal Pulse along the Eastern Agulhas Bank." (2016) http://hdl.handle.net/10204/9383 Pivan X, Krug MJ, Herbette S. Observations of the vertical and temporal evolution of a Natal Pulse along the Eastern Agulhas Bank. 2016; http://hdl.handle.net/10204/9383. Geophysics Natal pulse Eastern Agulhas Bank Article 2016 ftcsir 2022-05-19T06:12:00Z Copyright: 2016 American Geophysical Union This study reinvestigates the work of Lutjeharms et al. (2001, 2003) who documented the properties of a Natal Pulse using isopycnal Lagrangian floats. We combined Lagrangian analyses and Eulerian maps derived from objective analysis to better describe the evolution of a Natal Pulse along three density surfaces referred to as the surface (satellite-observed), shallow (isopycnal 1026.8 kg m-3), and deep (isopycnal 1027.2 kg m-3) layer. Our observations show that this Natal Pulse extended to a depth of 1000 m and was associated with cyclonic relative vorticity values of about 6.5–8.5 × 10-5 s-1 in the surface and shallow layer and 4 × 10-5 s-1 in the deep layer. This Natal Pulse contributed to cross-shelf exchange through the offshore advection of Eastern Agulhas Bank water near the surface, onshore advection of South Indian Central Water and/or Indian Equatorial Water in the shallow layer, and Antarctic Intermediate Water in the deep layer. Sea surface temperature maps showed that the downstream progression of the Natal Pulse along the 3000 m isobath was related to a readjustment of its rotation axis. This readjustment advected Eastern Agulhas Bank water into the Natal Pulse eddy and triggered a SST cooling of about 3°C in the cyclonic area. The importance of a warm recirculating Agulhas plume originating from the Natal Pulse was highlighted. This warm water plume extended to a depth of 700 m and was associated with onshore velocities exceeding those experienced within the Natal Pulse eddy by a factor of 2. Our observations indicate that the June/July 1998 Natal Pulse and its associated plumes enhanced cross-shelf exchanges. Article in Journal/Newspaper Antarc* Antarctic Council for Scientific and Industrial Research (South Africa): CSIR Research Space Antarctic Indian |
institution |
Open Polar |
collection |
Council for Scientific and Industrial Research (South Africa): CSIR Research Space |
op_collection_id |
ftcsir |
language |
English |
topic |
Geophysics Natal pulse Eastern Agulhas Bank |
spellingShingle |
Geophysics Natal pulse Eastern Agulhas Bank Pivan, X Krug, Marjolaine J Herbette, S Observations of the vertical and temporal evolution of a Natal Pulse along the Eastern Agulhas Bank |
topic_facet |
Geophysics Natal pulse Eastern Agulhas Bank |
description |
Copyright: 2016 American Geophysical Union This study reinvestigates the work of Lutjeharms et al. (2001, 2003) who documented the properties of a Natal Pulse using isopycnal Lagrangian floats. We combined Lagrangian analyses and Eulerian maps derived from objective analysis to better describe the evolution of a Natal Pulse along three density surfaces referred to as the surface (satellite-observed), shallow (isopycnal 1026.8 kg m-3), and deep (isopycnal 1027.2 kg m-3) layer. Our observations show that this Natal Pulse extended to a depth of 1000 m and was associated with cyclonic relative vorticity values of about 6.5–8.5 × 10-5 s-1 in the surface and shallow layer and 4 × 10-5 s-1 in the deep layer. This Natal Pulse contributed to cross-shelf exchange through the offshore advection of Eastern Agulhas Bank water near the surface, onshore advection of South Indian Central Water and/or Indian Equatorial Water in the shallow layer, and Antarctic Intermediate Water in the deep layer. Sea surface temperature maps showed that the downstream progression of the Natal Pulse along the 3000 m isobath was related to a readjustment of its rotation axis. This readjustment advected Eastern Agulhas Bank water into the Natal Pulse eddy and triggered a SST cooling of about 3°C in the cyclonic area. The importance of a warm recirculating Agulhas plume originating from the Natal Pulse was highlighted. This warm water plume extended to a depth of 700 m and was associated with onshore velocities exceeding those experienced within the Natal Pulse eddy by a factor of 2. Our observations indicate that the June/July 1998 Natal Pulse and its associated plumes enhanced cross-shelf exchanges. |
format |
Article in Journal/Newspaper |
author |
Pivan, X Krug, Marjolaine J Herbette, S |
author_facet |
Pivan, X Krug, Marjolaine J Herbette, S |
author_sort |
Pivan, X |
title |
Observations of the vertical and temporal evolution of a Natal Pulse along the Eastern Agulhas Bank |
title_short |
Observations of the vertical and temporal evolution of a Natal Pulse along the Eastern Agulhas Bank |
title_full |
Observations of the vertical and temporal evolution of a Natal Pulse along the Eastern Agulhas Bank |
title_fullStr |
Observations of the vertical and temporal evolution of a Natal Pulse along the Eastern Agulhas Bank |
title_full_unstemmed |
Observations of the vertical and temporal evolution of a Natal Pulse along the Eastern Agulhas Bank |
title_sort |
observations of the vertical and temporal evolution of a natal pulse along the eastern agulhas bank |
publisher |
American Geophysical Union |
publishDate |
2016 |
url |
http://hdl.handle.net/10204/9383 http://onlinelibrary.wiley.com/doi/10.1002/2015JC011582/abstract |
geographic |
Antarctic Indian |
geographic_facet |
Antarctic Indian |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_relation |
Workflow;18548 Workflow;18618 Pivan, X., Krug, M.J. and Herbette, S. 2016. Observations of the vertical and temporal evolution of a Natal Pulse along the Eastern Agulhas Bank. Journal of Geophysical Research: Oceans, 121(9), pp 7108-7122 2169-9275 http://onlinelibrary.wiley.com/doi/10.1002/2015JC011582/abstract http://hdl.handle.net/10204/9383 Pivan, X., Krug, M. J., & Herbette, S. (2016). Observations of the vertical and temporal evolution of a Natal Pulse along the Eastern Agulhas Bank. http://hdl.handle.net/10204/9383 Pivan, X, Marjolaine J Krug, and S Herbette "Observations of the vertical and temporal evolution of a Natal Pulse along the Eastern Agulhas Bank." (2016) http://hdl.handle.net/10204/9383 Pivan X, Krug MJ, Herbette S. Observations of the vertical and temporal evolution of a Natal Pulse along the Eastern Agulhas Bank. 2016; http://hdl.handle.net/10204/9383. |
_version_ |
1766273466515849216 |