Agulhas leakage predominantly responds to the southern hemisphere westerlies
The Agulhas Current plays a crucial role in the thermohaline circulation through its leakage into the South Atlantic Ocean. Under both past and present climates, the trade winds and westerlies could have the ability to modulate the amount of Indian-Atlantic inflow. Compelling arguments have been put...
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ftird:oai:ird.fr:fdi:010061255 2024-09-15T17:43:34+00:00 Agulhas leakage predominantly responds to the southern hemisphere westerlies Durgadoo, J. V. Loveday, B. R. Reason, C. J. C. /Penven, Pierrick Biastoch, A. ATLANTIQUE SUD 2013 https://www.documentation.ird.fr/hor/fdi:010061255 EN eng https://www.documentation.ird.fr/hor/fdi:010061255 oai:ird.fr:fdi:010061255 Durgadoo J. V., Loveday B. R., Reason C. J. C., Penven Pierrick, Biastoch A. Agulhas leakage predominantly responds to the southern hemisphere westerlies. 2013, 43 (10), p. 2113-2131 Boundary currents Meridional overturning circulation Wind stress Mesoscale models Numerical analysis modeling text 2013 ftird 2024-08-15T05:57:42Z The Agulhas Current plays a crucial role in the thermohaline circulation through its leakage into the South Atlantic Ocean. Under both past and present climates, the trade winds and westerlies could have the ability to modulate the amount of Indian-Atlantic inflow. Compelling arguments have been put forward suggesting that trade winds alone have little impact on the magnitude of Agulhas leakage. Here, employing three ocean models for robust analysisa global coarse-resolution, a regional eddy-permitting, and a nested high-resolution eddy-resolving configurationand systematically altering the position and intensity of the westerly wind belt in a series of sensitivity experiments, it is shown that the westerlies, in particular their intensity, control the leakage. Leakage responds proportionally to the intensity of westerlies up to a certain point. Beyond this, through the adjustment of the large-scale circulation, energetic interactions occur between the Agulhas Return Current and the Antarctic Circumpolar Current that result in a state where leakage no longer increases. This adjustment takes place within one or two decades. Contrary to previous assertions, these results further show that an equatorward (poleward) shift in westerlies increases (decreases) leakage. This occurs because of the redistribution of momentum input by the winds. It is concluded that the reported present-day leakage increase could therefore reflect an unadjusted oceanic response mainly to the strengthening westerlies over the last few decades. Text Antarc* Antarctic South Atlantic Ocean IRD (Institute de recherche pour le développement): Horizon |
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Open Polar |
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IRD (Institute de recherche pour le développement): Horizon |
op_collection_id |
ftird |
language |
English |
topic |
Boundary currents Meridional overturning circulation Wind stress Mesoscale models Numerical analysis modeling |
spellingShingle |
Boundary currents Meridional overturning circulation Wind stress Mesoscale models Numerical analysis modeling Durgadoo, J. V. Loveday, B. R. Reason, C. J. C. /Penven, Pierrick Biastoch, A. Agulhas leakage predominantly responds to the southern hemisphere westerlies |
topic_facet |
Boundary currents Meridional overturning circulation Wind stress Mesoscale models Numerical analysis modeling |
description |
The Agulhas Current plays a crucial role in the thermohaline circulation through its leakage into the South Atlantic Ocean. Under both past and present climates, the trade winds and westerlies could have the ability to modulate the amount of Indian-Atlantic inflow. Compelling arguments have been put forward suggesting that trade winds alone have little impact on the magnitude of Agulhas leakage. Here, employing three ocean models for robust analysisa global coarse-resolution, a regional eddy-permitting, and a nested high-resolution eddy-resolving configurationand systematically altering the position and intensity of the westerly wind belt in a series of sensitivity experiments, it is shown that the westerlies, in particular their intensity, control the leakage. Leakage responds proportionally to the intensity of westerlies up to a certain point. Beyond this, through the adjustment of the large-scale circulation, energetic interactions occur between the Agulhas Return Current and the Antarctic Circumpolar Current that result in a state where leakage no longer increases. This adjustment takes place within one or two decades. Contrary to previous assertions, these results further show that an equatorward (poleward) shift in westerlies increases (decreases) leakage. This occurs because of the redistribution of momentum input by the winds. It is concluded that the reported present-day leakage increase could therefore reflect an unadjusted oceanic response mainly to the strengthening westerlies over the last few decades. |
format |
Text |
author |
Durgadoo, J. V. Loveday, B. R. Reason, C. J. C. /Penven, Pierrick Biastoch, A. |
author_facet |
Durgadoo, J. V. Loveday, B. R. Reason, C. J. C. /Penven, Pierrick Biastoch, A. |
author_sort |
Durgadoo, J. V. |
title |
Agulhas leakage predominantly responds to the southern hemisphere westerlies |
title_short |
Agulhas leakage predominantly responds to the southern hemisphere westerlies |
title_full |
Agulhas leakage predominantly responds to the southern hemisphere westerlies |
title_fullStr |
Agulhas leakage predominantly responds to the southern hemisphere westerlies |
title_full_unstemmed |
Agulhas leakage predominantly responds to the southern hemisphere westerlies |
title_sort |
agulhas leakage predominantly responds to the southern hemisphere westerlies |
publishDate |
2013 |
url |
https://www.documentation.ird.fr/hor/fdi:010061255 |
op_coverage |
ATLANTIQUE SUD |
genre |
Antarc* Antarctic South Atlantic Ocean |
genre_facet |
Antarc* Antarctic South Atlantic Ocean |
op_relation |
https://www.documentation.ird.fr/hor/fdi:010061255 oai:ird.fr:fdi:010061255 Durgadoo J. V., Loveday B. R., Reason C. J. C., Penven Pierrick, Biastoch A. Agulhas leakage predominantly responds to the southern hemisphere westerlies. 2013, 43 (10), p. 2113-2131 |
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