The Effect of Diapycnal Mixing on the Ventilation and CFC-11 Uptake in the Southern Ocean
The Miami Isopycnic Coordinate Ocean Model (MICOM) is used to investigate the effect of diapycnal mixing on the oceanic uptake of CFC-11 and the ventilation of the surface waters in the Southern Ocean (south of 45°S). Three model experiments are performed: one with a diapycnal mixing coefficient Kd...
Main Authors: | , |
---|---|
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Science Press
2004
|
Subjects: | |
Online Access: | https://hdl.handle.net/1956/627 |
id |
ftunivbergen:oai:bora.uib.no:1956/627 |
---|---|
record_format |
openpolar |
spelling |
ftunivbergen:oai:bora.uib.no:1956/627 2023-05-15T18:24:21+02:00 The Effect of Diapycnal Mixing on the Ventilation and CFC-11 Uptake in the Southern Ocean Gao, Yongqi Drange, Helge 2004-03-04 1771497 bytes application/pdf https://hdl.handle.net/1956/627 eng eng Science Press Advances in Atmospheric Sciences;21(5) urn:issn:0256-1530 https://hdl.handle.net/1956/627 Chlorofluorocarbons Ocean modelling Journal article 2004 ftunivbergen 2023-03-14T17:39:34Z The Miami Isopycnic Coordinate Ocean Model (MICOM) is used to investigate the effect of diapycnal mixing on the oceanic uptake of CFC-11 and the ventilation of the surface waters in the Southern Ocean (south of 45°S). Three model experiments are performed: one with a diapycnal mixing coefficient Kd (m2 s-1) of 2 • 10-7/N (Expt. 1), one with Kd = 0 (Expt. 2), and one with Kd = 5 • 10-8/N (Expt. 3), N (s-1) is the Brunt-V¨ais¨al¨a frequency. The model simulations indicate that the observed vertical distribution of CFC-11 along 88°W (prime meridian at 0°E) in the Southern Ocean is caused by local ventilation of the surface waters and westward-directed (eastward-directed) isopycnic transport and mixing from deeply ventilated waters in the Weddell Sea region. It is found that at the end of 1997, the simulated net ocean uptake of CFC-11 in Expt. 2 is 25% below that of Expt. 1. The decreased uptake of CFC-11 in the Southern Ocean accounts for 80% of this difference. Furthermore, Expts. 2 and 3 yield far more realistic vertical distributions of the ventilated CFC-waters than Expt. 1. The experiments clearly highlight the sensitivity of the Southern Ocean surface water ventilation to the distribution and thickness of the simulated mixed layer. It is argued that inclusion of CFCs in coupled climate models could be used as a test-bed for evaluating the decadal-scale ocean uptake of heat and CO2. Article in Journal/Newspaper Southern Ocean Weddell Sea University of Bergen: Bergen Open Research Archive (BORA-UiB) Southern Ocean Weddell Weddell Sea |
institution |
Open Polar |
collection |
University of Bergen: Bergen Open Research Archive (BORA-UiB) |
op_collection_id |
ftunivbergen |
language |
English |
topic |
Chlorofluorocarbons Ocean modelling |
spellingShingle |
Chlorofluorocarbons Ocean modelling Gao, Yongqi Drange, Helge The Effect of Diapycnal Mixing on the Ventilation and CFC-11 Uptake in the Southern Ocean |
topic_facet |
Chlorofluorocarbons Ocean modelling |
description |
The Miami Isopycnic Coordinate Ocean Model (MICOM) is used to investigate the effect of diapycnal mixing on the oceanic uptake of CFC-11 and the ventilation of the surface waters in the Southern Ocean (south of 45°S). Three model experiments are performed: one with a diapycnal mixing coefficient Kd (m2 s-1) of 2 • 10-7/N (Expt. 1), one with Kd = 0 (Expt. 2), and one with Kd = 5 • 10-8/N (Expt. 3), N (s-1) is the Brunt-V¨ais¨al¨a frequency. The model simulations indicate that the observed vertical distribution of CFC-11 along 88°W (prime meridian at 0°E) in the Southern Ocean is caused by local ventilation of the surface waters and westward-directed (eastward-directed) isopycnic transport and mixing from deeply ventilated waters in the Weddell Sea region. It is found that at the end of 1997, the simulated net ocean uptake of CFC-11 in Expt. 2 is 25% below that of Expt. 1. The decreased uptake of CFC-11 in the Southern Ocean accounts for 80% of this difference. Furthermore, Expts. 2 and 3 yield far more realistic vertical distributions of the ventilated CFC-waters than Expt. 1. The experiments clearly highlight the sensitivity of the Southern Ocean surface water ventilation to the distribution and thickness of the simulated mixed layer. It is argued that inclusion of CFCs in coupled climate models could be used as a test-bed for evaluating the decadal-scale ocean uptake of heat and CO2. |
format |
Article in Journal/Newspaper |
author |
Gao, Yongqi Drange, Helge |
author_facet |
Gao, Yongqi Drange, Helge |
author_sort |
Gao, Yongqi |
title |
The Effect of Diapycnal Mixing on the Ventilation and CFC-11 Uptake in the Southern Ocean |
title_short |
The Effect of Diapycnal Mixing on the Ventilation and CFC-11 Uptake in the Southern Ocean |
title_full |
The Effect of Diapycnal Mixing on the Ventilation and CFC-11 Uptake in the Southern Ocean |
title_fullStr |
The Effect of Diapycnal Mixing on the Ventilation and CFC-11 Uptake in the Southern Ocean |
title_full_unstemmed |
The Effect of Diapycnal Mixing on the Ventilation and CFC-11 Uptake in the Southern Ocean |
title_sort |
effect of diapycnal mixing on the ventilation and cfc-11 uptake in the southern ocean |
publisher |
Science Press |
publishDate |
2004 |
url |
https://hdl.handle.net/1956/627 |
geographic |
Southern Ocean Weddell Weddell Sea |
geographic_facet |
Southern Ocean Weddell Weddell Sea |
genre |
Southern Ocean Weddell Sea |
genre_facet |
Southern Ocean Weddell Sea |
op_relation |
Advances in Atmospheric Sciences;21(5) urn:issn:0256-1530 https://hdl.handle.net/1956/627 |
_version_ |
1766204790191161344 |