Detail of the thermal structure of oceanic fronts in the Southern ocean south of Africa
| dc.contributor.advisor | Lutjeharms, Johann | |
| dc.contributor.author | Matthysen, Craig Peter | |
| dc.date.accessioned | 2020-05-12T11:48:42Z | |
| dc.date.available | 2020-05-12T11:48:42Z | |
| dc.date.issued | 1997 | |
| dc.date.updated | 2020-04-02T11:21:12Z | |
| dc.description.abstract | This investigation addresses the thermal characteristics of the major oceanic frontal systems in the Southern Ocean south of Africa based on data collected to a depth of 500 m on forty-three cruises during a fifteen year period. The width of the Agulhas Front has been shown to vary considerably in both its sea surface and sub-surface thermal manifestation as a result of mesoscale turbulence. Its mean sea surface width of 84 km has a standard deviation of 53 km, and the mean subsurface width of 37 km has a standard deviation of 33 km. The Agulhas Front. has been found to be a separate front north of the Subtropical Convergence in 56 % of the cruises investigated. It has only been observed from 18,2°E to 24,7°E, with a mean sea and subsurface temperature gradient across the Agulhas Front of 0,05 °C/km and 0, 13 °C/km respectively. It has a mean sea surface middle temperature of 17, 8° C and a mean subsurface middle temperature of 12,6° C. The mean sea and sub-surface geographic positions of the thermal expression of the Agulhas Front are 39,3° S; 22,7° E aild 39,1° S; 22,7° E. The Subtropical Convergence at surface has been found to be a single, broad frontal zone across the Central/South East Atlantic Ocean, that does not bifurcate. It has a mean sea surface middle temperature of ·14,3° C and a mean sub-surface middle temperature of 8,4° C. The mean sea and sub-surface temperature gradients across the Subtropical Convergence are O, 03 °C/km and O, 05 °C/km respectively. The mean sea and sub-surface geographic positions of the· thermal expression of the Subtropical Convergence are 41, 8° S; 21, 9° E and 41, 7° S; 22, 0° E. The Subtropical Convergence has a mean sea surface width of 146 km and a mean sub-surface width of 79 km. The Sub-antarctic Front is pressed northward from 45° S to 43° S by the Mid-Ocean Ridge in the South West Indian Ocean sector, after which it converges · with the Subtropical Convergence at approximately 60° E to form a united STC/SAF at subsurface. This united STC/SAF does not however form a "Crozet Front" by joining the Agulhas Front between 52° E and 65° E. It has a mean sea surface middle temperature of 4,4° C and a mean sub-surface middle temperature of 4,0° C. The mean sea and subsurface temperature gradients across the Sub-antarctic Front are 0,02 °C/km. The mean sea and sub-surface geographic positions of the thermal expression of the Sub-antarctic Front are 48,7° S; 18,9° E and 46,8° S; 19,9° E. The Sub-antarctic Front has a mean sea surface width of 73 km and a mean sub-surface width of 77 km. In 30 % of the sections investigated the- Antarctic Polar Front consisted of a primary and secondary front. The Antarctic Polar Front does not join the Sub-antarctic Front east of · 40° E at sub-surface and subsequently no quadruple front is formed. It has a mean sea surface middle temperature of 2, 1 ° C and a mean sub-surface middle temperature of 2,3° C. The mean sea and sub-surface temperature gradients across the Antarctic Polar Front are 0,01 °C/km and 0,02 °C/km respectively. The mean sea and sub-surface geographic position of the thermal expression of the Antarctic Polar Front are 52, 7° S; 14,9° E and 49,2° S; 20,8° E. The Antarctic Polar Front has a mean sea surface width of 66 km and a mean sub-surface width of 74 km. | |
| dc.identifier.apacitation | Matthysen, C. P. (1997). <i>Detail of the thermal structure of oceanic fronts in the Southern ocean south of Africa</i>. (). ,Faculty of Science ,Department of Oceanography. Retrieved from | en_ZA |
| dc.identifier.chicagocitation | Matthysen, Craig Peter. <i>"Detail of the thermal structure of oceanic fronts in the Southern ocean south of Africa."</i> ., ,Faculty of Science ,Department of Oceanography, 1997. | en_ZA |
| dc.identifier.citation | Matthysen, C.P. 1997. Detail of the thermal structure of oceanic fronts in the Southern ocean south of Africa. . ,Faculty of Science ,Department of Oceanography. | en_ZA |
| dc.identifier.ris | TY - Thesis / Dissertation AU - Matthysen, Craig Peter AB - This investigation addresses the thermal characteristics of the major oceanic frontal systems in the Southern Ocean south of Africa based on data collected to a depth of 500 m on forty-three cruises during a fifteen year period. The width of the Agulhas Front has been shown to vary considerably in both its sea surface and sub-surface thermal manifestation as a result of mesoscale turbulence. Its mean sea surface width of 84 km has a standard deviation of 53 km, and the mean subsurface width of 37 km has a standard deviation of 33 km. The Agulhas Front. has been found to be a separate front north of the Subtropical Convergence in 56 % of the cruises investigated. It has only been observed from 18,2°E to 24,7°E, with a mean sea and subsurface temperature gradient across the Agulhas Front of 0,05 °C/km and 0, 13 °C/km respectively. It has a mean sea surface middle temperature of 17, 8° C and a mean subsurface middle temperature of 12,6° C. The mean sea and sub-surface geographic positions of the thermal expression of the Agulhas Front are 39,3° S; 22,7° E aild 39,1° S; 22,7° E. The Subtropical Convergence at surface has been found to be a single, broad frontal zone across the Central/South East Atlantic Ocean, that does not bifurcate. It has a mean sea surface middle temperature of ·14,3° C and a mean sub-surface middle temperature of 8,4° C. The mean sea and sub-surface temperature gradients across the Subtropical Convergence are O, 03 °C/km and O, 05 °C/km respectively. The mean sea and sub-surface geographic positions of the· thermal expression of the Subtropical Convergence are 41, 8° S; 21, 9° E and 41, 7° S; 22, 0° E. The Subtropical Convergence has a mean sea surface width of 146 km and a mean sub-surface width of 79 km. The Sub-antarctic Front is pressed northward from 45° S to 43° S by the Mid-Ocean Ridge in the South West Indian Ocean sector, after which it converges · with the Subtropical Convergence at approximately 60° E to form a united STC/SAF at subsurface. This united STC/SAF does not however form a "Crozet Front" by joining the Agulhas Front between 52° E and 65° E. It has a mean sea surface middle temperature of 4,4° C and a mean sub-surface middle temperature of 4,0° C. The mean sea and subsurface temperature gradients across the Sub-antarctic Front are 0,02 °C/km. The mean sea and sub-surface geographic positions of the thermal expression of the Sub-antarctic Front are 48,7° S; 18,9° E and 46,8° S; 19,9° E. The Sub-antarctic Front has a mean sea surface width of 73 km and a mean sub-surface width of 77 km. In 30 % of the sections investigated the- Antarctic Polar Front consisted of a primary and secondary front. The Antarctic Polar Front does not join the Sub-antarctic Front east of · 40° E at sub-surface and subsequently no quadruple front is formed. It has a mean sea surface middle temperature of 2, 1 ° C and a mean sub-surface middle temperature of 2,3° C. The mean sea and sub-surface temperature gradients across the Antarctic Polar Front are 0,01 °C/km and 0,02 °C/km respectively. The mean sea and sub-surface geographic position of the thermal expression of the Antarctic Polar Front are 52, 7° S; 14,9° E and 49,2° S; 20,8° E. The Antarctic Polar Front has a mean sea surface width of 66 km and a mean sub-surface width of 74 km. DA - 1997 DB - OpenUCT DP - University of Cape Town KW - thermal characteristics KW - oceanic frontal systems LK - https://open.uct.ac.za PY - 1997 T1 - Detail of the thermal structure of oceanic fronts in the Southern ocean south of Africa TI - Detail of the thermal structure of oceanic fronts in the Southern ocean south of Africa UR - ER - | en_ZA |
| dc.identifier.uri | https://hdl.handle.net/11427/31853 | |
| dc.identifier.vancouvercitation | Matthysen CP. Detail of the thermal structure of oceanic fronts in the Southern ocean south of Africa. []. ,Faculty of Science ,Department of Oceanography, 1997 [cited yyyy month dd]. Available from: | en_ZA |
| dc.language.rfc3066 | eng | |
| dc.publisher.department | Department of Oceanography | |
| dc.publisher.faculty | Faculty of Science | |
| dc.subject | thermal characteristics | |
| dc.subject | oceanic frontal systems | |
| dc.title | Detail of the thermal structure of oceanic fronts in the Southern ocean south of Africa | |
| dc.type | Master Thesis | |
| dc.type.qualificationlevel | Masters |