| Full text | |
| Author(s): |
Total Authors: 3
|
| Affiliation: | [1] Univ Bremen, MARUM Ctr Marine Environm Sci, DE-28359 Bremen - Germany
[2] Univ Sao Paulo, Escola Artes Ciencias & Humanidades, Sao Paulo - Brazil
Total Affiliations: 2
|
| Document type: | Journal article |
| Source: | PALEOCEANOGRAPHY; v. 28, n. 3, p. 481-490, SEP 2013. |
| Web of Science Citations: | 12 |
| Abstract | |
Over the Uruguayan shelf and uppermost slope, the coalescence of northward flowing Subantarctic Shelf Water and southward flowing Subtropical Shelf Water forms a distinct thermohaline front termed the Subtropical Shelf Front (STSF). Running in a SW direction diagonally across the shelf from the coastal waters at 32 degrees S toward the shelf break at ca. 36 degrees S, the STSF represents the shelfward extension of the Brazil-Malvinas Confluence zone. This study reconstructs latitudinal STSF shifts during the Holocene based on benthic foraminifera O-18 and C-13, total organic carbon, carbonate contents, Ti/Ca, and grain size distribution from a high-accumulation sedimentary record located at an uppermost continental-slope terrace. Our data provide direct evidence for: (1) a southern STSF position (to the South of the core site) at the beginning of the early Holocene (>9.4calka BP) linked to a more southerly position of the Southern Westerly Winds in combination with restricted shelf circulation intensity due to lower sea level; (2) a gradual STSF northward migration (bypassing the core site toward the North) primarily forced by the northward migration of the Southern Westerly Winds from 9.4calka BP onward; (3) a relatively stable position of the front in the interval between 7.2 and 4.0calka BP; (4) millennial-scale latitudinal oscillations close to 36 degrees S of the STSF after 4.0calka BP probably linked to the intensification in El Nino Southern Oscillation; and (5) a southward migration of the STSF during the last 200years possibly linked to anthropogenic influences on the atmosphere. (AU) | |
| FAPESP's process: | 12/17517-3 - Response of the Western Atlantic Ocean to changes in the Atlantic meridional overturning circulation: from millennial to seasonal variability |
| Grantee: | Cristiano Mazur Chiessi |
| Support type: | Research Program on Global Climate Change - Young Investigators |
| FAPESP's process: | 11/50394-0 - Variability of the South American monsoon system of the last three millennia integrating lake, speleothem and marine records |
| Grantee: | Francisco William da Cruz Junior |
| Support type: | Research Program on Global Climate Change - Regular Grants |
| FAPESP's process: | 10/09983-9 - Sea surface temperature changes in the western South Atlantic and precipitation variability in southeastern South America since the Last Glacial Maximum |
| Grantee: | Cristiano Mazur Chiessi |
| Support type: | Regular Research Grants |