| Registro completo |
| Provedor de dados: |
ArchiMer
|
| País: |
France
|
| Título: |
Millennial-scale surface and subsurface paleothermometry from the northeast Atlantic, 55-8 ka BP
|
| Autores: |
Peck, V. L.
Hall, I. R.
Zahn, R.
Elderfield, H.
|
| Data: |
2008-09
|
| Ano: |
2008
|
| Resumo: |
We present high-resolution records of upper ocean temperatures derived from Mg/Ca ratios of surface-dwelling Globigerina bulloides and subsurface-dwelling Neogloboquadrina pachyderma sinistral and the relative abundance of N. pachyderma sinistral for the period 55-8 ka BP from NE Atlantic sediment core MD01-2461. Millennial-scale temporal variability and longer-term trends in these records enable us to develop a detailed picture of past ocean conditions such as a weakening of thermocline intensity from marine isotope stage 3 (MIS 3) to the last glacial maximum (LGM). The correspondence of all temperature proxies and convergence of paired oxygen isotope (delta O-18) records from both planktonic species implies a breakdown in the thermocline and year-round mixing of the upper water column through the LGM, perhaps related to decreasing insolation and additional cooling in association with the expansion of the circum-North Atlantic ice sheets. Millennial-scale divergence in surface and subsurface temperatures and delta O-18 across the last glacial correspond to meltwater release and the development of a strong halocline associated with both Heinrich (H) events and instabilities of the NW European ice sheet. During such episodes, G. bulloides Mg/Ca appears to record ambient, even warming summer sea surface temperatures across H events while the other proxies record maximum cooling.
|
| Tipo: |
Text
|
| Idioma: |
Inglês
|
| Identificador: |
https://archimer.ifremer.fr/doc/00237/34797/33340.pdf
DOI:10.1029/2008PA001631
https://archimer.ifremer.fr/doc/00237/34797/
|
| Editor: |
Amer Geophysical Union
|
| Formato: |
application/pdf
|
| Fonte: |
Paleoceanography (0883-8305) (Amer Geophysical Union), 2008-09 , Vol. 23 , N. 3 / PA3221 , P. 1-11
|
| Direitos: |
Copyright 2008 by the American Geophysical Union
info:eu-repo/semantics/openAccess
restricted use
|
|
