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| Hall, I. R.; Boessenkool, K. P.; Barker, S.; Mccave, I. N.; Elderfield, H.. |
| The subpolar North Atlantic Ocean (SPNA) is of key importance for modulating the climate of NW Europe because of heat loss to the atmosphere from the North Atlantic Current. Although hydrographic properties of the surface SPNA vary on interannual to multidecadal timescales, hydrographic time series scarcely extend back beyond the 1950s. We present a 230 year long record of SPNA surface conditions reconstructed from a very high accumulation rate core that also registers changes in deep flow speed in the Iceland Basin. A lagged correlation is observed between the records of deep flow speed and stable oxygen isotopic composition of the surface SPNA (delta(18)O(w)), with strongest correlation when the paleoflow speed record leads by 15-20 years. This offset... |
| Tipo: Text |
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| Ano: 2010 |
URL: https://archimer.ifremer.fr/doc/00231/34203/32762.pdf |
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| Boessenkool, K. P.; Hall, I. R.; Elderfield, H.; Yashayaev, I.. |
| Variations in the near-bottom flow speed of Iceland-Scotland Overflow Water (ISOW) are documented in a 230-year-long deep-sea sediment record from the eastern flank of Reykjanes Ridge in the subpolar North Atlantic at (sub) decadal time scales. For recent decades, the ISOW palaeocurrent reconstructions show similarities with observational hydrographic data. Furthermore, recent ISOW flow changes fall mostly within the range of its variability of the past 230 years. The record also reveals a hitherto unrecognized coupling of deep flow speeds in the subpolar North Atlantic with the North Atlantic Oscillation (NAO) index, with more (less) vigorous ISOW flow during negative (positive) phases of the NAO. Our results suggest that the changes in ISOW vigor are... |
| Tipo: Text |
Palavras-chave: Deep ocean circulation; North Atlantic Oscillation; Drift sediments. |
| Ano: 2007 |
URL: https://archimer.ifremer.fr/doc/00235/34646/33007.pdf |
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