Ocean Science www.ocean-sci.net 1812-0784 1812-0792 6 1 2010 10.5194/os-6-185-2010 http://www.ocean-sci.net/6/185/2010/ http://www.ocean-sci.net/6/185/2010/os-6-185-2010.html http://www.ocean-sci.net/6/185/2010/os-6-185-2010.pdf 185 190 2010-02-08 The gyre-scale circulation of the North Atlantic and sea level at Brest P. L. Woodworth plw@pol.ac.uk N. Pouvreau G. Wöppelmann Proudman Oceanographic Laboratory, Joseph Proudman Building, 6 Brownlow Street, Liverpool L3 5DA, UK UMR 5566 LEGOS-CNES, 14 av. Edouard Belin, 31400 Toulouse, France UMR 6250 LIENSs, Université de La Rochelle – CNRS, 2 rue Olympe de Gouges, 17000 La Rochelle, France The relationship between the gyre-scale circulation of the North Atlantic, represented by air pressure near to the centre of the sub-tropical gyre, and sea level measured at the eastern boundary of the ocean has been investigated using records commencing in the middle of the 18th century. These time series are twice as long as those employed in an earlier study of this relationship. Near-continuous values of annual mean sea level and mean high water from Brest, and air pressure fields for the eastern North Atlantic derived from terrestrial instrumental pressure records and ship logbook information, have been used to demonstrate that sea level on the eastern boundary does indeed appear to be related to air pressure at the centre of the gyre (subject to reservations concerning short sub-sections of data near to the ends of the records). These findings confirm the earlier conclusions but over much longer timescales. This relationship can explain at least part of the century timescale accelerations in European sea level records obtained from tide gauge and saltmarsh data. 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