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Sea and the Gulf Stream. An increasing temperature in the Labrador Sea corresponds with
a weakening of the Gulf Stream and vice versa. A weakening of the Gulf Stream and the
North Atlantic Gyre flow implies relatively cold climate and winters in Europe. During the
cold period the NAO is low, with weak westerlies allowing the warm and salt water of the
North Atlantic current to penetrate relatively further north than during periods of strong
westerlies, coupled with a high NAO, which deviates the North Atlantic current towards
the east and south-east. Thus it seems that a relatively warmer SST period would corres-
pond with a relatively colder European period. Are the ocean and the continental temper-
atures out of phase? Can this be coupled with the strength of the westerlies? Sedimentary
records seem to indicate that an increased production of NADW is consistent with warm-
ing periods. These records suggest that the oceanic and continental climate conditions are
slightly out of phase, possibly particularly during transition periods between the climate
cycles (Guiot et al. , 1989 ) .
Multidecadal basin-wide oscillations are also well documented in other ocean regions,
in particular in the context of searching for correlations with interannual to multidecadal
fluctuations in fisheries yields. In the North Pacific Ocean, the Pacific Decadal Oscillation
(PDO) correlates with SST and sea surface height anomalies and with large-scale shifts in
North Pacific salmon production (Mantua et al ., 1997 ). A related index, the North Pacific
Gyre Oscillation (NPGO), correlates with sea surface salinity, chlorophyll a pigments, oxy-
gen, and nutrient concentrations, all indicators of planktonic foodweb productivity (Di
Lorenzo et al ., 2008 ) .
Similar oscillations have been recorded in several LMEs through studies over several
decades. An example is provided by the Yellow Sea LME, where four SST regimes have
been identified over the past 140 years: a warm period before 1900; a cold period dur-
ing 1901-1944; a warm regime with cooling trend during 1945-1976; and a warm regime
with a warming trend during 1977-2007. The SST regime shifts, fluctuations in herring
abundance and rainfall in Eastern China show good correlations (Tang, 2009 ) . These re-
gime shifts in the Yellow Sea may be coupled with multidecadal changes in the Pacific
Ocean and the related Pacific Decadal Oscillation. This has been well documented with
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