摘要:Ocean climate, environmental and biological conditions vary on several spatio-temporal scales.
Besides climate change associated with anthropogenic activity, there is growing evidence of
a natural global multi-decadal climate signal in the ocean–atmosphere–biosphere climate
system. The spatio-temporal evolution of this signal is thus analyzed during the 20th
century and compared to the variability of small-pelagic fish landings. It is argued that the
low-frequency global ocean environment and plankton ecosystems must be modified such
that small-pelagic populations vary accordingly. A small-pelagic global index or fishing
'regime indicator series' (RIS) (i.e. a small-pelagic abundance indicator) is used. RIS is
derived from fish landings data in the four main fishing areas in the Pacific and Atlantic
oceans. Global RIS changes phase (from positive to negative values) when SST
multi-decadal anomalies are out-of-phase between the eastern Pacific and southern
Atlantic. RIS also displays maxima during the mid-30s to early-40s and the late-70s to
early-80s when the multi-decadal signal was approximately changing phases (Tourre and
White 2006 Geophys. Res. Lett.33 L06716). It is recognized that other factors may
modulate fish stocks, including anthropogenic predation. Nevertheless it is proposed that
variable climate and environment, and the low-frequency 'global synchrony' of
small-pelagic landings (Schwartzlose et al 1999 S. Afr. J. Mar. Sci.21 289–347), could be
associated with the multi-decadal changes in global ocean climate conditions.