International Polar Year 2007–2008 - WMO

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IPY 20 07–20 08
developed or predicted in either our observations or
models during IPY. Rather than attempt the task of describing
the many dozens of IPY ecosystem projects,
mostly at an early stage, these descriptions of IPY work
take the form of regional essays focused on the Bering
Sea’, Jackie Grebmeier, the ‘Canadian Arctic shelf’,
David Barber, and ‘the Barents Sea’, Jorgen Berge and
Finlo Cottier. It is hoped that their large geographic
spread and their varied content – a flaw lead/polynya
study, an investigation of small scale ocean processes
important to large scale expected change and, what
might be termed, the more-traditional region-scale
studies of ecosystem change – will provide a representative
flavour of ecosystem science during the IPY.
Atlantic Sector
The warming of Northern Seas. The poleward
spread of extreme warmth must form an important
part of any description of the present state of arctic
and subarctic seas. The temperature and salinity of
the waters flowing into the Norwegian Sea along the
Scottish shelf and Slope have recently been at their
highest values for more than 100 years (Bill Turrell, FRS,
pers. comm., 2006). At the ‘other end’ of the inflow
path, the Report on Ocean Climate for 2006 by The
International Council for Exploration of the Sea (ICES,
2007) shows that temperatures along the Russian Kola
Section of the Barents Sea (33°30’E) have equally never
been greater in more than 100 years. Holliday et al.,
(2007) have described the continuity of the spread of
warmth along the boundary. Most recently, Polyakov
et al., (2007 and pers. comm.) have documented the
arrival of successive warm pulses at the Slope of the
Laptev Sea (Polyakov, 2005), their continued eastward
spread beyond the Novosibirskiye Islands (Polyakov et
al., 2007) and the beginnings of their offshore spread
along the Lomonosov Ridge, all neatly confirmed in
simulations using the NAOSIM model (Karcher et al.,
2007). A very similar warming has been recorded in
the Bering Sea of the Pacific sector.
Northward shift of zooplankton assemblages
in the NE Atlantic and Nordic Seas. There is an
accumulating body of evidence to suggest that many
marine ecosystems, both physically and biologically,
are responding rapidly to changes in regional climate
caused predominately by the warming of air and sea
surface temperatures (SST) and to a lesser extent by
the modification of precipitation regimes and wind
patterns. The biological manifestations of rising SST
have variously taken the form of biogeographical,
phenological, physiological and species abundance
changes. Since it is unexploited by man, the planktonic
ecosystem is a valuable index of environmental
change. From the 108 copepod taxa that it records,
the Continuous Plankton Recorder (CPR) surveys have
already identified that during the last 40 years there
has been a northward movement of warmer water
plankton by 10° latitude in the north-east Atlantic, a
similar retreat of colder water plankton to the north
and a large shift in phenology (seasonal timing) of
plankton communities of up to six weeks. The precise
mechanism is not known; SST has direct consequences
on many physiological and reproductive attributes
on marine life both directly and indirectly (e.g.
by enhancing the seasonal stability of the watercolumn
and hence nutrient availability). Equally,
the consequences of such changes on the function
and biodiversity of arctic ecosystems is at present
unknown. Nevertheless, SAHFOS (Sir Alister Hardy
Foundation for Ocean Science) has recently developed
two new statistical tools, one to measure ecosystem
stability and predict potential tipping points and
the second to model the changes of niche that may
develop under various forcing mechanisms. Using
these tools, SAHFOS intends to develop its capability
to predict the probable habitat of organisms, including
commercially important fish species, in the north-east
Atlantic and Arctic Oceans over the next century.
The CPR route network extends northwards.
To cover the temporal and geographical shifts in
the planktonic ecosystem, an agreement has been
reached between SAHFOS and the Research Council of
Norway to introduce regular CPR sampling along two
routes – the old ‘T’ route to OS M and a new route from
Tromsø to Svalbard. A next step under consideration by
SAHFOS is a possible eastwards expansion into Russian
waters where significant changes in marine production
are anticipated both from natural and anthropogenic
causes (Peter Burkhill, SAHFOS, pers. comm.).
Northward shift in the spawning location of the
arcto-Norwegian cod stock along the Norwegian
coast. Throughout the past century, though its time
of spawning has remained relatively insensitive to