International Polar Year 2007–2008 - WMO

array for the identification and consistent monitoring
of biophysical responses in pivotal geographic areas
that exhibit high productivity, biodiversity and rates of
change. The proposed regions are the: 1) northern Bering
Sea, 2) Bering Strait/SE Chukchi Sea, 3) Central Chukchi
Sea and 4) Barrow Arc. Stations in these regions can
be visited through an international network of ship operations,
both ongoing and planned. These include Canadian,
Chinese, Japanese, Korean, Russian and U.S.A.
research vessels coordinated through the international
Pacific Arctic Group (PAG), and land based research
from coastal communities using helicopter and small
ships. A suite of primary standard station measurements
are proposed for each of the DBO stations to be
occupied by multiple international ships and dedicated
national programs. Core hydrographic (T, S, chlorophyll,
nutrients) and biological measurements (faunal diversity,
abundance and biomass) of lower trophic level
prey (zooplankton and benthic fauna) coincident with
high trophic predators (seabirds, fish and marine mammals)
would be the foci measurements. A second tier of
sampling would include fishery acoustics and bottom
trawling surveys on a more limited basis. Multidisciplinary
moorings and satellite observations at focused
regional locations would also be encouraged. The DBO
would leverage ongoing and planned programs, both
domestic and international. Incorporation of the DBO
concept within the development of the international
Sustaining Arctic Observing Networks (SAON) process
(Chapter 3.8) will provide a foundation for investing system-level
biological response to Arctic climate change
and for improving the linkage between communitybased
monitoring and science-based measurement. An
international community-developed plan of time series
transects and stations for biodiversity studies of lower
to higher trophic levels is being proposed in a pan-
Arctic mode as part of the Arctic Council’s Circumpolar
Biodiversity Monitoring Program (CBMP; http://cbmp.
arcticportal.org/).
The Arctic Deep Basins: what questions
should we be testing?
Until relatively recently, the Arctic Deep Basins were
among the least-measured places in the World Ocean.
All that has now changed. The WHOI Beaufort Gyre
Exploration Project [later Beaufort Gyre Observing
System (BGOS)], led by Andrey Proshutinsky and
employing a suite of new observing techniques has,
since 2003, gradually transformed the data desert of
the Beaufort Gyre into what is now one of the bestcovered
regions of our northern seas. The elaboration
of that effort into a BGOS/C3O/JOIS collaboration
and the intensive survey of its borderlands by
other collaborative ventures such as JWACS (Joint
Western Arctic Climate Studies between JAMSTEC
and Canada DFO/IOS since 2002) and CHINARE (the
Chinese National Arctic Research Expedition with EC-
DAMOCLES aboard icebreaker “Xue Long” in 2008)
have continued to intensify the scientific focus on the
Beaufort Gyre, Canada Basin and Chukchi Sea so that
our ideas of what drives change throughout this region
and the significance of these changes for climate have
developed rapidly. As a result, we now regard the
Beaufort Gyre-Canada Basin as ‘The Flywheel of the
Arctic Climate’ (the subtitle of the WHOI BGOS project)
and as one of the key sites in the World Ocean from the
viewpoint of the Ocean’s role in climate.
Q: What is the role of the Beaufort Gyre as a variable
freshwater source/ reservoir?
A: As the world warms, the expectation is that the
freshwater outflows from the Arctic Ocean to the
North Atlantic will strengthen and may suppress the
rate of the climatically important Atlantic meridional
overturning circulation. For some time, we have been
aware in general terms of the link between retention/
release of freshwater from the Gyre and the state of
the Arctic Oscillation. But it was relatively recently that
the Beaufort Gyre has been identified as the largest
marine reservoir of freshwater on Earth (Carmack et
al., 2008) and the WHOI BGOS data have elaborated
the details of the state, variability and controls on
its freshwater content (FWC). The major cause of the
large FWC in the Canada Basin is now recognised to
be the process of Ekman pumping generated by the
climatological anticyclonic atmospheric circulation
centered on the Beaufort Gyre (Proshutinsky et al.,
2008), confirming the hypothesis of Proshutinsky et
al., (2002). Mechanically, the seasonal variability of
FWC follows wind curl changes with a maximum in
November-January and a minimum in June-August
depending on changes in atmospheric circulation. The
atmospheric and oceanic thermal regimes regulate
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