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Feb 2008 - A new report from the United
Nations Environment Programme (UNEP) describes
the dangers that global warming pose to
relatively pristine arctic waters. The findings
come in a new rapid response report, “In
Dead Water,” which maps the multiple impacts
of pollution, invasive species, over-exploitation
and climate change on the world’s seas and
oceans. Several of the threats described
in the report are particularly relevant
to the Arctic:
Climate change effects
on ocean circulation could negatively impact
arctic fish
The Arctic is one of
the world’s most productive fishing grounds,
supplying millions of tons of white fish
each year. The health of arctic fisheries
depends in part on natural ocean pumps that
circulate water, bringing nutrients to fisheries
and keeping them healthy by flushing out
wastes and pollution. According to the UNEP
report, global warming could disrupt this
natural pumping system, leading to serious
impacts on at least three-quarters of the
world’s key fishing grounds including in
the Arctic.
Cold-water arctic corals
at risk from ocean acidification induced
by global warming
“In Dead Water” explains
that as CO2 concentrations in the atmosphere
increase, so does ocean assimilation, resulting
in sea water becoming more acidic. This
will likely lead to a reduction in the area
covered and possible loss of arctic coral
reefs. Besides cold-water corals, ocean
acidification will reduce the biocalcification
of other shell-forming organisms which may
in turn impact the marine food chain up
to higher trophic levels.
Primary fishing grounds
are likely to become increasingly infested
by invasive species
As melting sea ice opens
summer shipping lanes across the Arctic,
a surge in shipping traffic could lead to
more invasive species introduced through
ship ballast water. The report finds that
the most devastating outbreaks of marine
infestations have been brought in along
the major shipping routes and primarily
established in the most intensively fished
and polluted areas on the continental shelves.
“Growing climate change will most likely
accelerate these invasions further,” the
report said.
Immediate action required
to build resilience against climate change
and prevent wide-spread collapse of marine
ecosystems
Urgent efforts to control
global warming are needed, but this alone
will not be sufficient according to UNEP
which advocates for a “synergistic” approach
to ecosystem and integrated ocean management.
UNEP calls for stronger regulation of fisheries,
protecting the continental shelves from
bottom trawling and other extractive activities,
establishing marine protected areas in deeper
waters, and reducing coastal pollution.
“Accelerating climate change and in-action
risks an unprecedented, dramatic and wide-spread
collapse of marine ecosystems and fisheries
within the next decade,” the report concludes.
For more information and to download the
full report, go to www.unep.org
