Å®ÉúСÊÓƵ

Oceans were seen at the summit as a new target for environmental protection
– an issue potentially as important for the 1990s as rainforests were in
the 1980s.

Agenda 21 gives science a critical role in reducing ‘the high degree
of uncertainty in present information, which inhibits effective management’
of the oceans. It commits nations to ‘long-term cooperative research’ to
collect data.

Speaking at a summit meeting, Gunnar Kullenberg, general-secretary of
UNESCO’s Intergovernmental Oceanographic Commission, called for up to $2
billion a year to fund a Global Ocean Observation System, a central proposal
in Agenda 21’s chapter on the oceans.

Leader of the US delegation to the summit, William Reilly, called the
oceans ‘a US priority’ and gave strong backing for a high-level international
meeting to discuss worsening pollution of coastal zones.

According to Kullenberg, ‘sooner or later, most pollution ends up in
the oceans. We know we are overstretching the marine biological system,
but we are unable to quantify the impact to make predictions for policy-makers’.

Both he and Agenda 21 highlight the importance of quantifying the role
of oceans in climate change. The oceans, said Kullenbury, are a ‘sink’ for
half of the carbon dioxide put into the atmosphere. ‘The Climate Convention
says we must protect carbon sinks. But in the case of oceans we must find
out how.’

Global warming and pollution, he said, could reduce the ability of oceans
to soak up carbon from the air. Warmer oceans will be increasingly stratified,
and this would reduce carbon dioxide uptake by restricting the mixing processes
that take dissolved carbon down to the depths of the oceans.

Both pollution and increasing ultraviolet light streaming through ozone
holes could reduce production of plankton. Like forests on land, plankton
absorb carbon. Finally, changes in the formation of sea ice could alter
the related formation of ‘deep waters’, dense saline water that descends
to the ocean bottom in Arctic regions. ‘The North Atlantic zone of deep
water formation,’ said Kullenberg, ‘is a very considerable carbon sink.’