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CONTENTS
IN FOCUS
p 2 - A carbon sink that can no longer cope?
NEWS
p 6 - Multimillion dollar water project for Iraq
p 7 - A strategic plan for Afghanistan’s universities
p 8 - Two years to assess global agriculture
p 8 - Asian journalists learn to report the science
of HIV/AIDS
p 9 - UNESCO and WMO join forces to combat flood damage
p 10 - The ICTP turns 40
INTERVIEW
p 10 - Osman Benchikh on why the age of renewables has
now begun
HORIZONS
p 13 - The solar school
p 16 - Who needs maths at a time like this?
IN BRIEF
p 20 - Diary
p 20 - New releases
p 20 - Governing bodies
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Acid
rain, acid ocean
Homo industrialis has only walked the Earth for 200 years
but, in that time, he has burnt ever-greater amounts of coal
and oil, and churned out vast quantities of concrete. Half
the carbon produced by this frenetic industrial activity has
seeped into the world’s oceans.
The
oceans have become a sink – and a very effective one at that.
A study published in Science last July estimates that the
oceans have absorbed 118 billion metric tons of carbon dioxide
(CO2) over the past two centuries, about one-third of their
long-term potential. As a result, the concentration of CO2
in the atmosphere has only increased by 36% over the same
period. Without the ocean carbon sink, the atmospheric concentration
of CO2 would have been higher today and global warming more
severe. We owe the oceans a lot.
But, we ask in the current issue, can the ocean continue to
cope with being a vast carbon sink? A symposium organized
by UNESCO’s Intergovernmental Oceanographic Commission last
May has concluded that we may yet pay a very high price for
this service to humanity. The high concentration of CO2 in
the oceans is making them more acidic and there are signs
that this is beginning to affect marine life.
With fossil fuel-burning on the increase rather than the reverse,
things are poised to get worse for corals, pteropod molluscs,
some plankton and perhaps even some fish, which may encounter
a whole range of ‘health problems’ as the ocean acidifies,
including reproductive difficulties and asphyxiation. That
would spell catastrophe for the world’s fishing and coastal
tourism industries.
As
the surface waters become more saturated with carbon, the
ocean may also become a less efficient sink. With less carbon
being absorbed by the oceans, more would enter the atmosphere.
That would accelerate global warming.
Most
experiments have been conducted in laboratories up until now,
so we cannot say for certain at this stage what lies ahead
for the marine food chain. But we need to find out. And fast.
Hence the resolve of the science meeting last May to fix urgent
priorities for studying ex situ, and above all long-term in
situ, the effects on marine life of an acidifying habitat.
W.
Erdelen
Assistant Director-General for Natural Sciences
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UNESCO
Scientific 
