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Policy
Implications of Global Warming for
Coral Reefs and Fisheries of Small Island States
December 31 DRAFT
[Briefing Paper for UN Summit of Small Island Developing States]
Thomas J. Goreau, Ph.D., President, Global Coral Reef Alliance,
Cambridge, MA, USA
Raymond L. Hayes, Ph.D., Professor, Howard University College of
Medicine, Washington, DC, USA
Leonard Nurse, Ph.D., Permanent Secretary, Ministry of Environment and
Natural Resources, Barbados, BWI
Global warming poses the most immediate threat to both living and non-living
coastal resources of small island nations. Yet the focus of policy makers has
largely been on sea level rise that will take many times longer to become
serious in most places. Melting of glaciers and ice caps will require centuries
to thousands of years, and will take several decades to severely impact most
tropical islands. However global warming has already devastated the coral reefs,
fisheries, tourism, and shore protection of almost all small island states, and
is likely to deliver even more crippling blows in the next few years.
Denial and misinterpretation of data about global warming have obscured
understanding of the real impacts of climate change. Small island nations are
especially vulnerable due to reliance on outside advice. By ignoring the already
observed consequences of rising temperature, focus is being misplaced upon the
much slower and more uncertain impacts of sea level rise, and the impacts of
increasing acidity of the oceans caused by increasing carbon dioxide
concentrations. These could only be felt centuries to millennia after
reef-building corals have already been killed by excess heat. Such misdirected
focus serves only to distract attention from the immediate risks of high
temperature exposure.
While it has become increasingly impossible with each passing year to deny that
high temperature is now the major coral killer worldwide, the finger has been
adroitly pointed at El Niņos. References to "El Niņo-caused coral bleaching" are
misleading because they blame a natural phenomenon instead of attributing coral
bleaching to global warming caused by human activities. Claiming that "this is
all part of a natural cycle and variation" erroneously suggests that coral death
is a rare and extreme event that will go away all by itself as things return to
"normal".
Attempts to characterize global warming as El Niņo-derived is an irresponsible
red herring for several reasons. El Niņo is, in fact, an atmospheric pressure
wave encompassing a pattern of multi-year oscillations of alternating high and
low pressure across the width of the Pacific. El Niņos have been occurring for
millions of years, but coral mortality on a large scale was not observed before
about 20 years ago. Global warming is superimposed upon both El Niņo and
intervening periods, making both hotter. During an El Niņo the eastern Pacific
gets hotter than normal, while the western Pacific gets colder, and the effects
in the Indian Ocean and Atlantic are minor. Yet in 1998, the hottest year in
history and an El Niņo year, these areas had record high sea surface
temperatures. Many corals bleached and died in all oceans, including most in
the Indian Ocean. 2002 was the second hottest year in history. However, it was
not an El Niņo year, and corals suffered devastating mortality from high
temperature all across the southern Pacific from Australia to Panama. This is
clearly a global warming pattern in space and time, not an El Niņo pattern. All
years since 1998 have been only a few tenths of a degree below the record. It
will now be only a matter of time until years as hot as 1998 and 2002 will
re-appear.
We have recently tabulated satellite measurements of sea surface temperature at
over 200 sites throughout every coral reef region worldwide (Goreau & Hayes, in
press). The data show that coral reef areas are warming faster than the global
average, so bleaching is likely to recur soon in every reef tract. This
contrasts with claims that these effects are decades to centuries or millennia
away, as is proposed by climate change models. These models do not adequately
account for current temperatures or trends in reefs and probably will not be
able to accurately predict future reef conditions either.
Our data of global changes in ocean surface temperatures between 1982 and 2003
during the warmest months of non-El Niņo years show that there are strong
regional trends in the rate of warming that are affecting ocean circulation
patterns globally. Warm currents are increasing their heat transport; cold
currents are concurrently reducing theirs. Increasing temperature differences
are accompanied by increased wind speed in some areas. This association is seen
especially in the centers of the large ocean basins and around Antarctica, where
increased flow of cold water to the surface is driven by high winds. In
contrast, major coastal areas of high productivity are showing higher than
average warming since the flow of nutrient-rich deep waters is reduced, causing
food chains to collapse even in the absence of over-fishing. As a result of
these patterns, most coral reef regions are warming faster than normal and are
imminently threatened with local extinction from climate change, with negative
impacts on fisheries, tourism, and coastal protection. A few areas are protected
by increased cold water flow, but in these regions the coral reefs are overgrown
by algae, sponges, and soft organisms that are greatly inferior fish habitats
and offer no protection against erosion of coastlines. In addition the world's
major fisheries face collapse due to increasing temperature. Areas that might
provide compensatory habitats are remote, far less productive, and unable to
balance these losses.
The policy implications of this new and expanded sea surface temperature
database are broad and profound. Small island developing states, and indeed over
100 coral reef countries, are likely to be the earliest and also the worst
victims of global warming as they suffer losses to the coastal resources that
provide their food, tourism earnings, beaches, and shore protection from storms.
The Kyoto agreement would not have met the needs of small island states, even if
it had been implemented. The Kyoto Protocol was an agreement to stabilize the
rate of global warming, not to stop it or to stabilize temperature at
ecologically safe levels. Therefore, Kyoto conferred a death sentence upon their
coral reefs. Damage to coral reefs is already so severe that marine protected
area conservation strategies now proposed by aid agencies, governments, and many
major environmental organizations will certainly be ineffectual.
The world is changing so fast that old strategies can not possibly work to solve
current and future problems. Focus needs to be shifted to large-scale
restoration of coral reefs and fisheries that are already degraded. Island
nations have not been persistent enough in defending their own interests and
ensuring that international climate change agreements protect them from the
impacts of climate change. They have been misled to focus on long-term rather
than immediate threats and have lost focus on reversing the current decline of
their resources. New approaches must be adopted to increase the quality of
marine habitats and to sustain residual marine resources before they are lost
completely and forever.
Goreau, TJ and RL Hayes 2004. Regional patterns of sea surface temperature rise
and the future of coral reefs. World Resources Review (in press).
Dr. Thomas J. Goreau
President
Global Coral Reef Alliance
37 Pleasant Street, Cambridge, Massachusetts 02139, USA
telephone: 617-864-4226, 617-864-0433
E-mail: goreau@bestweb.net
Web site: http://www.globalcoral.org
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