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TL: GREENPEACE REPORT ON THE WORLD’S OCEANS - SUMMARY
SO: GREENPEACE INTERNATIONAL, (GP)
DT: MAY, 1998
Greenpeace Report on the World’s Oceans
Summary
The world’s oceans and seas cover 71% of the surface of the earth. This huge biological system
comprises very diverse habitats and is, in some respects, richer in biodiversity than life on land more major taxonomic groupings (phyla) of animals can be found in the oceans than on land.
Oceans are very important for human existence, not only because they supply us with fish and other
coastal resources, but also because they function as a regulator of atmospheric composition, nutrient
cycling and biological control of natural systems.
Marine ecosystems are under continuously increasing pressure. The population of the world is
rapidly growing and expected to reach some 7 billion by the year 2010, which means it will have
doubled in little under 50 years. The majority of the population lives near the coast and the impacts
of human activities are particularly evident in coastal regions. Measures are needed to protect the
coastal and marine environment. Such measures should take into account that there are considerable
uncertainties. Many of the processes normally taking place in the ocean are still not understood and
it is, therefore, very difficult to predict the responses of ecosystems to human interference. The most
widely accepted way to take such scientific uncertainties into account is through the adoption of the
precautionary approach. Such an approach to environmental protection aims to take measures to
prevent environmental damage by human activities, rather than attempting to react to problems after
they have been detected. It recognises scientific and technical limitations and promotes regulatory
action even where there is not conclusive evidence that the human activities cause environmental
damage. A great number of international fora have adopted a precautionary approach to
environmental protection, but it has not been effectively applied. Implementation of the
precautionary approach needs to be a priority and actively supported, promoted and implemented by
governments, intergovernmental organizations and the private sector.
Inputs of polluting substances
Of all polluting substances in marine environment, 77% come from human land based activities,
while shipping and sea dumping are thought to contribute the remainder. Both naturally occurring
and artificial substances like phosphates, nitrates, metals, radionuclides, and organic chemicals are
being discharged. Some of these are systematically accumulating in the ecosphere. There is
convincing evidence that widespread disturbance of biological systems is taking place as a result.
Organic chemicals
Organic pollutants like chlorinated pesticides (e.g. DDT, lindane), polychlorinated biphenyls
(PCBs,) the chlorinated dioxins and the polycyclic aromatic hydrocarbons (PAHs) are toxic,
persistent in the environment and can accumulate in the tissues of living organisms, causing a wide
range of problems. Chemicals containing chlorine are produced deliberately as commercial
products, but are also produced as unwanted by-products in chemical processes which use chlorine.
Chlorinated chemicals have been a major focus of research and their impact upon the marine
environment may increase in the future. PAHs are produced in industrial combustion and
petrochemical manufacturing processes using fossil fuels as well as from natural sources such as
forest fires. Because of the persistence of these chemicals, they will continue to damage the
environment even after they are banned or their production is severely restricted. For this reason it
is all the more urgent that restrictions and bans be implemented as soon as possible.
Long-term research programmes have shown that persistent organic pollutants are globally
transported towards the cold polar regions resulting in high levels of contamination in areas remote
from sources of industrial pollution. The problem of global transport of persistent chemicals to
remote regions is likely to increase. Many developing countries are beginning to use industrial
processes which make use of toxic chemicals in part as the result of the export of outdated
technology by industrial countries. In addition, pesticides that are highly restricted in industrialised
countries are being increasingly used in agriculture and public health programmes in developing
countries to control pests and diseases. This explains, for example, the presence of high residue
levels of DDT in the atmosphere and waters of tropical Asia. Chlordane and PCB emissions also
appear to be increasing in tropical countries. Transport from these areas to remote polar areas
appears to be inevitable. Even when regulatory measures are taken, high levels of some of these
pollutants will persist for many decades in those remote areas. Pollution by organochlorines in
remote areas can, therefore, only be brought under control by a complete ban on their production
and use throughout the world. These chemicals, moreover, are only a small component of all the
chemicals discharged to the marine environment, many of which cannot be easily identified.
Radioactive pollution
Radioactive isotopes are another class of polluting substances for which the current scale of
environmental impact is uncertain and a matter of serious concern. Low level concentrations of
artificial radionuclides are measurable in the oceans world-wide as a result of discharges from
nuclear facilities and weapons testing. Radiation can damage organisms at a cellular level and cause
cancer or genetic mutations. Although the largest source of artificial radionuclides in the oceans
resulted from the fallout from weapons testing, other sources are the nuclear industry and the
military, whose dumping, accidental losses and discharges provide highly localised inputs. In
particular, plants where spent nuclear fuel elements are reprocessed have become major contributors
of radioactive discharges. Two major commercial reprocessing operations are located in Europe (La
Hague, France and Sellafield, UK) but others are known to exist in Japan, India and Russia. The
discharges of the European reprocessing plants have risen significantly in the past decade and have
resulted in elevated radiocaesium levels over the whole of the North Atlantic. The increased nuclear
reprocessing discharges have serious implications for marine and terrestrial food chains since
marine and estuarine organisms are able to accumulate radionuclides. In 1996, concentrations of
17,000 Bq/kg technetium-99 were measured in lobster found off the coast of the reprocessing plant
in Sellafield. This was twice as much as the concentration measured in 1995 and 44 times as much
as in 1993. Many of these discharged artificial radionuclides have extremely long half lives and are
unknown in nature. Continuing discharges cause a build-up of these elements in the ecosphere. In
keeping with the precautionary principle, the discharge and emission of nuclear reprocessing wastes
must be stopped.
In addition to the artificial sources of radionuclides, naturally occurring nuclides are mobilised in
large quantities by oil production and phosphate rock processing for fertiliser and detergent
manufacture. This rock processing can lead to marine animals, particularly fish, accumulating high
levels of the isotope polonium-210, and these can be an important source of polonium-210 to
humans.
Knowledge of the physical behaviour of nuclides in the environment is very incomplete. Even less
is known about the effects upon wildlife of continual long-term, chronic exposure. Environmental
protection from radiation is based on the assumption that if humans are adequately protected, then
other living organisms are likely to be so too. But this crucial assumption has little scientific basis.
In any case, it is clear that levels of radioactivity in some organisms in the natural environment may
exceed human dose rates by a large margin. For instance, a maximum dose of 1mSv per year is
recommended for humans but grey seals near Sellafield were estimated to be exposed to a dose of
36 mSv per year from the isotope caesium-137 alone.
Given the lack of knowledge and uncertainties about the environmental impact of the long lived,
persistent radionuclides and organic chemicals, a precautionary approach to the regulation of these
hazardous substances is to eliminate discharges and emissions.
Marine fisheries
Marine fishing is an important human activity. It generates around 1% of the visible global
economy, and together with related industries it supports the livelihoods of around 200 million
people globally. Fish stocks around the world are being too intensively exploited. According to the
most recent FAO figures, most major fisheries are fully to over exploited. The decline of many fish
stocks is due to poor management and regulation. The problem is that too many boats are chasing
too few fish. Estimates suggest that the global fishing fleet has 30-50% more capacity than needed
to sustainably harvest the worlds stocks and the key to this overcapacity problem is found in the
heavy subsidies provided by governments. As a result of overcapacity in world fishing fleets, the
costs of fishing have been estimated to exceed the gains by some $US 16 billion annually. For every
single dollar earned in 1989, for example, the costs associated with catching the fish were $US1.77.
While the continuing subsidies to the industry may help to soothe economic impacts of fisheries
decline, it does so by encouraging continued over-exploitation of resources.
Fisheries management is generally based on biological advice on stock estimates and predictions.
This advice is used to set a quota that should control fishing mortality. The inadequacies of current
management systems are exposed by fisheries that have collapsed together with documented
examples of continued overexploitation of fish stocks. Collapse and overexploitation occur even
where a good body of data exists to inform managers. The cod and herring stocks in Canada and the
North Sea are such examples. This leaves little hope for the stocks that are overexploited in the
absence of good data. The Southern Bluefin Tuna for example is a highly migratory stock whose
biology is incompletely understood. It is fished by a number of nations, and fishing is poorly
regulated on an international level. As a result the stock is in a critical state. If current catch rates
continue and Japan increases its catch, in defiance of international agreements, then there is around
a 60% probability that the number of spawning adults of the stock will be reduced to zero by the
year 2020. This would result in commercial extinction of the species, if not actual extinction.
Fisheries do not only affect the targeted fish stocks, but impact the whole ecosystem. The most
compelling evidence of general global scale ecosystem disturbance has been provided by reanalysis
of FAO fisheries data. This has revealed the trend of progressively fishing down food chains. After
depletion of the original target stock, the fisheries sector responds by targeting species that feed
lower in the food chain. Hence, there is a trend in global fisheries of shifting from predatory
demersal fish to pelagic fish lower in the food chain. This strategy brings with it a real possibility
of wholesale changes marine ecosystems by altering the way in which energy flows through them.
Depending on the local situation, the end result could be a complete shift away from commercially
exploitable fish populations. One hypothesis, for example, is that the Southern North Sea could
become dominated by jellyfish as top predators rather than commercially exploitable species.
Bycatch of non-target species and discarding of unwanted catch also contribute to altering species
balance and ecosystem dynamics. Bycatch is a feature of many fisheries and is a problem of global
dimensions. Discarded bycatch in the global fishing industry are estimated at some 27 million
tonnes, of which 37.2% are associated with various shrimp fisheries. Bycatch not only affects
commercial and non-commercial fish species, but also bottom dwelling animals, whales, sea turtles
and birds. Longlining for example is accompanied by large bycatches of seabirds. Some albatross
populations such as the wandering albatross on Macquarie Island have been driven almost to
extinction.
Fishing gear also causes physical disturbance. In heavily fished areas, the bottom may be trawled
several times a year. Dredges and bottom trawls are highly damaging to marine habitats. They
scrape or plough the seabed, disrupting sediment, destroying habitat and killing large numbers of
bottom-dwelling organisms. Severe habitat destruction can also occurs in coral reef fisheries. The
use of cyanide poison to stun fish can kill most reef organisms, leaving much of a reef dead and
degraded. Dynamite fishing also causes physical destruction of the reef environment.
Aquaculture
Aquaculture is a booming business, due to the rapid growth in demand for high value marine
products like salmon and shrimp. The recent expansion in production of these species is reflected in
an explosive increase in the number of intensive culture operations in coastal areas. Improvements
in yield per unit area have been achieved by using high value feedstock and by using antibiotics and
pesticides to control diseases and parasites. While traditional extensive methods of shrimp
production yield between 100 and 500 kg shrimp per hectare, intensive pond culture can increase
this to 1000-10,000 kg per hectare.
There are many environmental problems associated with intensive aquaculture of marine species in
the coastal zone. A clear example is the large-scale destruction of mangroves in Asia and Latin
America for the construction of intensive aquaculture facilities. In the Philippines, aquaculture has
contributed significantly to the removal of 75% of the original mangrove habitat. In Ecuador, the
rapid growth of shrimp production had claimed 12,000 ha of virgin mangrove by 1987. Intensive
shrimp ponds developed from mangroves are usually abandoned as soon as yields begin to fall. This
occurs as a result of declining water quality. Poor husbandry and inadequate waste management
cause outbreaks of disease. Subsequently, new areas are cleared and developed. The mean lifetime
of such ponds in Thailand is estimated at only 7 years. This method of shrimp production is
ultimately unsustainable. This became clear when aquaculture production crashed in Taiwan in the
late 1980’s due to high costs, pollution and disease. Such unsustainable ‘shifting aquaculture’
operations supply a large proportion of global shrimp production at the expense of destroying
irreplaceable coastal ecosystem.
Intensive aquaculture emits large quantities of nutrients and organic matter into the environment.
For every tonne of cage-farmed salmon produced, an estimated 2.5 tonnes of organic waste may be
generated. In intensive shrimp ponds ammoniacal nitrogen is accumulated, which can be highly
toxic to many marine species. Although both cage and pond aquaculture undoubtedly lead to local
increases in nutrient loading, there is hardly any information on direct impacts. The aquaculture
industry uses a variety of antibiotics, pesticides and detergents. Information on the types and
quantities of chemicals employed in many countries is very scarce. Many of the chemicals used to
control disease are toxic to a range of species, persistent in the environment and able to accumulate
in biological tissues. They may create problems with residues in the cultured fish and shrimp, affect
the surrounding environment, and allow antibiotic-resistant bacteria to enter the environment. Some
of these bacteria may be pathogenic to marine species or even humans. In addition, the escape of
farmed fish from cages may alter the genetic composition of wild stocks if they interbreed, resulting
in reduced fitness of wild species. Despite development of regulations and technological
improvements, the environmental and health problems of aquaculture remain significant and seem
set to increase, given the continued economic pressure for growth of the aquaculture industry.
Impacts of shipping
Seaborne trade increased by around 45% between 1986 and 1995, and currently shipping is
responsible for the carriage of some 80% of the volume of goods traded globally. Ships can cause a
variety of problems in marine ecosystems. Many of the goods transported are hazardous. Losses of
hazardous packaged goods such as pesticides occur regularly although such incidents are not
systematically recorded. Chemical tank washings, discharge of oily wastes and oil-contaminated
ballast and wash waters are significant sources of marine pollution. Shipping is responsible for an
estimated 568,000 tonnes of oil entering the marine environment annually. Marine engines are also
among the most highly polluting combustion sources, due to the use of low grade residual oils as
fuel. Ships are, therefore, significant contributors to atmospheric pollution. Another important
pollutant associated with shipping is the chemical applied to the hull of the ship to prevent the
growth of fouling organisms. The most commonly used antifouling preparations contain tributyl-tin
(TBT), a very toxic chemical. This acts as an endocrine disrupting chemical in marine snail species.
Even extremely low concentrations can cause population declines by affecting their reproduction.
TBT has also been found in the blubber of several marine mammal species. Finally, ballast water of
ships can contain species of plants and animals that are removed from their native ecosystem and
introduced in another. The impacts of such alien species are not well documented in most areas but,
where information is available, for example the invasion of American comb jellyfish in the Black
Sea, the impact can be severe.
Offshore activities
The offshore oil industry discharges large quantities of oil-based drilling muds with drill cuttings.
These muds are toxic and have been found to affect reproductive development in bivalves and
immune response in fish. Effects on overall benthic community structure have been detected on a
distance as far as 2-6 km from disused platforms in the North Sea. Production waters are also
discharged into the sea. These contain not only oil but also chemicals that either originate when the
oil or gas forms, or are added during the treatment of the hydrocarbons at the production platform.
The use of chemicals is poorly controlled and documented, but it is clear that they can contribute to
contamination of drill cuttings and produced waters. Some of the chemicals used, such as
nonylphenol, can disrupt the hormone system and the reproduction of fish. In comparison to
land-based industry in Europe, the offshore industry is relatively poorly regulated. There is a
requirement for greater transparency and control of offshore operations.
At minimum the offshore industry should be bound to apply the restrictions which exist for the
dumping and discharge of wastes from other industries. This includes the need to ban the dumping
at sea of the hundreds of offshore oil and gas installations that are due to be decommissioned in the
next decades, given that not enough attention has been given to the “cumulative impact” of the
dumping at sea of many large installations, nor to the environmental benefits arising from steel
recycling (particularly through CO2 emission savings).
Climate change
Since pre-industrial times, concentrations of carbon dioxide, methane, nitrous oxide and industrially
produced gases, including the CFCs, fluoroform and sulphur hexafluoride have risen steadily in the
atmosphere. These gases all have in common that they act as "greenhouse" gases. These trap solar
radiation reflected from the surface of the Earth. Carbon dioxide emitted from the burning
immense quantities of fossil fuels is the largest contributor to the effect. Based on computer models
and temperature measurements in the atmosphere, it is estimated that the increase of the global
average surface air temperature between 1990 and 2100 will be between 1 and 3.5 ºC. Such an
increase is extremely large and will be associated with major climatic changes around the world.
Model predictions are highly uncertain, due to natural variability and poor understanding of global
processes and feedback mechanisms. Nonetheless the Intergovernmental Panel on Climate Change
in 1996 considered that "climate has changed over the past century" and that "the balance of
evidence suggests a discernible human influence on global climate".
Potential impacts of climate change upon the oceans have been less studied than the impacts upon
terrestrial systems. This does not mean that such impacts are likely to be negligible. The oceans play
a central role in shaping the earth’s climate and its natural variability. Oceans absorb carbon dioxide
and other atmospheric gases, and their circulation redistributes heat and water. The most obvious
potential impact of climatic change is on sea level. Over the past 100 years, global sea level has
risen by between 10 and 25cm. For each centimeter of sea-level rise, beaches may erode a meter
landward; for every 10-cm rise, saltwater wedges in estuaries and tidal rivers may advance a
kilometer; and any sea-level rise will increase salinity in freshwater aquifers. Rising of sea levels
will result in land-loss and coastal habitat loss in many countries. Bangladesh may lose 17.5% of its
land area, and this could be as much as 80% for Majuro Atoll in the Marshall Islands. Increases in
water temperature are likely to have severe impacts upon coral reefs by contributing to bleaching of
corals.
A consistent prediction of the mathematical models used to study climate change is that changes are
likely to be greatest in the polar regions. These regions play a fundamental role in ocean circulation
patterns. In turn, these determine climate patterns over the rest of the globe. Climate change in the
polar regions may, therefore, not only directly change these biologically rich marine ecosystems, but
also induce other changes worldwide. For example, according to models and observed trends, the
Arctic is warming faster than the rest of the world. Precipitation in the region is likely to increase
by 3-6% per degree of warming. A recent analysis suggests that the areal extent of sea ice in the
Arctic has decreased by 2.9% ±0.4% per decade since 1978. Arctic glaciers are also retreating. The
ice thickness of Alaskan glaciers has decreased by around 10m over the last forty years. Increased
precipitation and melting of ice could make the upper layers of the Arctic less saline. This, in turn,
could change the thermohaline circulation which drives the global ocean circulation and the regional
current systems. These changes are also mirrored in the collapse of Antarctic ice-shelves in recent
years.
In addition to the warming of polar regions, important human impacts upon the natural stratospheric
ozone have been detected. Every spring for over 20 years a hole has appeared in the ozone layer
over Antarctica and has increased in size over the years. Substantial depletion of the ozone layer
over the Arctic is now also being recorded. The production and use of various chlorinated and
brominated chemicals are responsible for this ozone depletion. This depletion has resulted in
increased levels of UV radiation at the earth’s surface. UV-B radiation is detrimental to various
marine species in the upper layer of the ocean and reduces primary production, which is the basis of
marine food webs. This may have a considerable impact on marine ecosystems on a global basis.
CONCLUSION
The Greenpeace Report on the World’s Oceans is a comprehensive, but by no means exhaustive,
review of the many threats facing the world’s oceans and seas today.
1998 has been designated by the United Nations as the International Year of the Ocean.
Greenpeace has been actively campaigning on a variety of oceans related issues for the past 27 years
and has put forward a set of ten demands to governments and the UN system. Greenpeace is
calling on governments to meet these demands to effectively address the problems outlined in the
Greenpeace Report and to make the UN Year of the Ocean a meaningful event. The failure of
governments to seize the opportunity and act decisively will result in continued degradation of the
world’s oceans at the expense of present and future generations of humankind and the health and
abundance of all life dependent on the seas.