300 Resources from the Ocean Roor
10.5.3 Oil Spills. Certain kinds of pollution and dumping events have high media
visibility. Among these are oil spills. Such reports greatly raise the awareness level of
the public, regarding the potential problems stemming from misuse of the ocean, and
from irresponsible behaviour. In most cases, however, even massive spills (Torrey
Canyon, 1967; Amoco Cadiz, 1978; Exxon Valdez, 1989) have had limited impact in
tenns of area and time period affected (although that is of little comfort to those
whose livelihood is at stake).
One possible exception with potentially long-lasting effects may be the deliberate
release of oil in the upper Persian Gulf, from wells in Kuwait, during the hostilities in
1991. More than half a million tons of crude oil entered Gulf waters from the Mina
AI-Ahmadi oil tenninal, polluting 770 km of Saudi coastline. Significant impacts
from direct oiling are reported for the intertidal habitats (mangroves, sandy and rocky
beaches, and mudflats). Long-tenn damage is expected especially for the upper tidal
zone.
10.5.4 Chronic Hydrocarbon Pollution. In constrast to catastrophic spills, the
steady leakage of hydrocarbons from shipping and other industrial activities (including oil change in automobiles) receives much less attention. In 1985 the annual
petroleum hydrocarbon input to the sea was estimated to reach about 3 million tons -
with 12.5 % of it from tanker accidents. Additional risks arise from the operation of
more than 600 offshore oil production platfonns globally.
10.5.5 Radioactive Pollution. The principal source of artificial radionuclides in the
marine environment used to be nuclear weapon-testing. This source produced a very
low-level contamination with no obvious ill effects. Scientists use this contamination
for tracing water masses (e. g., by noting the tritium content of deep waters), and for
dating purposes in skeletal parts (e. g., a l4 C spike in the 1960s, in coral and shell). A
relatively smaller source of such nuclides are fission products introduced from military and commercial reactors. Dumping of radioactive waste has been prohibited
among the signatories to the London Dumping Convention (1972) since 1983. However, it may be more widespread than realized, as has recently become obvious (e. g.,
weapons disposal by the fonner USSR in the Barents Sea). Disposal of radioactive
materials (albeit of low-level activity) is also known to have occurred several decades
ago off California and off the U. S. East coast. The impact, if any, is unkown.
The massive release of radioactive materials to the atmosphere at Chernobyl
(April 1986) provided a unique opportunity to study the pathways of a number of
dangerous radionuclides, within the marine environment. Results (from trapping and
coring in the Black Sea and elsewhere) suggest that many, perhaps most, of the
metals involved (e. g., 137Cs) are rapidly removed from surface waters and transported to the sea floor within biogenic debris. Similar results are known from studying the effluent from the Hanford reactor, in the Columbia river mouth.
Problems of an entirely different order are posed by high-level radioactive waste.
Given that large amounts of such waste exist on land now, and that these pose a
considerable hazard for present and future generations, the disposal of such materials
through burial in the sea floor is an option that has received some discussion and
10.5.3 Oil Spills. Certain kinds of pollution and dumping events have high media
visibility. Among these are oil spills. Such reports greatly raise the awareness level of
the public, regarding the potential problems stemming from misuse of the ocean, and
from irresponsible behaviour. In most cases, however, even massive spills (Torrey
Canyon, 1967; Amoco Cadiz, 1978; Exxon Valdez, 1989) have had limited impact in
tenns of area and time period affected (although that is of little comfort to those
whose livelihood is at stake).
One possible exception with potentially long-lasting effects may be the deliberate
release of oil in the upper Persian Gulf, from wells in Kuwait, during the hostilities in
1991. More than half a million tons of crude oil entered Gulf waters from the Mina
AI-Ahmadi oil tenninal, polluting 770 km of Saudi coastline. Significant impacts
from direct oiling are reported for the intertidal habitats (mangroves, sandy and rocky
beaches, and mudflats). Long-tenn damage is expected especially for the upper tidal
zone.
10.5.4 Chronic Hydrocarbon Pollution. In constrast to catastrophic spills, the
steady leakage of hydrocarbons from shipping and other industrial activities (including oil change in automobiles) receives much less attention. In 1985 the annual
petroleum hydrocarbon input to the sea was estimated to reach about 3 million tons -
with 12.5 % of it from tanker accidents. Additional risks arise from the operation of
more than 600 offshore oil production platfonns globally.
10.5.5 Radioactive Pollution. The principal source of artificial radionuclides in the
marine environment used to be nuclear weapon-testing. This source produced a very
low-level contamination with no obvious ill effects. Scientists use this contamination
for tracing water masses (e. g., by noting the tritium content of deep waters), and for
dating purposes in skeletal parts (e. g., a l4 C spike in the 1960s, in coral and shell). A
relatively smaller source of such nuclides are fission products introduced from military and commercial reactors. Dumping of radioactive waste has been prohibited
among the signatories to the London Dumping Convention (1972) since 1983. However, it may be more widespread than realized, as has recently become obvious (e. g.,
weapons disposal by the fonner USSR in the Barents Sea). Disposal of radioactive
materials (albeit of low-level activity) is also known to have occurred several decades
ago off California and off the U. S. East coast. The impact, if any, is unkown.
The massive release of radioactive materials to the atmosphere at Chernobyl
(April 1986) provided a unique opportunity to study the pathways of a number of
dangerous radionuclides, within the marine environment. Results (from trapping and
coring in the Black Sea and elsewhere) suggest that many, perhaps most, of the
metals involved (e. g., 137Cs) are rapidly removed from surface waters and transported to the sea floor within biogenic debris. Similar results are known from studying the effluent from the Hanford reactor, in the Columbia river mouth.
Problems of an entirely different order are posed by high-level radioactive waste.
Given that large amounts of such waste exist on land now, and that these pose a
considerable hazard for present and future generations, the disposal of such materials
through burial in the sea floor is an option that has received some discussion and