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Ocean Studies
Introduction to Oceanography
American Meteorological Society
Chapter 15
Ocean Problems and Policy
© AMS
Case in Point
– In the U.S., removal of even small dams on
rivers and streams is a relatively new strategy
intended to benefit downstream ecosystems
including marine ecosystems.
– Breaching of the Edwards Dam on the
Kennebec River in Augusta, ME occurred on
1 July 1999.
• Decimated local fish populations, first by flooding
critical habitats and then by preventing
anadromous fish from migrating from the ocean to
their upstream spawning grounds
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Case in Point
– Removing the Edwards Dam reopened about
30 km (19 mi) of fish spawning and nursery
habitat in the Kennebec River.
– Populations of 10 species of anadromous fish
exhibited varying levels of recovery.
– Many bird populations also increased in
number and water quality improved.
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Ocean Problems and Policy
• Driving Question:
– How does national and international ocean
policy promote wise stewardship of the world
ocean?
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Ocean Problems and Policy
• In this chapter, we examine:
– The impact of human activities on the ocean
and coastal zone, marine ecosystems and
habitats, and how society is attempting to
minimize that impact, remediate past damage,
and head off future problems
– Human interaction with the ocean and coastal
zone with emphasis on remediation,
sustainability, and stewardship
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Milestones in Ocean Governance
• FREEDOM OF THE SEAS
– Partitioning of the coastal ocean began in the late
1700s, when the new United States of America
claimed a 5-km (3-mi) “territorial sea” off its coast.
– The Magnuson-Stevens Fisheries and Conservation
Act (1976) extended the jurisdiction of the nation’s
fisheries-management seaward from the shore to 330
km (200 mi), waters that were formerly heavily fished
by foreign vessels.
• Sustainable Fisheries Act amended the Magnuson Act in
1996 imposing strict new mandates to halt overfishing,
rebuild overfished stocks, reduce bycatch, and protect
essential fish habitat
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Milestones in Ocean Governance
• FREEDOM OF THE SEAS
– The first commission to develop a national ocean
policy for the U.S. was the Commission on Marine
Science, Engineering and Resources, more
commonly known as the Stratton Commission.
– Recognizing that the ocean plays an integral role in
the economic, environmental, and security interests of
the U.S., a second U.S. Commission on Ocean Policy
was established to make recommendations to the
President and Congress for a coordinated and
comprehensive national ocean policy.
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Milestones in Ocean Governance
• FREEDOM OF THE SEAS
– In 1982, the United Nations Convention on the Law of
the Sea expanded the narrow territorial waters 20 km
(12 nautical mi) from the shoreline and authorized
nations to establish Exclusive Economic Zones
(EEZs).
• In 1996, EEZs were extended to the edge of the continental
shelf when the shelf edge was more than 370 km (200
nautical mi) offshore.
• Within their individual EEZ, each coastal nation has the same
rights and responsibilities that they exercise over their land
areas.
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Milestones in Ocean Governance
• FREEDOM OF THE SEAS
– At the beginning of the 21st century, about two-thirds
of the ocean was part of the ocean commons and
beyond the control of any coastal nation.
• Little or no regulations
– As the global human population continues to grow
and increasing demands for natural resources exceed
supplies on land, ocean resources are likely to be
increasingly exploited.
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Milestones in Ocean Governance
• ANTARCTIC TREATY
– The Antarctic Treaty System is a complex of
arrangements that regulate relations among nations
near Antarctica and those conducting research and
exploration there.
– Ensures that no national claim of territorial rights in
Antarctica or the surrounding waters will ever be
legally recognized and that Antarctica forever would
be used exclusively for peaceful purposes
• Applies to waters, ice shelves, and islands in the Southern
Ocean (south of 60°S)
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Human Impact in the Coastal Zone
• HUMAN POPULATION TRENDS
– About 80% of the land on Earth is now inhabited by
people or otherwise impacted by human activities
such as agriculture, pasturing animals, growing trees,
mining, or urban development.
– Half the world’s people live within about 30 km (19 mi)
of the coastline and nearly 75% within 50 km (31 mi).
– Population growth in the coastal zone during the first
half of the 21st century is expected to take place in
small- and mid-sized communities in developing
countries.
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Human Impact in the Coastal Zone
• ENVIRONMENTAL POLLUTION
– Pollution is defined as an intentional or unintentional
disturbance of the environment that adversely affects
the wellbeing of organisms directly or the natural
processes upon which they depend.
– All organisms disturb their environment by exploiting
and utilizing resources, as well as producing waste
products.
• Humans have been particularly pervasive in their disturbance
of the environment so that many areas of the world suffer
from air and water pollution.
• Natural physical forces such as hurricanes, floods, tsunamis,
volcanic eruptions, and earthquakes disturb the Earth
system.
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Human Impact in the Coastal Zone
• ENVIRONMENTAL POLLUTION
– We can do something about disturbances for which humans are
responsible.
• Not everyone agrees that action is needed or on what specific steps
should be taken when there is general agreement that a problem
must be dealt with.
– The human carrying capacity of a region is based on the
maximum rate of resource consumption and waste discharge
that is sustainable indefinitely without progressively impairing
ecosystem productivity and integrity.
– Assimilative capacity is the amount of waste that an ecosystem
can assimilate without damaging ecosystem functions or building
up waste products to levels that may cause unwanted or harmful
impacts on living organisms.
– The most deficient resource is known as the limiting factor.
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Human Impact in the Coastal Zone
• COASTAL ZONE
MANAGEMENT
– The federal government assists
coastal states in managing and
protecting their coastal
resources through the Coastal
Zone Management Program
(CZMP) authorized by the 1972
Coastal Zone Management Act.
• Promotes comprehensive
management of coastal
resources
• Seeks to protect those
resources for future
generations while balancing
competing economic,
cultural, and environmental
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issues
Oil Spills
– Releases of oil, hazardous substances, and
other pollutants continue to threaten fragile
coastal ecosystems.
– Oil is spilled accidentally or intentionally into
the ocean on a daily basis.
• Oil routinely enters the ocean from storm sewer
and wastewater discharges.
• A large but mostly unknown quantity of oil enters
the ocean naturally, leaking through the seafloor
into the overlying water.
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Oil Spills
– One of the world’s most well-known oil spills occurred
in the coastal waters of Alaska in 1989.
• Nearly 42 million liters (11 million gal) of crude oil spilled into the
ocean, creating the largest oil spill in U.S. history.
• Devastated many communities of marine organisms, which were
covered by oil and thereby exposed to many toxic constituents.
• Also decimated sea birds; an estimated half-million birds
representing 90 species probably died.
• Marine mammal populations near the oil spill were also affected.
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Oil Spills
– Much of the oil entering the coastal ocean
comes from untreated storm-sewer
discharges.
• Developed ways to use natural processes to treat
these waters at low costs
• Recent technological advances have made
possible a more rapid and effective response to oil
spills in the ocean.
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Dams and Marine Habitats
– A dam is a barrier constructed across a
watercourse that impounds water in an
upstream reservoir.
– Worldwide about 15% of Earth’s renewable
freshwater supply is stored in reservoirs
behind dams.
– Most dams and associated reservoirs are
multipurpose structures.
• Impound water for irrigation, recreation, and
municipalities
• Used for flood control, to generate hydroelectric
power, and to regulate water levels for navigation
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Dams and Marine Habitats
– The Hoover Dam,
constructed on the
Colorado River in the
1930s, marked the
beginning of the era of
so-called superdams,
dams that are more
than 150 m (490 ft)
high and capable of
storing one or more
years of the average
annual flow of a river.
© AMS
Navigational dam located
just upstream of Zanesville,
OH on the Muskingum
River.
Dams and Marine Habitats
– Dams cause major dislocations among native and
indigenous peoples who are forced to move from
areas flooded by reservoirs, losing their homes,
farms, and communities.
– Dams have caused major alterations in coastal river
and marine ecosystems.
• The effect of dams on anadromous fish populations has been
especially severe.
• Salmon populations plummeted from an estimated 16 million
before the rivers were dammed to 300,000 by early in the
21st century.
• Some salmon stocks are now nearly extinct.
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Dams and Marine Habitats
A new Alaskan Steep Pass fish ladder just prior to
installation at a small dam in Byfield, Essex County,
MA. The old fish ladder failed to provide anadromous
fish with regular access to their spawn in grounds in
the Parker River.
© AMS
Dams and Marine Habitats
– The most radical proposal to protect and restore wild
salmon stocks calls for removal or partial breaching of
some of the large hydroelectric dams.
• Either removal or breaching of dams would reduce the
amount of hydropower generated.
– Dam removals can also cause problems.
• Arise from the downstream release of sediments formerly
trapped in the reservoir behind the dam.
• Influx of sediments alters downstream habitats wiping out
organisms such as insects, algae, and filter feeders.
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Restoring Chesapeake Bay
– Since 1983, the Chesapeake Bay estuary has been the focus of
the nation’s largest federal-state environmental restoration
project, the Chesapeake Bay Program.
– Following settlement by European colonists at the beginning of
the 17th century, human activities greatly modified Chesapeake
Bay with important consequence for the functioning of the
ecosystem.
• Much of the original forest that covered its watershed was
cleared and converted to agricultural lands, roads, cities, and
suburban developments.
• People converted the Chesapeake Bay watershed from a
closed system to an open system.
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A
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C
B
In the summer of 2004, NOAA
provided funds to help the town
of Henniker, N.H., remove the 18foot-high West Henniker Dam,
which blocked migratory fish and eel
passage to upstream spawning
and feeding grounds. Photos
show the dam before removal (A);
during removal (B) and the
Contoocook River after removal of the
dam (C).
Restoring Chesapeake Bay
Since 1983, the
Chesapeake Bay
estuary has been the
focus of the nation’s
largest federal-state
environmental
restoration project,
the Chesapeake Bay
Program.
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Restoring Chesapeake Bay
– Point and non-point sources within the
watershed discharge wastes into the Bay
primarily through rivers that empty into the
Bay.
• A point source of pollution is a discernible
conduit, such as pipes, chimneys, ditches,
channels, sewers, tunnels or vessels, which
transport contaminants.
• A non-point source of pollution is a broad area of
the landscape, such as agricultural fields or
parking lots.
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Restoring Chesapeake Bay
– Chesapeake Bay was the first U.S. estuary selected
for restoration and protection.
– Three major problems requiring immediate attention:
• Over-enrichment of nutrients in Bay waters
• Continued loss of submerged aquatic vegetation
• Pollution by toxic chemicals
– After more than two decades, the accomplishments of
the Chesapeake Bay Program are modest.
• Has helped to prevent environmental conditions in the Bay
from deteriorating as rapidly as they were prior to the 1970s
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Waste Disposal in the Ocean
– The rate of waste production is likely to .keep pace with or
perhaps outpace population growth
– Disposing of waste in an environmentally acceptable
manner is likely to be most challenging in the coastal zone
where the human population is growing at a much more
rapid rate.
– The ocean is viewed as one possible solution to the
problem of waste disposal as terrestrial options are used
up.
– International treaties and national regulations prohibit
ocean disposal of most waste.
• Deliberate discharge of these substances from ships, planes,
and platforms is regulated under the Convention on the
Prevention of Marine Pollution by Dumping of Waste and
Other Matter.
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Waste Disposal in the Ocean
– The ocean is vast and the deep-ocean floor covers
about half of Earth’s surface.
• Our knowledge of this realm is very limited.
• Easy to assume that part of this region could be used for
waste disposal without interfering with other uses of the sea
– Also suggested that we should use the deep ocean
for disposal of nuclear wastes, or carbon dioxide from
industrial chimneys
• We do not yet know nearly enough about the chemistry,
circulation processes, and marine ecosystems in the deep
ocean to be sure that such disposal would be safe and
secure.
– In addition to scientific concerns, ethical issues are
involved in ocean waste disposal.
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Deep-Ocean Carbon Storage
– Schemes to remove carbon dioxide from the
atmosphere or to store it directly instead of releasing
it to the atmosphere have been proposed.
• Replanting tropical forests has been proposed as a
low-cost way to remove atmospheric carbon
dioxide.
• Another potential storage place for carbon dioxide
is in rock formations below the sea floor.
• Other options for sequestration of carbon dioxide
include injection into aquifers, deep coal seams, or
depleted oil reservoir rock.
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Deep-Ocean Carbon Storage
– Ocean iron fertilization (OIF) is
proposed as a means of
boosting the ocean’s uptake of
carbon dioxide from the
atmosphere.
– Ocean scientists have
conducted at least a dozen OIF
experiments since 1993,
releasing a soluble form of iron
into these waters to artificially
stimulate longer-term algal
blooms.
• Carbon dioxide is taken up
from the atmosphere that
would not otherwise be
used in photosynthesis.
© AMS
Large algal bloom off the
coast of Argentina.
Deep-Ocean Carbon Storage
– Open-ocean and deep-ocean ecosystems are too
poorly understood to accurately predict possible
consequences of such iron releases.
– Another option is to inject carbon dioxide directly into
deep-ocean waters for long-term storage.
• CO2 injections at shallow depths were less effective.
• Injections into the deep Pacific Ocean were more successful
than those into the deep Atlantic Ocean.
• Direct injection of carbon dioxide into the ocean is expected
to cause ocean waters to become more acidic with likely
adverse effects on carbonate organisms.
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Obstacles to Ocean Policy
Making
– Agreements required to forge an acceptable
environmental policy at any level of
government are usually complex and fraught
with obstacles and controversy.
• Issues are very often divisive and opposing sides
hold rigid views.
• Political differences sometimes get in the way of
forging agreements on the policies needed to
achieve common goals.
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Obstacles to Ocean Policy
Making
– Problems more complex at international level
– Industrialized nations possessing advanced
technology and many resources to combat pollution
dominate the Northern Hemisphere.
• Environmental damage was done a century or more ago and
is now forgotten or at least partially repaired.
– Developing nations are trying to improve their
economies and reduce poverty by establishing
industries that will create jobs.
• Rush to industrialize and the huge population pressures in
many developing countries have resulted in enormous
pollution problems and damage to ecosystems
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Obstacles to Ocean Policy
Making
– In many developing countries, the attitude is
that economic development must be the top
priority if they are to alleviate widespread
poverty.
– Developed countries blame them for many
pollution and environmental problems.
– Developing countries point to the damage
done in the past by industrialized countries,
and demand financial and technological
assistance if they are to take action on their
own environmental problems.
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Conclusions
– In more recent times, people have begun to become
more aware of issues such as overfishing,
accelerated shoreline erosion, pollution, harmful algal
blooms, oxygen-deficient “dead zones,” and exotic
species invasions.
– Stewardship effort is becoming more urgent as the
human population density in the coastal zone
continues to increase.
– In order for ocean policy to be appropriate and
effective, more resources need to be directed toward
developing a more complete understanding of the
properties and processes of the ocean.
© AMS