Ports in a Storm The volume of global trade has been rising steadily
in the past few years, fueled by free trade
agreements and migration of manufacturing to destinations
in Asia,
particularly China. Nearly 90% of global
trade is by sea, involving a fleet of 45,000 oceangoing
merchant
ships. U.S. ports and waterways move almost
99% of the country’s international trade by
volume and 61% by value, according to America’s
Ports Today, a February 2006 brief from the American
Association of Port Authorities.
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Wakeup call. Ports,
long bustling centers of industry,
have become centers of pollution as
well.
image: Imae Source |
This group estimates that the
volume of cargo American ports currently
handle--about 2 billion tons annually--will double
over the next
15 years. Chinese ports, too, are seeing
a spurt in traffic. China currently has 1,430 ports
and 34,000
docking berths, with a fleet of 210,000
inland and oceangoing vessels capable of handling
more than
86 million tons of cargo, according
to a 7 December 2005 news report from the official
wire agency Xinhua.
According to a 6 March 2006 report
in China Daily, Shanghai is the world’s largest
freight port and the third largest container port.
It handled
443 million tons of cargo and more
than 18 million TEUs (20-foot equivalent units) of
containers in
2005.
While ports are major hubs of
increasing economic activity, they are also increasingly
becoming sources of local and regional pollution.
And as nations around the world grapple with the
health effects of shipping-related pollution,
it becomes apparent that firm regulation is sorely
needed.
Sources of Pollution
For competitive economic reasons, oceangoing vessels
typically use the least expensive (and often the dirtiest)
fuels available. Large diesel engines propel these
vessels, while auxiliary engines provide electric power
for navigation, crew support, and other uses. Diesel-driven
hauling equipment, trucks, and locomotives unload cargo
and then ferry it to faraway inland destinations. Cruise
ships idle at ports, adding to the load of diesel emissions
and noise pollution.
The composition of diesel exhaust--a complex mixture
of combustion products--depends on the type of engine,
the speed and load at which it is run, and the composition
of the fuel used. Diesel exhaust contains identified
mutagens and carcinogens, and diesel exhaust particles
are small enough to penetrate to the alveolar region.
About 98% of the particles emitted from diesel engines
are less than 10 microns in diameter (PM10),
94% are less than 2.5 microns in diameter (PM2.5),
and 92% are less than 1 micron in diameter (PM1).
As a result of incomplete combustion, the gaseous fraction
also contains pollutants such as carbon monoxide, sulfur
oxides (SOx), nitrogen oxides (NOx),
volatile hydrocarbons, and low-molecular-weight polyaromatic
hydrocarbons and their derivatives, according to the
National Toxicology Program.
As one example of the potential for pollution, the
Los Angeles and Long Beach ports of Southern California
together are responsible for daily emissions of 128
tons of NOx, compared to 101 tons from all
6 million cars in the region, according to California’s
South Coast Air Quality Management District. Diesel
PM emissions from the combined ports were estimated
at 1,760 tons per year in 2002 by the California Air
Resources Board (CARB).
This is approximately 21% of the total diesel PM
emissions in the South Coast Air Basin, an area that
includes Orange County and portions of Los Angeles,
Riverside, and San Bernardino counties. Of this, 73%
was emitted by ships in coastal waters extending 14
to 100 miles offshore from California, while commercial
harbor craft accounted for 14% of the total. Other
sources were cargo handling equipment (10%), in-port
heavy-duty trucks (2%), and in-port locomotives (1%).
A projected tripling in trade at the Los Angeles/Long
Beach ports between 2005 and 2020 would result in a
50% increase in NOx emissions and a 60%
increase in PM from trade-related activities, if no
new preventive measures are taken, according to the Goods
Movement Action Plan released by the California
Business, Transportation, and Housing Agency and the
California EPA in December 2005. The plan--basically
a broad statement of the problem and the state’s
intention to take action to mitigate it--projects that
port-related emissions are likely to account for 20%
of total NOx emissions in the South
Coast Air Basin by 2020.
Emissions from ships engaged in international trade
in the seas around Europe--the Baltic, North, Mediterranean,
and Black seas, as well as the northeastern Atlantic--were
estimated to be 2.6 million tons of SOx and
3.6 million tons of NOx a year in 2000,
according to Quantification of Emissions from Ships
Associated with Ship Movements Between Ports in the
European Community, a 2002 study commissioned by
the European Commission (EC). Although emissions from
land-based sources are gradually coming down, those
from shipping are increasing, the report said.
Dredging is a major cause of water pollution in port
environments. Dredging is done routinely to create
and maintain sufficient depth for safe navigation by
ships. The dredged sediments are usually contaminated
by industrial activities occurring in ports and through
deposition of upstream sediments loaded with pollutants
from other land-based sources.
Oil spills--both accidental and otherwise--also contribute
greatly to water pollution. Most water pollution is
a result of waste oil dumping, release of oily bilge
water, washing of oil tankers (oil residue on hull
walls is about 0.5% of the total load, according to
the UN Environment Programme), engine operations, and
the discharge of grease and oils used to maintain engines
and shipboard machinery. Sometimes oily waste is illegally
mixed into ship ballast water to avoid port fees. The
contaminated ballast is then transferred to treatment
plants that are not designed to handle the oily residue.
Ballast water itself is a cause for concern. The
Global Ballast Water Management Programme of the International
Maritime Organization (IMO) estimates that about 3-5
billion tons of ballast water are transferred internationally
each year, often carrying exotic plant species and
disease-causing organisms. A similar volume may also
be transferred domestically within countries and regions
each year. Invasive exotic species can alter the local
ecology, affecting fisheries and threatening endangered
species, besides posing a risk to human health by contaminating
seafood. Fresh- and saltwater ports bear the brunt
of biological invasions introduced by ballast water.
Such invasions are exacerbated when exotics spread
from freshwater ports into rivers and inland lakes.
According to the World Wide Fund for Nature, invasive
species like the North American jellyfish in the Black
Sea, the mitten crab in Europe, and Asian kelp in Australia
have adversely affected commercial fisheries, local
species, and marine habitats. [For more on this topic,
see “Exotic
Invasion,” EHP 105:590-593
(1997)].
Still other shipping-related pollution comes from
ship-breaking/salvage activities. Out-of-service ships
from developed countries are sold to traders for recycling
of metal scrap. “Before Bangladesh, China, India,
and Pakistan became the world’s leading ship-breakers,
vessels were taken apart where they were built: in
industrialized countries,” points out Paul J.
Bailey, a senior technical specialist with the International
Labour Organization. “But high costs and environmental
restrictions have driven ship owners to look elsewhere
for a way of disposing of these vessels.”
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The great catch-all. (left) The Chilean cargo ship Vicuña exploded and
broke in half while unloading ethanol
at a port in Paranaguá, Brazil,
in November 2004. Cleanup workers found
dead fish and dolphins in the toxic
slick of fuel oil, diesel fuel, and
methanol that leaked from the ship.
(above) Ballast water pours into harbor
waters, potentially carrying pathogens,
fuel contaminants, and exotic species.
images: Left to right: Denis Ferreira
Netto/AP; CSIRO scienceimage |
The number of ships to be broken down will go up
in the future, following IMO directives to phase out
all single-hull oil tankers for environmental and safety
purposes. In Europe alone, an estimated 2,200 ships
will go out of service by the year 2010, according
to Greenpeace International. About 1,800 ships from
North America, Brazil, China, and other parts of Asia
will go out of service in the same period.
“Ship-breakers seldom have access to basic
personal protective equipment such as hard hats, gloves,
and goggles for steel-cutting activities,” says
Bailey. “Many are killed and thousands injured
working in often torturous conditions. Titanic-sized
vessels are floated ashore and cut up by workers who
are often exposed to deadly toxicants, exploding gases,
falling steel plates, and other dangers.” In
the December 2005 report End of Life: The Human
Cost of Breaking Ships, Greenpeace and the International
Federation of Human Rights Leagues estimated that the
number of accidental deaths in ship-breaking yards
of Alang in India and Chittagong in Bangladesh could
exceed 100 every year. Furthermore, ships sent for
breaking can contain large quantities of asbestos.
Asbestos fibers were found not only at the ship-breaking
yards at Alang, but in nearby living quarters, waste
dumps, and places of worship. The report cites secondary
data to estimate that 25% of workers in Alang will
develop cancer.
Noise pollution poses further risks. Like air pollution,
noise pollution can affect the cardiovascular system.
Some researchers believe that air and noise pollution
act synergistically. The EC has begun a project to
develop a noise mapping and management system for European
ports with the ultimate objective of reducing noise-related
annoyance and health problems for people living around
ports.
There are two aspects to the noise pollution problem.
The first is the noise produced by diesel-run auxiliary
engines as ships approach ports and idle at dock. In
close proximity to auxiliary engines, noise levels
can reach 80-120 decibels (in comparison, a chain
saw averages 110 decibels). Over the past three decades,
ambient noise levels in a frequency band consistent
with sounds produced by large vessels have increased
at a rate of about 3 decibels per decade at a single
location off Southern California, according to a study
published in the April 2002 issue of Acoustics Research
Letters Online.
The second aspect is the high level of low-frequency
sounds produced by vessels while cruising in the sea.
These sounds can travel long distances and may change
local acoustic environments, impacting marine mammals
that use sound in reproductive interactions and interference
with predator/prey detection. In extreme cases, noise
pollution may cause habitat avoidance in these animals.
Air Toxics: A Particular Concern
The growth in trade and resulting increase in shipping
is impacting the health of workers and people living
in communities near ports and major transport corridors.
Air toxics, in particular, are a source of great concern.
Exposure to diesel PM2.5, along with secondary
particles formed when sulfur dioxide (SO2;
a form of SOx) and NOx react
with ammonia in the atmosphere, is known to cause or
contribute to respiratory diseases, asthma, cardiovascular
disease, lung cancer, and premature death. Emissions
of NOx and reactive organic gases contribute
to the formation of ozone, an oxidant that can damage
the respiratory tract. In 1998, the State of California
listed PM emissions from diesel-fueled engines as a
Toxic Air Contaminant.
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Herculean task. Ship-breakers,
like these workers near Chittagong,
often lack even basic personal protective
equipment, and may encounter hazards
such as asbestos, toxic gases, and
explosions.
image: Heldur Netocny/Panos Pictures |
Current levels of ambient air pollution in Southern
California have been linked to clinically important
chronic health effects, according to a May 2004 study
led by John M. Peters, a professor in the Department
of Preventive Medicine, University of Southern California.
The report, titled Epidemiologic Investigation to
Identify Chronic Effects of Ambient Air Pollutants
in Southern California, was prepared for CARB and
the California EPA. “Our findings demonstrated
effects of air pollution on both new-onset asthma and
asthma exacerbations. Prior to this study, the prevailing
scientific view was that air pollution made existing
asthma worse but that it did not cause new cases to
develop,” says Peters. “We have shown that
air pollution is related to bronchitic symptoms and
that asthmatics are more likely to be affected than
nonasthmatics.” Evaluation of the longitudinal
data implicated nitrogen dioxide, PM2.5,
and organic carbon as being responsible for the observed
effects, he says.
In a study published in the 9 September 2004 issue
of the New England Journal of Medicine, present
Southern California air pollution levels were also
shown to cause chronic adverse effects on lung development
in children from the age of 10 to 18 years, leading
to clinically significant deficits in lung function
as the children reach adulthood. These deficits were
associated with nitrogen dioxide, acid vapor, PM2.5,
and elemental carbon.
Recent findings suggest that chronic health effects
associated with within-city gradients in exposure to
PM2.5 may be even larger than previously
reported across metropolitan areas. In a study published
in the November 2005 issue of Epidemiology,
researchers reported observing effects nearly three
times greater than those seen in earlier studies in
which all the individuals within a given metropolitan
area were assigned the same level of exposure based
on the average ambient concentration observed at fixed
points in that city. In examining specific cause of
death, PM2.5 was associated more strongly
with ischemic heart disease than with cardiopulmonary
or all-cause mortality.
PM in air is also linked with postneonatal mortality,
with respiratory causes having the greatest association.
An EHP study
published online 13 January 2006 found a relationship between postneonatal mortality
from respiratory causes and long-term exposure to PM2.5 in
California (although the study did not specifically
address areas affected by port-related pollution, about
a third of the infants studied were born in Southern
California). Among respiratory deaths, the link was
stronger in low-birth-weight infants as well as those
with bronchopulmonary dysplasia, as an underlying cause
of death. This suggests that these infants and those
infants with underlying lung conditions may be at higher
risk of ill effects from air pollution.
Elsewhere, other major shipping hubs also are realizing
health impacts likely due to marine emissions. In Hong
Kong--home of one of the largest container ports in
the world--marine emissions around Kwai Chung port
are responsible for 36% of total SO2 pollution,
compared to 6% contributed by local coal-fired power
plants. This was one finding that researchers from
Hong Kong University of Science and Technology and
the University of California, Los Angeles, noted in
a 2005 report titled Significant Marine Source for
SO2 Levels in Hong Kong. “Since
the health risks associated with SO2 and
other pollutants such as PM10 are directly
related to the concentration in which they reach sensitive
receivers, the significance of the local marine sources
is of considerable importance for polices to reduce
the health impacts of local air pollution,” the
authors wrote. “Yet, most attention has been
focused on the power plant, while no controls are being
imposed on the quality of fuel oceangoing cargo ships
may burn while in port.”
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Cargo in, cargo
out. (top) Truckers wait to unload
their cargo at the Port of Los Angeles,
adding to the burden of diesel exhaust
borne by port cities. (above) Hundreds
of shipping containers move in a
train at the Port of Los Angeles,
just one way the cargo is moved inland.
images: Top to bottom: Ric Francis/AP; Reed Saxon/AP |
The health risks and impacts due to shipping emissions
from Shanghai’s port have yet to be assessed,
though researchers have studied the impact
of air quality in the city itself. According to an
emission inventory
prepared by the Shanghai Environmental
Monitoring Center, operations at the Port of Shanghai
were responsible
for 44,000 tons of NOx, 39,000 tons of SOx,
and 6,000 tons of PM in 2003.
“We have developed spatial distribution of
emissions, covering internal creeks as well as international
lines along the East China Sea [and] Yangtze River,” says
Dongqing Yang, a team leader at the center. “Since
the air ventilation is so good around the creeks and
river, the air quality in ports is much better than
the urban air quality in Shanghai. Though shipping
emissions are so heavy, the air impact is not so bad
around ports.”
Yang thinks the pollution effect from the Port of
Shanghai is not as serious as it is in California,
saying, “One major reason is large ports are
located along the ocean in the estuary of the Yangtze
River and East China Sea, which are far away from populated
regions. People living near ports suffer more of noise
rather than air pollution.”
Understanding the Impacts
In March 2000, the South Coast Air Quality Management
District published results of the second Multiple Air
Toxics Exposure Study, indicating an overall average
cancer risk in the South Coast Air Basin of about 1,400
per 1 million due to diesel emissions. It indicated
higher risk levels in industrialized areas such as
the south-central portion of Los Angeles County, freeway
interchanges, and areas near air- and seaports. Now
official agencies are beginning to quantify health
impacts of emissions specifically related to port-related
activities.
Of the 9,000 premature deaths reported annually in
California from ambient levels of ozone and PM pollution,
CARB attributes some 8% to emissions from ports and
international goods movement, according to the board’s Draft
Emission Reduction Plan for Ports and International
Goods Movement. The draft CARB plan estimates cancer
risk from diesel PM from all sources to be about 500
to 800 potential cancers per 1 million people exposed
over a 70-year lifetime. A number of health effects--including
heightened risk of heart disease, adverse birth outcomes,
effects on the immune system, multiple respiratory
effects, and neurotoxicity--were not quantified in
the CARB plan due to lack of accepted burden estimates
for those effects.
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Cacophony of
cargo. Noise from large vessels approaching
harbor and idling at the dock adds
to the din of trucks and trains arriving
to transport goods. Added to the
ambient noise of an urban setting,
the cumulative noise can cause health
effects among the population living
nearby.
image: Krista Niles/AP |
According to the draft plan, the largest contributors
to cancer risk and other health effects
are cargo-handling equipment and ships using diesel
engines at dock. These
emissions result in higher calculated risk
due to the emissions’ proximity to residential communities.
Oceangoing vessels, while under propulsion power, produce
far more in the way of emissions but do not result
in a comparable cancer risk since their emissions are
released many miles offshore. However, these vessels’ emissions
are still of considerable concern due to
their potential for contributing to regional air pollution
processes,
says Edward Avol, a professor of clinical
medicine at the University of Southern California Keck
School
of Medicine. These processes include photochemical
formation of a number of pollutants of
health concern, including ozone and PM.
CARB officials have sought peer review of their estimates
of health impacts, and have identified areas in health
assessment analysis that need revision. These areas
include bounding estimates of health impacts of sulfates,
ozone health impact assessment, and additional health
end points such as chronic bronchitis.
Not Yet There
Scientists and action groups feel that CARB’s
health risk assessments are inadequate and narrow in
scope. “It is difficult to measure chronic diseases
epidemiologically,” says John Froines, a professor
of environmental health sciences at the University
of California, Los Angeles. “Given the health
end points including cancer, cardiovascular disease,
neurological, immunological, and developmental disorders,
and allergic airway disease including asthma, it will
be extremely problematic to accurately assess the true
impact of expanded goods movement in coming decades
on the health of exposed populations.”
The CARB assessment, he says, does not address issues
such as occupational exposures, traffic accidents,
psychosocial factors associated with travel, noise,
and light with their implications for cardiovascular
disease. Within air pollution too, the plan has not
looked adequately at a range of end points that are
now known to be important, nor has it attempted to
quantify risks where the end points are indirect.
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Working to contain
the ill effects. A draft plan by
CARB aims to lessen ships’ impact
on premature deaths in California.
image: Lucy Nicholson/AP |
Official projections significantly underestimate
health impacts, says Diane Bailey, an engineer
with the Natural Resources Defense Council. For example,
the CARB plan quantifies health impacts
of shipping
containers as they enter or leave an international
facility, while neglecting to assess pollution
impacts of containers traveling inland to distribution
centers. “Future
health assessments should cover all adverse public
health outcomes, a wider array of pollutants known
to cause adverse health impacts, and all significant
sources known to emit these pollutants,” she
says. “Other issues that must be discussed and
fully incorporated into future analyses
are cumulative risk, increased vulnerability of sensitive
populations,
and risks to exposed workers, besides residential
populations.”
Meanwhile, the shipping industry has questioned the
modeling techniques used to calculate health risks
and maintains that CARB’s risk estimates are
flawed. “There are flaws in the methods used
by CARB and in their application. But we want to make
it clear that the discussion is over the magnitude
of the impacts and not over the fact that there are
impacts that need to be reduced,” says T.L. Garrett,
vice president of the Pacific Merchant Shipping Association. “We
have some concerns on the use of modeling methods to
diagnose health impacts in a population rather than
use of the models to predict relative health benefits
resulting from the implementation of control strategies.”
Regulatory and Technology Issues
Health impacts, including cancer risk, have provided
evidence for stronger regulations aimed at cutting
shipping-related emissions. The CARB plan targets a
20% reduction in diesel PM by 2010 from 2001 levels,
which it claims will reduce health risks by 60% or
more by 2020. “We estimate that one dollar spent
on controls saves four to eight dollars in health costs,” says
Mike Scheible, deputy executive officer at CARB.
“Over half of PM10 and PM2.5,
almost ninety percent of the SOx, and over
a third of the NOx emissions from port
operations are traceable to oceangoing vessels,” says
Avol. “Clearly, substantive reductions in this
source category would have a dramatic effect on regional
air quality and health effects associated with ambient
levels of these pollutants.” He adds, “From
the perspective of proximity to exposure and potential
for noticeable improvements in local community pollution,
trucks, rail, and cruise ships are significant port
sources of pollution. This is because they are emitting
directly in, near, or throughout the immediate community.”
In its first major regulatory step to cut shipping
emissions, CARB has targeted auxiliary engines on ships.
The new rule requires ships to switch over to cleaner-burning
fuels in their auxiliary diesel engines and diesel-electric
engines once they are within 24 nautical miles of the
California coastline. Another new rule targets cargo-handling
equipment such as forklifts and cranes, calling for
replacing or retrofitting their engines with those
using “best available control technology.” The
new regulations, which come into effect 1 January 2007,
are expected to cut diesel PM emissions by a total
of 23,000 tons, NOx emissions by 15,000
tons, and SOx emissions by 200,000
tons by 2020.
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Seeking solutions
in Shanghai. In December 2005, Shanghai
launched operations at the Yangshan
deepwater port, a mammoth facility
more than 20 miles offshore in the
East China Sea. A study of the spatial
distribution of emissions in Shanghai’s
air suggests that placement of ports
farther from populated areas decreases
the health effects of air pollution.
images: Top to bottom: Eugene Hoshiko/AP; INSADCO Photography/Alamy |
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“It is a good start to set goals and list possible
mitigation measures, but as of yet there is really
no plan or strategy,” says Bailey. “For
example, we need to see commitments to
specific details such as mandatory emission reduction
measures rather
than voluntary incentives for industry.
[CARB] needs to be an active regulator of pollution
in our ports
and with regard to goods movement throughout
California.”
The shipping industry has its own doubts about the
CARB rules. Low-sulfur fuels are technically feasible
and are being used by some vessels calling at West
Coast ports, but switching of fuels while under way
(as required under the new rule for auxiliary engines)
raises operational and safety concerns, says Garrett. “The
larger issue is, does the state of California have
the authority to regulate international shipping beyond
its traditional three-mile boundary?” he asks.
The U.S. EPA is working on reducing emissions from
propulsion engines on oceangoing vessels. In 2003,
the agency adopted emission standards for new Category
3 marine diesel engines installed on vessels flagged
or registered in the United States from 1 January 2004
onward. Marine diesel engines differ from other diesel
engines in terms of their exhaust, cooling, electrical,
and fuel systems. Category 3 engines are large diesel
engines used for propulsion power on container ships,
tankers, bulk carriers, and cruise ships. These standards
will apply until a second tier of standards for deeper
emission reductions is developed; these standards should
be finalized by April 2007. In the future, these standards
may be made applicable to engines on foreign vessels
entering U.S. ports. The EPA also intends to eventually
set standards for fuels used by marine engines.
The federal agency estimates that these regulations--when
fully implemented in 2030--will annually prevent up
to 12,000 premature deaths, 15,000 heart attacks, and
6,000 child asthma-related emergency room visits throughout
the United States.
Because issues such as engine emissions and fuel
standards are international in scope, the IMO is also
framing rules for cutting down shipping emissions.
In May 2005, an IMO regulation on engine emission standards
for NOx came into force for engines above
130 kilowatts, in the form of Annex VI of the International
Convention for the Prevention of Pollution from Ships.
The rule includes a global cap of 4.5% by mass on sulfur
content of fuel oil and recommends monitoring of sulfur
content globally. (However, considering that the rolling
average of sulfur content globally from 2002 through
2004 was 2.67%, the new cap may be too liberal.) The
IMO is also encouraging countries to declare their
coastlines as “SOx Emission Control
Areas” (SECAs), where sulfur content in fuel
must not exceed 1.5%. The U.S. EPA is exploring a potential
North American SECA.
Under the marine fuel directive adopted by the European
parliament in April 2005, all ships in the Baltic SECA
and passenger vessels in European Union (EU) territorial
waters will have to use fuel with a 1.5% sulfur limit
after 11 August 2006. The 1.5% sulfur limit will apply
to the North SECA (which includes the English Channel)
after 11 August 2007. The sulfur limit will be 0.1%
in fuel used by passenger vessels and seagoing ships
at berth in EU ports after 1 January 2010. These measures
are expected to reduce shipping-related SO2 in
the EU by over 500,000 metric tons a year from 2006.
Besides marine fuel regulation, the EC is encouraging
research to assess the economic and technical feasibility
of SOx and NOx abatement technologies
such as shoreside electricity, seawater scrubbing,
selective catalytic reduction, and the use of humid
air motors. The EC also favors fiscal incentives and
voluntary measures to encourage the use of low-sulfur
fuels and green technologies by ship owners. But even
after the implementation of SECAs in Europe, SOx emissions
from international shipping are projected to grow by
42% and NOx emissions to grow by 60% by
2020. By then, emissions from international shipping
around Europe will have surpassed the total from all
land-based sources in the 25 member states combined,
according to the 2005 report Baseline Scenarios
for the Clean Air for Europe (CAFE) Programme.
Another emission reduction strategy is to cut idling
time of vessels and tugboats by providing electric
power on shore. The Port of Los Angeles has signed
a lease with container terminal operator P&O Nedlloyd
that would require the company to use shore power for
ships at berth and alternative fuel yard tractors,
and possibly employ low-sulfur fuel in vessel main
engines. An additional benefit of using shoreside electricity
is the elimination of noise and vibration from the
auxiliary engines while they are at berth. At Sweden’s
Port of Göteborg, shoreside power is sourced from
wind turbines, thus foiling criticism that the use
of land-sourced power is merely switching from one
dirty fuel to another.
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Night-owls
reduce NOx. The twin ports of Los
Angeles and Long Beach have begun
operating on weekends and evenings
in a new initiative designed to cut
freeway congestion and emissions.
image: Chris Carlson/AP |
Plugging in to onshore power requires retrofitting
power systems or ships, and that involves new investments;
it may not be economically viable for infrequent visitors.
Nearly 20% of the ships visiting California ports will
use shore-based power by 2010. This number would gradually
go up to 80% by 2020, according to CARB. Avol points
out this is only a proposed strategy at the present
time, however, and it remains to be seen how realistic
it would be in practice.
Reducing the speed of vessels as they approach a
port can also help cut emissions. About 70% of ships
calling at the ports of Los Angeles and Long Beach
participate in a voluntary speed reduction program
implemented since 2002. The plan requires ships to
reduce their speed from 22 knots to 12 knots or less
within a 20-mile radius of the two ports. The strategy
is sweetened by a financial incentive; operators qualify
for a 15% discounted dockage rate during the following
12 months if 90% of their vessels comply with the 12-knot
speed limit for a year.
In the first six months of 2005, speed reduction
at the Port of Los Angeles saved 266 tons of NOx emissions.
The port now plans to extend the limit to 40 nautical
miles. Authorities at the Port of Long Beach estimate
that if all vessels comply with the program, the amount
of NOx produced by container ships
would be cut by about 550 tons a year. One potential
drawback to this scheme is that if ships are going
to take longer to reach their destination ports, it
can impact ship schedules.
Recycling of waste oil, oily bilge, and oil-contaminated
waste can go a long way toward minimizing oil pollution
at ports. In the 2000 report Green Ports: Environmental
Management and Technology at U.S. Ports, researchers
at the University of Massachusetts Boston Urban Harbors
Institute recommended that ports provide facilities
for oil collection and recycling that are easily accessible
and inexpensive. Oil-dispensing facilities at ports
can be encouraged to buy back used oil for recycling.
Runoff from parking areas and roads that pick up oil
and other wastes from land can be controlled quite
effectively through filtration devices such as porous
pavements, soak-away pits, and dry wells.
Main issues that need to be resolved to check shipping
pollution are international and national consensus
on fuel quality, emission standards, and a time frame
for adoption as well as for onshore power systems.
There is a need to enforce the same for other contributors
to diesel emissions--cargo-handling equipment, trucks,
and locomotives. For this exercise to succeed, engine
makers and oil companies also need to be involved.
In many parts of the world, shipping-related emissions
have already exceeded or are projected to exceed those
from land-based sources in the next few years, if no
reduction measures are taken. Shipping emissions can
be cut substantially by deploying some of the same
technologies and fuels used for cutting emissions from
land-based mobile and stationary sources. But doing
so poses major economic, legal, and infrastructural
challenges.
The emission reduction strategies currently on the
table revolve around cleaner engines, cleaner fuels,
exhaust control methods, and operational programs.
And a variety of mechanisms are being explored or have
been proposed to implement these strategies. The feasibility
of these mechanisms is being tested at various ports
with varying degree of success. What is needed is expedited
decision making at all levels, from IMO to port city
authorities, to ensure that our ever-increasing need
to trade, transfer, and transport various things around
the globe doesn’t leave all of us stranded on
an environmental ship of fools.
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