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The maritime industry, a significant contributor to marine pollution, generates millions of tons of garbage daily, impacting the marine ecological system. The shipping industry, a primary source of sea pollution, has been addressed by the MARPOL Convention since 1973, covering oil, noxious substances, harmful packaged substances, sewage, garbage, and air pollution prevention. MARPOL has substantially reduced international shipping pollution, encompassing 99% of global merchant tonnage. Additional agreements target anti-fouling systems, ballast water transfer, and ship recycling. Despite the industry’s vast growth, pollution decline results from addressing technical, operational, and human factors.

POLLUTION BY DISCHARGE OF OILS AND CHEMICALS

Oil Pollution

oil pollution 1

Annually, oil tankers transport about 2,900 million tonnes of crude oil and oil products, posing a significant source of marine pollution. Extensive oil spills led to the establishment of IMO regulations for marine environmental protection. MARPOL regulations ensure the safe construction and operation of oil tankers, reducing spillage risks. Both construction and operational requirements have resulted in a decline in unintentional oil pollution over the past 30 years. MARPOL, introduced in 1983, mandated innovations like segregated ballast tanks and, later, double hulls for oil tankers, significantly enhancing marine environmental protection. Operational oil pollution has decreased due to MARPOL’s modifications on permissible discharges, contributing notably to reducing sea pollution.

Chemical Pollution

chemical pollution

Chemicals pose significant environmental concerns in the marine environment, particularly oil, toxic metals, and persistent organic pollutants. Regulations for the carriage of chemicals by ships are outlined in the SOLAS and MARPOL Conventions. The International Bulk Chemical Code (IBC Code) sets international standards for the safe bulk carriage of dangerous chemicals, applicable to tankers constructed after July 1, 1986. For tankers built before this date, compliance with the Code for the Construction and Equipment of Ships Carrying Dangerous Chemicals in Bulk (BCH Code) is required. MARPOL Annex II categorizes noxious liquid substances in bulk, defining their hazards and regulating their discharge into the sea. The Annex also specifies discharge levels and residue limits for modern stripping techniques. Chemicals carried in packaged form, whether solid or bulk, are regulated by SOLAS Chapter VII and MARPOL Annex III, addressing dangerous goods’ classification, packing, marking, labeling, documentation, and stowage. Both conventions refer to the International Maritime Dangerous Goods (IMDG) Code, developed by the IMO as a uniform international code for the sea transport of dangerous goods.

DANGEROUS GOODS, SEWAGE AND GARBAGE

Dangerous Goods

dangerous goods

Dangerous goods in the shipping industry are substances that, if mishandled, pose a risk to people or the environment. The revised MARPOL Annex III focuses on preventing pollution by harmful substances in packaged form. It defines harmful substances as those identified in the IMDG Code or meeting specific criteria. The Annex outlines requirements for packing, marking, labeling, documentation, stowage, quantity limitations, and port State control to prevent pollution. It prohibits jettisoning harmful substances except in emergencies for ship safety or saving lives at sea.

Sewage

sewage

Discharging raw sewage into the sea poses significant health risks and environmental problems, impacting oxygen levels and coastal aesthetics, particularly in tourist-dependent countries. While land-based sources are major contributors, ships directly discharging sewage contribute to marine pollution. MARPOL Annex IV addresses sewage pollution from ships, mandating ships over 400 gross tonnage or certified for over 15 passengers to have sewage treatment systems, commuting and disinfecting systems, or holding tanks. The Annex establishes discharge standards to mitigate environmental impact, emphasizing the importance of regulating sewage disposal at sea to protect coastal ecosystems and public health.

Garbage

garbage 1

Ship garbage, particularly plastic, poses a significant threat to marine life, leading to ingestion and entanglement. MARPOL Annex V addresses marine pollution by garbage, generally prohibiting discharge into the sea, except for specific cases like safety, life-saving, or accidental loss due to ship damage. The Annex expressly bans plastic disposal at sea unless under special circumstances, emphasizing the need to curb marine pollution and protect aquatic ecosystems.

AIR POLLUTION

air pollution

Commercial ships contribute to air pollution by emitting various pollutants during fuel combustion. The marine shipping industry accounts for approximately 2.2% of global carbon dioxide, 15% of nitrogen oxides, and 13% of sulfur oxides emissions annually. To address this, MARPOL Annex VI, introduced in 1997 and revised in 2010, regulates airborne emissions, focusing on sulfur (SOx), nitrogen oxides (NOx), ozone-depleting substances (ODS), and volatile organic compounds (VOCs). The revised Annex mandates a progressive reduction of sulphur content in fuel and introduces emission control areas with stricter limits. It also requires tankers to employ vapor emission control systems and implement VOC Management Plans. The Annex prohibits deliberate emissions of ODS and shipboard incineration of certain substances. Furthermore, it outlines regulations for fuel oil quality, availability, and reception facilities for ozone-depleting substances. These measures aim to minimize the environmental impact of air pollution from the shipping industry.

Energy Efficiency

energy efficiency

Enhanced energy efficiency in shipping involves using less fuel, leading to reduced environmental emissions. In 2011, the International Maritime Organization (IMO) implemented mandatory technical and operational energy efficiency measures (EEDI/SEEMP) to curb CO2 emissions from international shipping. These measures, effective since January 1, 2013, aim to decrease greenhouse gas emissions. IMO provides guidelines supporting the implementation of these measures, fostering the adoption by administrations and the industry. Considering the anticipated growth in world trade, IMO is exploring additional technical and operational measures to enhance the energy efficiency of ships further.

Reduction of GHG Emissions from Ships

reduction of ghg emissions from ships

The maritime industry accounted for approximately 3.3% of global greenhouse gas (GHG) emissions in 2007, with international shipping contributing around 2.7% of global CO2 emissions. Without intervention, emissions from the maritime sector could surge by 150–250% by 2050. Despite being a relatively efficient means of mass transport, global efforts to enhance energy efficiency and emission control in international shipping are essential due to its anticipated growth. The 1997 Kyoto Protocol encourages states to limit or reduce GHG emissions from bunker fuels through the International Maritime Organization (IMO), acknowledging maritime operations’ global and complex nature.

POLLUTION PREPAREDNESS AND RESPONSE

responding to marine pollution incidents

The International Convention on Oil Pollution Preparedness, Response, and Co-operation (OPRC Convention), established in 1990, aims to enhance preparedness, response, and cooperation for oil pollution incidents. State parties must develop National Oil Pollution Contingency Plans (NOPCP) and instruct their ships to carry Shipboard Oil Pollution Emergency Plans. Offshore units within a State’s jurisdiction must have coordinated Oil Pollution Emergency Plans. Coastal authorities, ports, and handling facilities must have contingency plans and facilities. The OPRC Convention mandates prompt reporting of pollution incidents by ships to coastal authorities. The 2000 Protocol expanded the Convention’s scope to include hazardous noxious substances beyond oil, emphasizing international collaboration in addressing pollution emergencies.

Preparing for Marine Pollution Incidents

preparing for marine pollution incidents

Efficient marine pollution response requires continuous planning and adjustment to address evolving risks from shipping, offshore activities, and handling. The OPRC 90 and OPRC-HNS Protocol mandate readiness and response systems. Contingency planning must involve ongoing development, adjustment, and training to ensure preparedness and capabilities. This includes assigning roles, detailing response strategies and procedures, and providing training to enhance knowledge and skills. A well-structured planning process supports decision-makers in executing appropriate response strategies, mobilizing resources effectively, and managing incident consequences. Planning remains crucial in addressing the dynamic challenges of marine pollution incidents.

Responding to Marine Pollution Incidents

Responding to marine pollution incidents demands specialized knowledge, expertise, and dedicated equipment. The OPRC 90 and OPRC-HNS Protocol 2000 establish global legal standards for oil and hazardous noxious substances (HNS) pollution preparedness and response. The Intervention Convention, born out of the 1967 Torrey Canyon disaster, grants coastal states the right to take necessary measures on the high seas to prevent, mitigate, or eliminate oil pollution dangers to their coastlines. This right is subject to consultation with relevant parties, and intervention requires demonstrating a ‘grave necessity’. Any unlawful intervention leads to liability for compensation. A 1973 Protocol expanded its scope to cover substances beyond oil.

BALLAST WATER MANAGEMENT

introduction ballast

Besides vessel-source pollution, maritime transportation introduces additional threats to the marine environment. Transferring harmful aquatic organisms through ballast water and introducing invasive species through bio-fouling are notable concerns. Ships use ballast water for stability, often discharging it in ports, potentially spreading invasive species. Bio-fouling, the attachment of marine organisms to vessel surfaces, is another significant mode of transportation for these species. Invasive aquatic species, once introduced, can rapidly proliferate, outcompete native species, and alter ecosystems. Beyond fish and invertebrates, invasive species may include parasites, viruses, bacteria, and other microorganisms, severely threatening aquatic environments and native ecosystems. This underscores the importance of effective measures to prevent and manage bio-invasions in maritime activities.

Management of Ship’s Ballast Water

The Ballast Water Management Convention, enacted in 2004, aims to prevent the transfer of harmful aquatic organisms across different regions. It establishes standards and procedures for managing ships’ ballast water and sediments. All international vessels must adhere to specific ballast water management standards, maintain a ship-specific plan, keep a ballast water record book, and hold an international ballast water management certificate. The convention is being implemented gradually, requiring most ships to eventually install on-board ballast water treatment systems, with mid-ocean ballast water exchange serving as a temporary 

SPECIAL AND PARTICULARLY SENSITIVE SEA AREAS

MARPOL specifies certain sea areas as “special areas” in which, for technical reasons regarding their oceanographical and ecological condition and to their sea traffic, the adoption of special mandatory methods for the prevention of sea pollution is required. Under the Convention, these special areas are provided with a higher level of protection than other sea areas.

Adoption, Entry into force & Date of taking effect of Special Areas

Special Areas

Adopted #

Date of Entry into Force

In Effect From

Annex I: Oil

Mediterranean Sea

2 Nov 1973

2 Oct 1983

2 Oct 1983

Baltic Sea

2 Nov 1973

2 Oct 1983

2 Oct 1983

Black Sea

2 Nov 1973

2 Oct 1983

2 Oct 1983

Red Sea

2 Nov 1973

2 Oct 1983

 

“Gulfs” area

2 Nov 1973

2 Oct 1983

1 Aug 2008

Gulf of Aden

1 Dec 1987

1 Apr 1989

 

Antarctic area

16 Nov 1990

17 Mar 1992

17 Mar 1992

North West European Waters

25 Sept 1997

1 Feb 1999

1 Aug 1999

Oman area of the Arabian Sea

15 Oct 2004

1 Jan 2007

 

Southern South African waters

13 Oct 2006

1 Mar 2008

1 Aug 2008

Annex II: Noxious Liquid Substances

Antarctic area

30 Oct 1992

1 Jul 1994

1 Jul 1994

Annex IV: Sewage

Baltic Sea

15 Jul 2011

1 Jan 2013

 

Annex V: Garbage

Mediterranean Sea

2 Nov 1973

31 Dec 1988

1 May 2009

Baltic Sea

2 Nov 1973

31 Dec 1988

1 Oct 1989

Black Sea

2 Nov 1973

31 Dec 1988

 

Red Sea

2 Nov 1973

31 Dec 1988

 

“Gulfs” area

2 Nov 1973

31 Dec 1988

1 Aug 2008

North Sea

17 Oct 1989

18 Feb 1991

18 Feb 1991

Antarctic area (south of latitude 60 degrees south)

16 Nov 1990

17 Mar 1992

17 Mar 1992

Wider Caribbean region including the Gulf of Mexico and the Caribbean Sea

4 Jul 1991

4 Apr 1993

1 May 2011

Annex VI: Prevention of air pollution by ships (Emission Control Areas)

Baltic Sea (SO)

(NOx)

26 Sept 1997

7 July 2017

19 May 2005

1 Jan 2019

19 May 2006

1 Jan 2021

North Sea (SOx)

(NOx)

22 Jul 2005

7 July 2017

22 Nov 2006

1 Jan 2019

22 Nov 2007

1 Jan 2021

North American ECA
(SOx and PM)

(NOx)

26 Mar 2010

1 Aug 2011

1 Aug 2012

1 Jan 2016

United States
Caribbean Sea ECA
(SOx and PM)

 (NOx)

26 Jul 2011

1 Jan 2013

1 Jan 2014

1 Jan 2016***

 Particularly Sensitive Sea Area

particularly sensitive sea area

Particularly Sensitive Sea Areas (PSSAs) merit special protection due to their ecological, socio-economic, or scientific significance, vulnerable to potential harm from international maritime activities. PSSA designation criteria overlap with those for Special Areas, and an area may be both. Designated PSSAs include the Great Barrier Reef, Sabana-Camagüey Archipelago, Malpelo Island, Florida Keys, Wadden Sea, Paracas National Reserve, Western European Waters, Torres Strait extension, Canary Islands, Galapagos Archipelago, Baltic Sea, Papahānaumokuākea Marine National Monument, Strait of Bonifacio, Saba Bank, Coral Sea extension, Jomard Entrance, and Tubbataha Reefs Natural Park. These designations emphasize the importance of safeguarding diverse marine ecosystems through international cooperation and regulatory measures.

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