World Nautical Chart

Introduction

A world nautical chart provides a global representation of the world's oceans and major maritime regions. It is primarily a reference document for visualising the main ocean areas, continents, major shipping routes and navigation regions on a worldwide scale.

A world nautical chart is particularly useful for planning a circumnavigation, studying an ocean passage, analysing a maritime route or simply understanding global maritime geography. It makes it possible to locate the major oceans — Atlantic, Pacific, Indian, Arctic and Southern Oceans — as well as the principal seas associated with them.

Unlike a coastal nautical chart or harbour approach chart, a world chart focuses on the overall picture. Its scale generally does not allow the detailed information required for navigation in a channel, passage, anchorage or harbour. It therefore serves primarily for general planning and geographical representation.

What Is a World Nautical Chart?

A world nautical chart represents a very large portion of the globe on a single sheet or within a single cartographic document. Depending on its purpose, it may show oceans, continents, major islands, major shipping routes, selected depths or bathymetric contours and various geographical reference points.

The term “world nautical chart” can refer to several types of documents depending on their intended use:

• general-purpose nautical world chart;

• world ocean chart;

• nautical chart for planning major ocean passages;

• very small-scale ocean chart;

• world chart showing major shipping routes;

• world chart intended for circumnavigation planning.

The choice of cartographic projection is also important. Representing the curved surface of the Earth on a flat sheet inevitably creates distortions. A world chart designed for navigation therefore does not necessarily have the same characteristics as a general geographical world map.

The Five Major Oceans

A world nautical chart makes it possible to visualise the five major oceans.

The Atlantic Ocean separates Europe and Africa from the Americas. It includes the North Sea, Baltic Sea, Norwegian Sea, Caribbean Sea, Labrador Sea and Gulf of Mexico.

The Pacific Ocean is the largest ocean in the world. It extends between Asia, Oceania and the western coasts of the Americas. It includes the Bering Sea, Sea of Okhotsk, Sea of Japan, Philippine Sea, Coral Sea and Tasman Sea.

The Indian Ocean lies between Africa, Asia, Australia and Antarctica. It includes the Arabian Sea, Bay of Bengal, Andaman Sea and Mozambique Channel.

The Arctic Ocean surrounds the North Pole and connects with the Atlantic and Pacific Oceans. It includes the Barents Sea, Kara Sea, Laptev Sea, Beaufort Sea and Chukchi Sea.

The Southern Ocean surrounds Antarctica and represents a major area for southern-ocean navigation and scientific expeditions.

Major Global Shipping Routes

One of the main advantages of a world nautical chart is the ability to visualise the major shipping routes connecting the continents.

North Atlantic routes connect Europe with North America. They serve major ports such as Rotterdam, Hamburg, Le Havre, Southampton, New York, Baltimore and Halifax.

In the South Atlantic, routes connect Europe, southern Africa and South America. Ports such as Dakar, Cape Town, Rio de Janeiro, Santos, Montevideo and Buenos Aires are important reference points.

In the Indian Ocean, shipping routes connect Europe and the Middle East with Asia. Ports such as Djibouti, Salalah, Mumbai, Colombo, Singapore and Durban illustrate the importance of this maritime region.

In the Pacific, routes connect Asia, Oceania and the Americas. Tokyo, Shanghai, Singapore, Sydney, Auckland, Vancouver, Los Angeles and San Francisco are major maritime hubs.

A Useful Chart for Circumnavigation Planning

For a navigator planning a round-the-world voyage, a world chart is particularly useful during the initial planning stage.

It makes it possible to visualise the major stages of an itinerary and compare different ocean routes. A circumnavigation can therefore be represented as a route crossing the Atlantic, transiting the Panama Canal, crossing the Pacific, continuing through the Indian Ocean, passing through the Suez Canal and returning to the Mediterranean.

A world chart also helps to understand the relative position of major straits and canals:

• Strait of Gibraltar;

• Panama Canal;

• Strait of Magellan;

• Suez Canal;

• Bab-el-Mandeb Strait;

• Strait of Hormuz;

• Strait of Malacca;

• Torres Strait;

• Bering Strait.

These passages play an important role in the geography of global maritime routes.

Ports and Major Maritime Hubs

A world nautical chart can also be used to locate the world's principal ports.

In Europe, Rotterdam, Antwerp, Hamburg, Le Havre, Marseille and Genoa are major maritime references.

In Asia, Singapore, Shanghai, Hong Kong, Busan, Tokyo, Yokohama and Colombo play important roles in international shipping networks.

In North America, the ports of New York, Norfolk, Houston, Los Angeles, Long Beach, Vancouver and Seattle are major maritime hubs.

In South America, Santos, Rio de Janeiro, Buenos Aires, Montevideo, Valparaíso and Callao help identify the continent's principal maritime routes.

In Africa, Durban, Cape Town, Mombasa, Dar es Salaam, Tanger Med, Casablanca, Lagos and Abidjan are important reference points for understanding maritime routes around the continent.

Major Chart Publishers and Hydrographic Services

Global maritime charting relies on a network of national hydrographic services and international organisations.

Shom, the French Hydrographic and Oceanographic Service, has a catalogue covering the oceans and numerous maritime regions worldwide. Its catalogue includes general charts, ocean and passage charts, coastal charts, as well as harbour and anchorage charts.

Admiralty, produced by the United Kingdom Hydrographic Office, is also an important international reference for maritime charting. Its coverage includes numerous ocean routes, coastlines and port areas around the world.

NGA, the National Geospatial-Intelligence Agency, also provides worldwide maritime chart coverage. Its Digital Nautical Chart system covers the major maritime regions of the globe and includes charts at different scales.

Other organisations also play an important role depending on the region, including NOAA in the United States, the Australian Hydrographic Office in Australia, LINZ in New Zealand, the Canadian Hydrographic Service in Canada and the various European and Asian hydrographic services.

World Chart and Cartographic Scale

Scale is fundamental to understanding how a world nautical chart can be used.

A very small-scale chart can represent a huge area, but the amount of detail is necessarily limited. It is therefore suitable for general planning.

Conversely, a large-scale chart covers a much smaller area but represents depths, dangers, buoys, channels and harbour infrastructure in much greater detail.

Shom, for example, distinguishes between “Oceans and Passages”, “Coastal Charts” and “Harbours and Anchorages” in its catalogue, illustrating the complementary nature of different cartographic levels.

A world chart therefore does not replace a detailed navigational chart. It represents the first level of geographical planning before moving to regional, coastal and harbour charts.

Paper World Charts and Digital Cartography

A world chart can exist in paper or digital form.

A paper chart provides an immediate and global representation of the world's maritime geography. It is particularly useful for working on a general route, visualising distances and understanding the relationship between different oceans.

A digital representation may take the form of a raster or vector chart. Digital data can then be used to work with different zoom levels and geographical areas.

In digital cartography, vector data and ENCs allow a more interactive representation of navigational information. Modern systems can display different chart objects depending on the scale and zoom level.

Using a World Chart to Plan a Maritime Route

A world chart can be used as the first stage of navigation planning.

The navigator can begin by identifying:

• the departure and destination points;

• the oceans to be crossed;

• possible ports of call;

• straits and canals to be transited;

• major ocean distances;

• geographical areas requiring more detailed charts;

• the different stages of a circumnavigation.

Once this overall view has been established, ocean, regional, coastal and harbour charts progressively take over.

This approach creates a genuine cartographic hierarchy: global overview, ocean passage planning, regional navigation, coastal approach and finally harbour navigation.

Conclusion

A world nautical chart is primarily a tool for obtaining a global view of maritime geography. It allows navigators to locate the five oceans, major seas, principal shipping routes, straits, canals and major ports.

For offshore sailors, cruisers planning a circumnavigation or anyone wishing to understand the organisation of the world's maritime spaces, a world chart provides a particularly useful overview.

It does not replace the detailed charts required for navigation, but provides their logical complement during the planning phase. Charts from Shom, Admiralty, NGA and the various national hydrographic services can then be used to move progressively from a global representation to charting appropriate for each stage of a voyage.

FAQ – World Nautical Chart

What is a world nautical chart used for?

It is primarily used to visualise the world's oceans and major maritime regions, plan an ocean route or prepare a circumnavigation.

Can a world nautical chart be used for coastal navigation?

Generally not. Its scale is too small to provide the level of detail required for precise coastal navigation. It should be supplemented by coastal and approach charts.

Which oceans are shown on a world nautical chart?

A world nautical chart can represent the Atlantic Ocean, Pacific Ocean, Indian Ocean, Arctic Ocean and Southern Ocean.

What is the difference between a world chart and an ocean chart?

A world chart provides a global or near-global view. An ocean chart covers a more limited area and generally provides more detail for planning an ocean passage.

Is a world chart useful for planning a sailing circumnavigation?

Yes. It allows the navigator to visualise the different oceans to be crossed, major ports of call, canals and straits, as well as the overall structure of the itinerary.

Which publishers produce nautical charts covering the world's oceans?

Shom, Admiralty/UKHO and NGA are among the major international maritime charting organisations, supplemented by national hydrographic services according to geographical area.

Which major ports can be located on a world nautical chart?

Depending on the document and its level of detail, major ports may include Rotterdam, Le Havre, Singapore, Shanghai, Tokyo, Mumbai, Durban, Cape Town, New York, Los Angeles, Sydney, Auckland, Rio de Janeiro and Buenos Aires.

What is the difference between a paper and digital world nautical chart?

A paper chart provides a physical and global representation. A digital version generally allows interaction with the data, adjustment of the zoom level and work with different chart layers or geographical areas depending on the system used.

Does a world nautical chart show water depths?

Some world or ocean charts show bathymetric information or depth contours, but the level of detail is limited by the scale. Coastal and harbour charts are required for precise depth information.

Which chart should be used after a world chart when planning navigation?

After establishing the global overview, the navigator generally selects an ocean or passage chart, followed by regional, coastal and approach charts according to the route.

Why use a world chart for circumnavigation planning?

It provides an overall view of the itinerary and makes it possible to visualise the relationship between the different oceans, continents, archipelagos, canals and straits before working with larger-scale charts.