Pacific Ocean Nautical Charts

Introduction

A Pacific Ocean nautical chart is an essential document for planning an ocean crossing, offshore passage, circumnavigation or coastal navigation in the largest ocean in the world. The Pacific extends between Asia, Oceania and the western coasts of North and South America. It contains thousands of islands, archipelagos, reefs, atolls and maritime areas with very different navigational characteristics.

A Pacific Ocean nautical chart represents depths, shoals, reefs, wrecks, isolated dangers, lights, buoys and other aids to navigation, as well as coastal and harbour approaches. Depending on its scale, it can be used to plan a passage of several thousand nautical miles or to navigate accurately near an island, reef or port.

Pacific nautical charts are available in different formats: paper charts, raster charts, vector charts and Electronic Navigational Charts (ENCs). The choice depends on the route, geographical area, type of navigation and level of detail required.

The Main Areas Covered by Pacific Ocean Nautical Charts

The immense size of the Pacific means that it must be considered as several major charting regions. The main areas include:

• the North Pacific;

• the South Pacific;

• the Central and Eastern Pacific;

• the Bering Sea;

• the Sea of Okhotsk;

• the Sea of Japan;

• the Philippine Sea;

• the South China Sea;

• the Celebes Sea;

• the Banda Sea;

• the Solomon Sea;

• the Coral Sea;

• the Tasman Sea;

• the western coasts of North America;

• the western coasts of South America;

• Japan and East Asia;

• Australia and New Zealand;

• Melanesia, Micronesia and Polynesia.

This geographical organisation is important when selecting the appropriate charts for each stage of a Pacific voyage.

North Pacific, Japan and East Asia

The North Pacific is a vast navigation area connecting North America and Asia. Nautical charts for this region cover the coasts of Japan, eastern Russia, Korea, China and the approaches to numerous Pacific archipelagos.

Navigators may need to plan routes to ports such as Tokyo, Yokohama, Osaka, Kobe, Nagoya, Busan, Shanghai, Qingdao or Vladivostok.

The Sea of Japan, Sea of Okhotsk and Philippine Sea have different cartographic characteristics. A chart intended for an ocean passage does not provide the same level of detail as a coastal or harbour approach chart.

In this region, charts produced by Admiralty, NGA and the Japanese, Korean, Chinese or Russian hydrographic services may be relevant depending on the area concerned.

Western Pacific and Southeast Asian Seas

The western Pacific includes a succession of seas and archipelagos that are particularly complex from a navigational perspective.

The South China Sea, Philippine Sea, Celebes Sea, Banda Sea and Solomon Sea are connected to numerous commercial and inter-island routes.

This region includes the Philippines, Indonesia, Papua New Guinea and the archipelagos of Melanesia.

Navigators must distinguish between general route planning and navigation in coastal areas. The numerous islands, passages, reefs, channels and shoals may require large-scale charts.

Ports such as Manila, Cebu, Davao, Port Moresby and Lae illustrate the diversity of port environments in this part of the Pacific.

Coral Sea, New Caledonia and Australia

The Coral Sea occupies a central position for navigation between Australia, New Caledonia, the Solomon Islands and the archipelagos of the South Pacific.

This region includes the Great Barrier Reef of Australia, whose complexity requires appropriate charting for coastal navigation and reef approaches.

Ports such as Brisbane, Sydney, Cairns, Darwin and Fremantle may form part of an Australian sailing route or a Pacific crossing.

Further east, New Caledonia is an important stop for navigators travelling between Australia and Polynesia or New Zealand. Nouméa and the numerous islands and passages of the archipelago require charts suitable for coastal navigation.

The Australian Hydrographic Office (AHO) produces many charts covering Australian waters, while Shom and Admiralty also provide chart coverage for various Pacific regions.

French Polynesia and the South Pacific

The South Pacific is particularly important for offshore cruising and sailing routes following the trade winds.

French Polynesia includes the Society Islands, Tuamotu Archipelago, Marquesas Islands and Austral Islands. Islands such as Tahiti, Raiatea, Huahine, Taha'a, Bora Bora, Rangiroa, Fakarava, Tubuai and Rapa have very different geographical configurations.

In coral archipelagos, accurate charting is essential. Navigators need to be able to identify reefs, passes, lagoons, shoals, channels and isolated dangers.

Shom provides significant coverage of French Polynesia, including charts dedicated to Polynesian islands and archipelagos. Admiralty charts also cover various routes and areas of the South Pacific.

Fiji, Tonga, Vanuatu, Samoa and New Zealand

Further west and south-west of Polynesia lie the archipelagos of Fiji, Tonga, Vanuatu and Samoa.

Routes between these islands can extend over several hundred nautical miles and require a combination of ocean and more detailed approach charts.

Ports such as Suva, Port Vila, Nuku'alofa and Apia are important reference points for regional navigation.

New Zealand then represents a major charting area, particularly around Auckland, Wellington, Tauranga and Lyttelton. Charts produced by LINZ, Land Information New Zealand, cover New Zealand waters and complement international chart coverage.

Major Chart Publishers and Hydrographic Services

Several organisations produce nautical charts covering the Pacific.

Shom, the French Hydrographic and Oceanographic Service, provides significant Pacific coverage, particularly around French territories and French Polynesia. Shom charts may cover ocean passages, coastal navigation and detailed approaches.

Admiralty, published by the United Kingdom Hydrographic Office, is an important international reference for offshore navigation and maritime routes throughout the Pacific. Some series cover the Tasman and Coral Seas as well as routes between Australia, New Zealand and the Pacific islands.

NGA, the National Geospatial-Intelligence Agency, also provides extensive Pacific coverage, particularly for international and offshore navigation.

The Australian Hydrographic Office, Canadian Hydrographic Service and Land Information New Zealand also contribute to charting within their respective national waters. NOAA provides chart coverage for US Pacific waters, including the west coast of the United States, Alaska and relevant territories.

Paper, Raster and Vector Nautical Charts

The choice of format depends on the type of navigation.

Paper nautical charts remain particularly useful for planning a passage, viewing the overall route and maintaining an independent reference alongside electronic equipment.

A raster chart is a digital representation of an existing nautical chart. It retains the appearance and symbols of the original chart and can be used with compatible navigation or charting software.

A vector chart represents cartographic information as digital data. It allows greater interaction with the navigation system and forms the basis of ENCs, or Electronic Navigational Charts.

For a Pacific crossing, these different formats can complement each other depending on the stages of the voyage.

What Scale Should Be Used for a Pacific Ocean Nautical Chart?

Chart scale is an essential consideration when selecting a nautical chart.

A small-scale chart provides an overview of the Pacific and is used to plan a passage between several archipelagos or continents.

A medium-scale chart is suitable for regional route planning, for example between French Polynesia, the Cook Islands, Tonga, Fiji and New Caledonia.

A large-scale chart is required for coastal approaches, reef passes, channels, anchorages and harbours.

A complete chart portfolio may therefore combine:

• an ocean chart for the overall route;

• regional charts for the different stages;

• coastal charts;

• approach charts;

• harbour plans where necessary.

Planning a Pacific Crossing

A Pacific crossing may involve several thousand nautical miles and requires structured chart preparation.

A typical cruising route might connect the west coast of North America with Hawaii, then Hawaii with French Polynesia, before continuing towards the Cook Islands, Tonga, Fiji, Vanuatu, New Caledonia, Australia or New Zealand.

The ocean chart first provides an overview of the entire route. As the vessel approaches an archipelago, the navigator must move to larger-scale charts.

This progression from general chart to regional chart, coastal chart and approach chart is fundamental to long-distance navigation planning.

Conclusion

A Pacific Ocean nautical chart is an essential tool for understanding and planning navigation in the world's largest ocean. From the North Pacific to the South Pacific, from Japan to Australia, from the American coast to French Polynesia, the diversity of routes and environments requires charting adapted to each stage.

Shom, Admiralty, NGA, the Australian Hydrographic Office, the Canadian Hydrographic Service, LINZ and NOAA are among the important references depending on the geographical area concerned.

For a Pacific crossing, the objective is generally not to select a single chart, but to assemble a coherent set of charts at different scales. An ocean chart allows the general route to be planned, while regional, coastal and approach charts progressively take over near land, reefs, passages and ports.

FAQ – Pacific Ocean Nautical Charts

What is a Pacific Ocean nautical chart used for?

It is used to plan an ocean crossing, offshore passage, circumnavigation or coastal navigation in the different regions of the Pacific.

Which areas are covered by Pacific Ocean nautical charts?

Depending on the chart series, coverage may include the North and South Pacific, the American and Asian coasts, Japan, Australia, New Zealand, Polynesia, Melanesia and Micronesia, as well as numerous seas and archipelagos.

Who are the main publishers of Pacific nautical charts?

Major organisations include Shom, Admiralty/UKHO, NGA, the Australian Hydrographic Office, the Canadian Hydrographic Service, LINZ and NOAA, depending on the geographical area.

Which chart should be used for a Pacific crossing?

A small-scale ocean chart is used to plan the overall route. Regional and coastal charts are then required for the different stages and approaches to islands.

Which charts should be used for navigation in French Polynesia?

French Polynesia is covered by Shom charts covering the various archipelagos and islands, supplemented in some areas by other international charting authorities. Reef, pass and lagoon approaches require sufficiently detailed scales.

Are the Cook Islands, Tonga and Fiji covered by nautical charts?

Yes. Various international chart series cover these archipelagos. The appropriate chart depends on the exact route, geographical area and required scale.

Which chart should be used for navigation in New Caledonia?

New Caledonia requires charts suitable for coastal navigation and approaches to the many islands, passages and reefs of the archipelago. Shom and Admiralty are among the available references depending on the area.

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

An ocean chart covers a very large area at small scale and is primarily used to plan an offshore route. A coastal chart covers a smaller area with greater detail on depths, dangers and aids to navigation.

What is a Pacific Ocean ENC?

An ENC, or Electronic Navigational Chart, is an official vector electronic chart designed for use in a compatible navigation system, particularly an ECDIS meeting the applicable standards.

What scale should be used when navigating between Pacific islands?

For a passage between archipelagos, a regional or ocean chart may be suitable. For approaching an island, reef, passage or harbour, a larger-scale chart is required.

Why are several charts needed to cross the Pacific?

Because a single scale cannot simultaneously provide an overview of several thousand nautical miles and the level of detail required for precise navigation around coastlines, reefs, passages and ports.